Transmission ??

J

johnny

New member
May 10, 2011
8,287
9
3
You may be leaking fluid around the trans dipstick if it isn't well sealed. Or from any of a number of other places. Best chance is wipe it clean,
run around a bit, and see what's damp.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
> This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this
> normal? Is there an easy fix? Should I be worried
> Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what
> the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I
> am actually going 62
>
> Thanks for any and all input

If you have a tach you can use this table to figure out which final drive you have.
http://www.appliedgmc.com/level.itml/icOid/482

--
Tom Lins
Elkton, FL
77 GM Rear Twin
 
Easiest way to check FD ratio would be driving a set speed, using the GPS, and check engine rpm with a tach. RPMs will give you an accurate idea of
your final drive ratio. Record and report engine rpm at GPS speeds of 60, 65, and 70 mph. Smarter guys than me will give you an idea of your final
drive ratio.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
Don't forget to consider tire size in your quest. Could also be that your chain drive has aftermarket gears. If your drive ratio is 3.21 the cover
will only have eight bolts. All others have 10.

--
1977 26 foot 403
 
> This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this
> normal? Is there an easy fix? Should I be worried
> Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what
> the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I
> am actually going 62
>
> Thanks for any and all input

Kevin,

Small leaks are not at all uncommon.

But:
3.55/3.07 = 1.156*55 = 63.6
An indicated 55 could easily be that far off.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Can the speedometer error be due to the wrong plastic gear installed in speedometer output housing on transmission?
I suppose one can pull it out, count the number of teeth, and compare it to the RPM vs. speed ratio to make sure it is correct one for the final drive
combination.

> This is from a limited mechanical member. The transmission leaks out a little fluid after sitting for a few weeks abd after a road trip. Is this
> normal? Is there an easy fix? Should I be worried
> Also my speedometer reads 7 MPH slower than what I am going, I checked this out with gps and having another vehicle next to me, do not know what
> the PO has put in for final drive. Is there something I can check to see what the final drive is? Fixes to this problem? So when I am driving 55 I
> am actually going 62
>
> Thanks for any and all input

--
Vadim Jitkov
'76 Glenbrook 26'
Pullman, WA
 
You should contact us as we are the major supplier of final drives and can
assist you better. You do not need to purchase anything from us.

On Thu, Dec 21, 2017 at 2:49 PM, Vadim Jitkov
wrote:

> Can the speedometer error be due to the wrong plastic gear installed in
> speedometer output housing on transmission?
> I suppose one can pull it out, count the number of teeth, and compare it
> to the RPM vs. speed ratio to make sure it is correct one for the final
> drive
> combination.
>
>

> > This is from a limited mechanical member. The transmission leaks out a
> little fluid after sitting for a few weeks abd after a road trip. Is this
> > normal? Is there an easy fix? Should I be worried
> > Also my speedometer reads 7 MPH slower than what I am going, I checked
> this out with gps and having another vehicle next to me, do not know what
> > the PO has put in for final drive. Is there something I can check to see
> what the final drive is? Fixes to this problem? So when I am driving 55 I
> > am actually going 62
> >
> > Thanks for any and all input
>
>
> --
> Vadim Jitkov
> '76 Glenbrook 26'
> Pullman, WA
>
> _______________________________________________
> 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.appliedgmc.com
1-800-752-7502
 
Things to check for the leak....
1. Dipstick O-Ring
2. Pan gasket
3. Pan gasket bolts (put a small o-ring around each.
4. Shift lever O-Ring
5. Downshift wire connection O-Ring
6. Vac modulator O-Ring

--
Ray Erspamer
78 GMC Royale
414-484-9431
 
Add to check transmission cooler lines where they attach to the top of the transmission. Use a flashlight. A leak there often runs down the front of the transmission and appears to be a pan gasket leak.

Emery Stora

>
> Things to check for the leak....
> 1. Dipstick O-Ring
> 2. Pan gasket
> 3. Pan gasket bolts (put a small o-ring around each.
> 4. Shift lever O-Ring
> 5. Downshift wire connection O-Ring
> 6. Vac modulator O-Ring
>
>
> --
> Ray Erