I'm wondering if anyone can shed any light on this. I had to replace the passenger side muffler. Now when I gun it and leave off the gas I have a loud RAT TAT TAT. Same when the engine is under load or backing up the hill into our driveway. I've laid under the coach with my wife gunning it trying to find a leak or where it's coming from. No luck. Any ideas?Sent from my U.S.Cellular© Smartphone
Exhaust problem
- Thread starter 78gmcroyale
- Start date
Normally you should replace both with identical.
On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
> I'm wondering if anyone can shed any light on this. I had to replace the
> passenger side muffler. Now when I gun it and leave off the gas I have a
> loud RAT TAT TAT. Same when the engine is under load or backing up the
> hill into our driveway. I've laid under the coach with my wife gunning it
> trying to find a leak or where it's coming from. No luck. Any ideas?Sent
> from my U.S.Cellular© Smartphone
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
> I'm wondering if anyone can shed any light on this. I had to replace the
> passenger side muffler. Now when I gun it and leave off the gas I have a
> loud RAT TAT TAT. Same when the engine is under load or backing up the
> hill into our driveway. I've laid under the coach with my wife gunning it
> trying to find a leak or where it's coming from. No luck. Any ideas?Sent
> from my U.S.Cellular© Smartphone
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
You cannot duplicate by running the engine with out loading it.
Put in gear and with brake and block on , then you’ll hear it. Be careful.
> Normally you should replace both with identical.
>
>
> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
>
>> I'm wondering if anyone can shed any light on this. I had to replace the
>> passenger side muffler. Now when I gun it and leave off the gas I have a
>> loud RAT TAT TAT. Same when the engine is under load or backing up the
>> hill into our driveway. I've laid under the coach with my wife gunning it
>> trying to find a leak or where it's coming from. No luck. Any ideas?Sent
>> from my U.S.Cellular© Smartphone
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
Put in gear and with brake and block on , then you’ll hear it. Be careful.
> Normally you should replace both with identical.
>
>
> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
>
>> I'm wondering if anyone can shed any light on this. I had to replace the
>> passenger side muffler. Now when I gun it and leave off the gas I have a
>> loud RAT TAT TAT. Same when the engine is under load or backing up the
>> hill into our driveway. I've laid under the coach with my wife gunning it
>> trying to find a leak or where it's coming from. No luck. Any ideas?Sent
>> from my U.S.Cellular© Smartphone
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
> You cannot duplicate by running the engine with out loading it.
> Put in gear and with brake and block on , then you’ll hear it. Be careful.
>
>
>> Normally you should replace both with identical.
>> Could be also an clearance issue
>>
>> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
>>
>>> I'm wondering if anyone can shed any light on this. I had to replace
>>> the passenger side muffler. Now when I gun it and leave off the gas I have
>>> a loud RAT TAT TAT. Same when the engine is under load or backing up the
>>> hill into our driveway. I've laid under the coach with my wife gunning it
>>> trying to find a leak or where it's coming from. No luck. Any ideas?Sent
>>> from my U.S.Cellular© Smartphone
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> --
>> Jim Kanomata
>> Applied/GMC, Newark,CA
>> jimk
>> http://www.gmcrvparts.com
>> 1-800-752-7502
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
> Put in gear and with brake and block on , then you’ll hear it. Be careful.
>
>
>> Normally you should replace both with identical.
>> Could be also an clearance issue
>>
>> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
>>
>>> I'm wondering if anyone can shed any light on this. I had to replace
>>> the passenger side muffler. Now when I gun it and leave off the gas I have
>>> a loud RAT TAT TAT. Same when the engine is under load or backing up the
>>> hill into our driveway. I've laid under the coach with my wife gunning it
>>> trying to find a leak or where it's coming from. No luck. Any ideas?Sent
>>> from my U.S.Cellular© Smartphone
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> --
>> Jim Kanomata
>> Applied/GMC, Newark,CA
>> jimk
>> http://www.gmcrvparts.com
>> 1-800-752-7502
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
I am unsure at this point whether you are hearing a rattle from the exhaust
pipe or new muffler hitting the frame somewhere, or if the noise is coming
from the exhaust note itself. If the latter is the problem, Jim K is right.
Jim Hupy
Salem, Oregon
On Sat, Jun 6, 2020 at 3:47 PM Jim Kanomata via Gmclist <
> Normally you should replace both with identical.
>
>
> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
>
> > I'm wondering if anyone can shed any light on this. I had to replace the
> > passenger side muffler. Now when I gun it and leave off the gas I have a
> > loud RAT TAT TAT. Same when the engine is under load or backing up the
> > hill into our driveway. I've laid under the coach with my wife gunning
> it
> > trying to find a leak or where it's coming from. No luck. Any
> ideas?Sent
> > from my U.S.Cellular© Smartphone
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
pipe or new muffler hitting the frame somewhere, or if the noise is coming
from the exhaust note itself. If the latter is the problem, Jim K is right.
Jim Hupy
Salem, Oregon
On Sat, Jun 6, 2020 at 3:47 PM Jim Kanomata via Gmclist <
> Normally you should replace both with identical.
>
>
> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale via Gmclist <
>
> > I'm wondering if anyone can shed any light on this. I had to replace the
> > passenger side muffler. Now when I gun it and leave off the gas I have a
> > loud RAT TAT TAT. Same when the engine is under load or backing up the
> > hill into our driveway. I've laid under the coach with my wife gunning
> it
> > trying to find a leak or where it's coming from. No luck. Any
> ideas?Sent
> > from my U.S.Cellular© Smartphone
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.gmcrvparts.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
I've ordered a 2nd muffler to replace the drivers side too.=C2=A0 I may hav=
e gotten a bad muffler with a loose baffle.Sent from my U.S.Cellular=C2=
=A9 Smartphone -------- Original message --------From: James Hupy via Gmc=
list Date: 6/6/20 5:52 PM (GMT-06:00) To: gmcli=
st Cc: James Hupy Subject: Re: [GMCn=
et] Exhaust problem I am unsure at this point whether you are hearing a rat=
tle from the exhaustpipe or new muffler hitting the frame somewhere, or if =
the noise is comingfrom the exhaust note itself. If the latter is the probl=
em, Jim K is right.Jim HupySalem, OregonOn Sat, Jun 6, 2020 at 3:47 PM Jim =
Kanomata via Gmclist wrote:> Normally you should =
replace both with identical.>>> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale =
via Gmclist gmclist> wrote:>> > I'm wondering if anyone =
can shed any light on this.=C2=A0 I had to replace the> > passenger side mu=
ffler.=C2=A0 Now when I gun it and leave off the gas I have a> > loud RAT T=
AT TAT.=C2=A0 Same when the engine is under load or backing up the> > hill =
into our driveway.=C2=A0 I've laid under the coach with my wife gunning> it=
> > trying to find a leak or where it's coming from.=C2=A0 No luck.=C2=
=A0 Any> ideas?Sent> > from my=C2=A0 U.S.Cellular=C2=A9 Smartphone> > _____=
__________________________________________> > GMCnet mailing list> > Unsubs=
cribe or Change List Options:> > http://list.gmcnet.org/mailman/listinfo/gm=
clist_list.gmcnet.org> >> --> Jim Kanomata> Applied/GMC, Newark,CA> jimk=
pliedairfilters.com> http://www.gmcrvparts.com> 1-800-752-7502> ___________=
____________________________________> GMCnet mailing list> Unsubscribe or C=
hange List Options:> http://list.gmcnet.org/mailman/listinfo/gmclist_list.g=
mcnet.org>_______________________________________________GMCnet mailing lis=
tUnsubscribe or Change List Options:http://list.gmcnet.org/mailman/listinfo=
/gmclist_list.gmcnet.org
e gotten a bad muffler with a loose baffle.Sent from my U.S.Cellular=C2=
=A9 Smartphone -------- Original message --------From: James Hupy via Gmc=
list Date: 6/6/20 5:52 PM (GMT-06:00) To: gmcli=
st Cc: James Hupy Subject: Re: [GMCn=
et] Exhaust problem I am unsure at this point whether you are hearing a rat=
tle from the exhaustpipe or new muffler hitting the frame somewhere, or if =
the noise is comingfrom the exhaust note itself. If the latter is the probl=
em, Jim K is right.Jim HupySalem, OregonOn Sat, Jun 6, 2020 at 3:47 PM Jim =
Kanomata via Gmclist wrote:> Normally you should =
replace both with identical.>>> On Sat, Jun 6, 2020 at 3:27 PM 78gmcroyale =
via Gmclist gmclist> wrote:>> > I'm wondering if anyone =
can shed any light on this.=C2=A0 I had to replace the> > passenger side mu=
ffler.=C2=A0 Now when I gun it and leave off the gas I have a> > loud RAT T=
AT TAT.=C2=A0 Same when the engine is under load or backing up the> > hill =
into our driveway.=C2=A0 I've laid under the coach with my wife gunning> it=
> > trying to find a leak or where it's coming from.=C2=A0 No luck.=C2=
=A0 Any> ideas?Sent> > from my=C2=A0 U.S.Cellular=C2=A9 Smartphone> > _____=
__________________________________________> > GMCnet mailing list> > Unsubs=
cribe or Change List Options:> > http://list.gmcnet.org/mailman/listinfo/gm=
clist_list.gmcnet.org> >> --> Jim Kanomata> Applied/GMC, Newark,CA> jimk=
pliedairfilters.com> http://www.gmcrvparts.com> 1-800-752-7502> ___________=
____________________________________> GMCnet mailing list> Unsubscribe or C=
hange List Options:> http://list.gmcnet.org/mailman/listinfo/gmclist_list.g=
mcnet.org>_______________________________________________GMCnet mailing lis=
tUnsubscribe or Change List Options:http://list.gmcnet.org/mailman/listinfo=
/gmclist_list.gmcnet.org
What are you trying to tell me Jim?=C2=A0 I'm not clear on this.Sent from m=
y U.S.Cellular=C2=A9 Smartphone -------- Original message --------From: =
Jim Kanomata via Gmclist Date: 6/6/20 5:51 PM (=
GMT-06:00) To: gmclist Cc: Jim Kanomata Subject: Re: [GMCnet] Exhaust problem On Sat, Jun 6, 2020 at 3:49 PM J=
im Kanomata wrote:> You cannot duplicate by running=
the engine with out loading it.> Put in gear and with brake and block on ,=
then you=E2=80=99ll hear it. Be careful.>> On Sat, Jun 6, 2020 at 3:46 PM =
Jim Kanomata wrote:>>> Normally you should replace =
both with identical.>> Could be also an clearance issue>>>> On Sat, Jun 6, =
2020 at 3:27 PM 78gmcroyale via Gmclist > gmclist> wrote:=
>>>>> I'm wondering if anyone can shed any light on this.=C2=A0 I had to re=
place>>> the passenger side muffler.=C2=A0 Now when I gun it and leave off =
the gas I have>>> a loud RAT TAT TAT.=C2=A0 Same when the engine is under l=
oad or backing up the>>> hill into our driveway.=C2=A0 I've laid under the =
coach with my wife gunning it>>> trying to find a leak or where it's coming=
from.=C2=A0 No luck.=C2=A0 Any ideas?Sent>>> from my=C2=A0 U.S.Cellular=
=C2=A9 Smartphone>>> _______________________________________________>>> GMC=
net mailing list>>> Unsubscribe or Change List Options:>>> http://list.gmcn=
et.org/mailman/listinfo/gmclist_list.gmcnet.org>>>>> -->> Jim Kanomata>> Ap=
plied/GMC, Newark,CA>> jimk>> http://www.gmcrvparts.c=
om>> 1-800-752-7502>>> --> Jim Kanomata> Applied/GMC, Newark,CA> jimk=
edairfilters.com> http://www.gmcrvparts.com> 1-800-752-7502>-- Jim Kanomata=
Applied/GMC, Newark,CAjimk://www.gmcrvparts.com1-=
800-752-7502_______________________________________________GMCnet mailing l=
istUnsubscribe or Change List Options:http://list.gmcnet.org/mailman/listin=
fo/gmclist_list.gmcnet.org
y U.S.Cellular=C2=A9 Smartphone -------- Original message --------From: =
Jim Kanomata via Gmclist Date: 6/6/20 5:51 PM (=
GMT-06:00) To: gmclist Cc: Jim Kanomata Subject: Re: [GMCnet] Exhaust problem On Sat, Jun 6, 2020 at 3:49 PM J=
im Kanomata wrote:> You cannot duplicate by running=
the engine with out loading it.> Put in gear and with brake and block on ,=
then you=E2=80=99ll hear it. Be careful.>> On Sat, Jun 6, 2020 at 3:46 PM =
Jim Kanomata wrote:>>> Normally you should replace =
both with identical.>> Could be also an clearance issue>>>> On Sat, Jun 6, =
2020 at 3:27 PM 78gmcroyale via Gmclist > gmclist> wrote:=
>>>>> I'm wondering if anyone can shed any light on this.=C2=A0 I had to re=
place>>> the passenger side muffler.=C2=A0 Now when I gun it and leave off =
the gas I have>>> a loud RAT TAT TAT.=C2=A0 Same when the engine is under l=
oad or backing up the>>> hill into our driveway.=C2=A0 I've laid under the =
coach with my wife gunning it>>> trying to find a leak or where it's coming=
from.=C2=A0 No luck.=C2=A0 Any ideas?Sent>>> from my=C2=A0 U.S.Cellular=
=C2=A9 Smartphone>>> _______________________________________________>>> GMC=
net mailing list>>> Unsubscribe or Change List Options:>>> http://list.gmcn=
et.org/mailman/listinfo/gmclist_list.gmcnet.org>>>>> -->> Jim Kanomata>> Ap=
plied/GMC, Newark,CA>> jimk>> http://www.gmcrvparts.c=
om>> 1-800-752-7502>>> --> Jim Kanomata> Applied/GMC, Newark,CA> jimk=
edairfilters.com> http://www.gmcrvparts.com> 1-800-752-7502>-- Jim Kanomata=
Applied/GMC, Newark,CAjimk://www.gmcrvparts.com1-=
800-752-7502_______________________________________________GMCnet mailing l=
istUnsubscribe or Change List Options:http://list.gmcnet.org/mailman/listin=
fo/gmclist_list.gmcnet.org
Gunning the engine will not duplicate as there is dramatic difference in
amount of air consumed and Exaust flow.
On Sat, Jun 6, 2020 at 7:32 PM 78gmcroyale via Gmclist <
> What are you trying to tell me Jim? I'm not clear on this.Sent from my
> U.S.Cellular© Smartphone
> -------- Original message --------From: Jim Kanomata via Gmclist <
> gmclist> Date: 6/6/20 5:51 PM (GMT-06:00) To:
> gmclist Cc: Jim Kanomata Subject:
> Re: [GMCnet] Exhaust problem On Sat, Jun 6, 2020 at 3:49 PM Jim Kanomata <
> jimkanomata> wrote:> You cannot duplicate by running the engine
> with out loading it.> Put in gear and with brake and block on , then you’ll
> hear it. Be careful.>> On Sat, Jun 6, 2020 at 3:46 PM Jim Kanomata <
> jimkanomata> wrote:>>> Normally you should replace both with
> identical.>> Could be also an clearance issue>>>> On Sat, Jun 6, 2020 at
> 3:27 PM 78gmcroyale via Gmclist > gmclist> wrote:>>>>>
> I'm wondering if anyone can shed any light on this. I had to replace>>>
> the passenger side muffler. Now when I gun it and leave off the gas I
> have>>> a loud RAT TAT TAT. Same when the engine is under load or backing
> up the>>> hill into our driveway. I've laid under the coach with my wife
> gunning it>>> trying to find a leak or where it's coming from. No luck.
> Any ideas?Sent>>> from my U.S.Cellular© Smartphone>>>
> _______________________________________________>>> GMCnet mailing list>>>
> Unsubscribe or Change List Options:>>>
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org>>>>> -->>
> Jim Kanomata>> Applied/GMC, Newark,CA>> jimk>>
> http://www.gmcrvparts.com>> 1-800-752-7502>>> --> Jim Kanomata>
> Applied/GMC, Newark,CA> jimk>
> http://www.gmcrvparts.com> 1-800-752-7502>-- Jim KanomataApplied/GMC,
> Newark,CAjimk://www.gmcrvparts.com1-800-752-7502_______________________________________________GMCnet
> mailing listUnsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
amount of air consumed and Exaust flow.
On Sat, Jun 6, 2020 at 7:32 PM 78gmcroyale via Gmclist <
> What are you trying to tell me Jim? I'm not clear on this.Sent from my
> U.S.Cellular© Smartphone
> -------- Original message --------From: Jim Kanomata via Gmclist <
> gmclist> Date: 6/6/20 5:51 PM (GMT-06:00) To:
> gmclist Cc: Jim Kanomata Subject:
> Re: [GMCnet] Exhaust problem On Sat, Jun 6, 2020 at 3:49 PM Jim Kanomata <
> jimkanomata> wrote:> You cannot duplicate by running the engine
> with out loading it.> Put in gear and with brake and block on , then you’ll
> hear it. Be careful.>> On Sat, Jun 6, 2020 at 3:46 PM Jim Kanomata <
> jimkanomata> wrote:>>> Normally you should replace both with
> identical.>> Could be also an clearance issue>>>> On Sat, Jun 6, 2020 at
> 3:27 PM 78gmcroyale via Gmclist > gmclist> wrote:>>>>>
> I'm wondering if anyone can shed any light on this. I had to replace>>>
> the passenger side muffler. Now when I gun it and leave off the gas I
> have>>> a loud RAT TAT TAT. Same when the engine is under load or backing
> up the>>> hill into our driveway. I've laid under the coach with my wife
> gunning it>>> trying to find a leak or where it's coming from. No luck.
> Any ideas?Sent>>> from my U.S.Cellular© Smartphone>>>
> _______________________________________________>>> GMCnet mailing list>>>
> Unsubscribe or Change List Options:>>>
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org>>>>> -->>
> Jim Kanomata>> Applied/GMC, Newark,CA>> jimk>>
> http://www.gmcrvparts.com>> 1-800-752-7502>>> --> Jim Kanomata>
> Applied/GMC, Newark,CA> jimk>
> http://www.gmcrvparts.com> 1-800-752-7502>-- Jim KanomataApplied/GMC,
> Newark,CAjimk://www.gmcrvparts.com1-800-752-7502_______________________________________________GMCnet
> mailing listUnsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502
Maybe the outer shell of your new muffler can't handle the uneven 4 cylinder pulse and is popping in and out. BTDT with a new muff before, and had to
get customer to up the ante to a heavier duty brand. As far as loose insides go, I have even seen several of the heavily constructed Flowmasters come
back to the shop with loose insides in less than a year after installation. The short muffs we have on the GMCs are particularly prone to the outer
shell vibrating at certain rpms.
Run a compression check on that side to make sure you don't have a burned exhaust valve.
--
Terry Kelpien
ASE Master Technician
73 Glacier 260
Smithfield, Va.
get customer to up the ante to a heavier duty brand. As far as loose insides go, I have even seen several of the heavily constructed Flowmasters come
back to the shop with loose insides in less than a year after installation. The short muffs we have on the GMCs are particularly prone to the outer
shell vibrating at certain rpms.
Run a compression check on that side to make sure you don't have a burned exhaust valve.
--
Terry Kelpien
ASE Master Technician
73 Glacier 260
Smithfield, Va.
Engine is a new rebuild with only 2500 miles on it.Sent from my U.S.Cellul=
ar=C2=A9 Smartphone -------- Original message --------From: Terry via Gmc=
list Date: 6/6/20 10:24 PM (GMT-06:00) To: gmcl=
ist Cc: Terry Subject: Re: [GMCnet]=
Exhaust problem Maybe the outer shell of your new muffler can't handle the=
uneven 4 cylinder pulse and is popping in and out. BTDT with a new muff be=
fore, and had toget customer to up the ante to a heavier duty brand. As far=
as loose insides go, I have even seen several of the heavily constructed F=
lowmasters comeback to the shop with loose insides in less than a year afte=
r installation. The short muffs we have on the GMCs are particularly prone =
to the outershell vibrating at certain rpms.Run a compression check on that=
side to make sure you don't have a burned exhaust valve.-- Terry KelpienAS=
E Master Technician73 Glacier 260Smithfield, Va.___________________________=
____________________GMCnet mailing listUnsubscribe or Change List Options:h=
ttp://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
ar=C2=A9 Smartphone -------- Original message --------From: Terry via Gmc=
list Date: 6/6/20 10:24 PM (GMT-06:00) To: gmcl=
ist Cc: Terry Subject: Re: [GMCnet]=
Exhaust problem Maybe the outer shell of your new muffler can't handle the=
uneven 4 cylinder pulse and is popping in and out. BTDT with a new muff be=
fore, and had toget customer to up the ante to a heavier duty brand. As far=
as loose insides go, I have even seen several of the heavily constructed F=
lowmasters comeback to the shop with loose insides in less than a year afte=
r installation. The short muffs we have on the GMCs are particularly prone =
to the outershell vibrating at certain rpms.Run a compression check on that=
side to make sure you don't have a burned exhaust valve.-- Terry KelpienAS=
E Master Technician73 Glacier 260Smithfield, Va.___________________________=
____________________GMCnet mailing listUnsubscribe or Change List Options:h=
ttp://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can help....why did you change the muffler in the
first place? Did you replace the old one with exactly the same thing?
--
Rich Mondor,
Brockville, ON
77 Hughes 2600
first place? Did you replace the old one with exactly the same thing?
--
Rich Mondor,
Brockville, ON
77 Hughes 2600
And is the exhaust crossover in the intake manifold blocked?
> OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can help....why did you change the muffler in
> the first place? Did you replace the old one with exactly the same thing?
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
> OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can help....why did you change the muffler in
> the first place? Did you replace the old one with exactly the same thing?
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
I replaced it because it was bad. I replaced it with the identical one.Sent from my U.S.Cellular© Smartphone
-------- Original message --------From: 6cuda6--- via Gmclist Date: 6/7/20 7:31 PM (GMT-06:00) To: gmclist Cc: 6cuda6 Subject: Re: [GMCnet] Exhaust problem OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can help....why did you change the muffler in thefirst place? Did you replace the old one with exactly the same thing?-- Rich Mondor,Brockville, ON77 Hughes 2600_______________________________________________GMCnet mailing listUnsubscribe or Change List Options:http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
-------- Original message --------From: 6cuda6--- via Gmclist Date: 6/7/20 7:31 PM (GMT-06:00) To: gmclist Cc: 6cuda6 Subject: Re: [GMCnet] Exhaust problem OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can help....why did you change the muffler in thefirst place? Did you replace the old one with exactly the same thing?-- Rich Mondor,Brockville, ON77 Hughes 2600_______________________________________________GMCnet mailing listUnsubscribe or Change List Options:http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> Yes, I have the Dick Paterson intake block off installed.Sent from my U.S.Cellular© Smartphone
Well forget that idea. It is not a problem of the exhaust crossing over from one less restrictive side to the other or going back and forth.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Well forget that idea. It is not a problem of the exhaust crossing over from one less restrictive side to the other or going back and forth.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
So the first thing that comes to mind is the exhaust manifold to pipe donut....was it changed?
> I replaced it because it was bad. I replaced it with the identical one.Sent from my U.S.Cellular© Smartphone
> -------- Original message --------From: 6cuda6--- via Gmclist Date: 6/7/20 7:31 PM (GMT-06:00) To: gmclist Cc: 6cuda6
> Subject: Re: [GMCnet] Exhaust problem OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can
> help....why did you change the muffler in thefirst place? Did you replace the old one with exactly the same thing?-- Rich Mondor,Brockville, ON77
> Hughes 2600_______________________________________________GMCnet mailing listUnsubscribe or Change List
> Options:http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
--
Rich Mondor,
Brockville, ON
77 Hughes 2600
> I replaced it because it was bad. I replaced it with the identical one.Sent from my U.S.Cellular© Smartphone
> -------- Original message --------From: 6cuda6--- via Gmclist Date: 6/7/20 7:31 PM (GMT-06:00) To: gmclist Cc: 6cuda6
> Subject: Re: [GMCnet] Exhaust problem OK, i'm going to ask you a different question and maybe it will shed some light on this a bit so we can
> help....why did you change the muffler in thefirst place? Did you replace the old one with exactly the same thing?-- Rich Mondor,Brockville, ON77
> Hughes 2600_______________________________________________GMCnet mailing listUnsubscribe or Change List
> Options:http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> _______________________________________________
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--
Rich Mondor,
Brockville, ON
77 Hughes 2600
I will check donuts today.Sent from my U.S.Cellular=C2=A9 Smartphone ---=
----- Original message --------From: 6cuda6--- via Gmclist Date: 6/8/20 7:45 AM (GMT-06:00) To: gmclist Cc=
: 6cuda6 Subject: Re: [GMCnet] Exhaust problem So the first thing=
that comes to mind is the exhaust manifold to pipe donut....was it changed=
was bad.=C2=A0 I replaced it with the identical one.Sent from my=C2=A0 U.S.=
Cellular=C2=A9 Smartphone> -------- Original message --------From: 6cuda6--=
- via Gmclist=C2=A0 Date: 6/7/20=C2=A0 7:31 PM=C2=A0 (GMT-06:00) To: gmclis=
t Cc: 6cuda6> Subject: Re: [GMCnet] Exhaust probl=
em OK, i'm going to ask you a different question and maybe it will shed som=
e light on this a bit so we can> help....why did you change the muffler in =
thefirst place? Did you replace the old one with exactly the same thing?-- =
Rich Mondor,Brockville, ON77> Hughes 2600__________________________________=
_____________GMCnet mailing listUnsubscribe or Change List> Options:http://=
list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org> _________________=
______________________________> GMCnet mailing list> Unsubscribe or Change =
List Options:> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.=
org-- Rich Mondor,Brockville, ON77 Hughes 2600_____________________________=
__________________GMCnet mailing listUnsubscribe or Change List Options:htt=
p://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
----- Original message --------From: 6cuda6--- via Gmclist Date: 6/8/20 7:45 AM (GMT-06:00) To: gmclist Cc=
: 6cuda6 Subject: Re: [GMCnet] Exhaust problem So the first thing=
that comes to mind is the exhaust manifold to pipe donut....was it changed=
was bad.=C2=A0 I replaced it with the identical one.Sent from my=C2=A0 U.S.=
Cellular=C2=A9 Smartphone> -------- Original message --------From: 6cuda6--=
- via Gmclist=C2=A0 Date: 6/7/20=C2=A0 7:31 PM=C2=A0 (GMT-06:00) To: gmclis=
t Cc: 6cuda6> Subject: Re: [GMCnet] Exhaust probl=
em OK, i'm going to ask you a different question and maybe it will shed som=
e light on this a bit so we can> help....why did you change the muffler in =
thefirst place? Did you replace the old one with exactly the same thing?-- =
Rich Mondor,Brockville, ON77> Hughes 2600__________________________________=
_____________GMCnet mailing listUnsubscribe or Change List> Options:http://=
list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org> _________________=
______________________________> GMCnet mailing list> Unsubscribe or Change =
List Options:> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.=
org-- Rich Mondor,Brockville, ON77 Hughes 2600_____________________________=
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Ray,
I had moved my mufflers to a single rear back in 2005. A couple of years ago that original Flowmaster 70 series finally blew out, so I replaced it
with an identical Flowmaster that I got from Applied. While it should have been the same muffler, this new one sounded much different. When on the
throttle, it had a loud rap that I could hear especially when traveling in a tunnel, under bridges, and I could hear the rap echoing off of the street
curbs when traveling through towns. So, I added a resonator to the system. It is Vibrant 1142 3" Ultra Quiet Resonator and is available from Amazon.
Completely took the rap out. Now it has a little sound of a hot rod engine without the obnoxious rap.
http://www.gmcmhphotos.com/photos/rear-mounted-flowmaster/p34139-img-2885.html
So, while you think you replaced it with the same brand/model, over time these manufactures may have done some internal design changes that with your
engine would make it sound different. JMHO
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
I had moved my mufflers to a single rear back in 2005. A couple of years ago that original Flowmaster 70 series finally blew out, so I replaced it
with an identical Flowmaster that I got from Applied. While it should have been the same muffler, this new one sounded much different. When on the
throttle, it had a loud rap that I could hear especially when traveling in a tunnel, under bridges, and I could hear the rap echoing off of the street
curbs when traveling through towns. So, I added a resonator to the system. It is Vibrant 1142 3" Ultra Quiet Resonator and is available from Amazon.
Completely took the rap out. Now it has a little sound of a hot rod engine without the obnoxious rap.
http://www.gmcmhphotos.com/photos/rear-mounted-flowmaster/p34139-img-2885.html
So, while you think you replaced it with the same brand/model, over time these manufactures may have done some internal design changes that with your
engine would make it sound different. JMHO
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
> So, while you think you replaced it with the same brand/model, over
> time these manufactures may have done some internal design changes
> that with your engine would make it sound different. JMHO
I am not an exhaust guy, but I can imagine, that the sound of an exhaust
does change with age as well.
--
Best regards
Olly Schmidt
PGP KeyID: 0x4196BF22
'76a 26' Eleganza II - Virginia, US
'73 23' Sequoia - Schleswig-Holstein, Germany
> time these manufactures may have done some internal design changes
> that with your engine would make it sound different. JMHO
I am not an exhaust guy, but I can imagine, that the sound of an exhaust
does change with age as well.
--
Best regards
Olly Schmidt
PGP KeyID: 0x4196BF22
'76a 26' Eleganza II - Virginia, US
'73 23' Sequoia - Schleswig-Holstein, Germany
Interesting Larry, that's exactly how mine sounds.=C2=A0 I have a 2nd new o=
ne coming, after I put it on if I still have the sound I'll throw on a reso=
nater.=C2=A0 Thanks.=C2=A0 This is the kind of thing that drives me crazy=
=C2=A0I changed the remflex manifold gasket and the donut this morning alon=
g with one band clamp.=C2=A0 I'm about to take it for a test drive=C2=A0Ray=
Sent from my U.S.Cellular=C2=A9 Smartphone -------- Original message ---=
-----From: Larry via Gmclist Date: 6/8/20 8:39 A=
M (GMT-06:00) To: gmclist Cc: Larry Sub=
ject: Re: [GMCnet] Exhaust problem Ray,I had moved my mufflers to a single =
rear back in 2005. A couple of years ago that original Flowmaster 70 series=
finally blew out, so I replaced itwith an identical Flowmaster that I got =
from Applied. While it should have been the same muffler, this new one soun=
ded much different. When on thethrottle, it had a loud rap that I could hea=
r especially when traveling in a tunnel, under bridges, and I could hear th=
e rap echoing off of the streetcurbs when traveling through towns. So, I ad=
ded a resonator to the system. It is Vibrant 1142 3" Ultra Quiet Resonator =
and is available from Amazon.Completely took the rap out. Now it has a litt=
le sound of a hot rod engine without the obnoxious rap. http://www.gmcmhpho=
tos.com/photos/rear-mounted-flowmaster/p34139-img-2885.htmlSo, while you th=
ink you replaced it with the same brand/model, over time these manufactures=
may have done some internal design changes that with yourengine would make=
it sound different. JMHO-- Larry=C2=A0 78 Royale w/500 CaddyMenomonie, WI.=
_______________________________________________GMCnet mailing listUnsubscri=
be or Change List Options:http://list.gmcnet.org/mailman/listinfo/gmclist_l=
ist.gmcnet.org
ne coming, after I put it on if I still have the sound I'll throw on a reso=
nater.=C2=A0 Thanks.=C2=A0 This is the kind of thing that drives me crazy=
=C2=A0I changed the remflex manifold gasket and the donut this morning alon=
g with one band clamp.=C2=A0 I'm about to take it for a test drive=C2=A0Ray=
Sent from my U.S.Cellular=C2=A9 Smartphone -------- Original message ---=
-----From: Larry via Gmclist Date: 6/8/20 8:39 A=
M (GMT-06:00) To: gmclist Cc: Larry Sub=
ject: Re: [GMCnet] Exhaust problem Ray,I had moved my mufflers to a single =
rear back in 2005. A couple of years ago that original Flowmaster 70 series=
finally blew out, so I replaced itwith an identical Flowmaster that I got =
from Applied. While it should have been the same muffler, this new one soun=
ded much different. When on thethrottle, it had a loud rap that I could hea=
r especially when traveling in a tunnel, under bridges, and I could hear th=
e rap echoing off of the streetcurbs when traveling through towns. So, I ad=
ded a resonator to the system. It is Vibrant 1142 3" Ultra Quiet Resonator =
and is available from Amazon.Completely took the rap out. Now it has a litt=
le sound of a hot rod engine without the obnoxious rap. http://www.gmcmhpho=
tos.com/photos/rear-mounted-flowmaster/p34139-img-2885.htmlSo, while you th=
ink you replaced it with the same brand/model, over time these manufactures=
may have done some internal design changes that with yourengine would make=
it sound different. JMHO-- Larry=C2=A0 78 Royale w/500 CaddyMenomonie, WI.=
_______________________________________________GMCnet mailing listUnsubscri=
be or Change List Options:http://list.gmcnet.org/mailman/listinfo/gmclist_l=
ist.gmcnet.org
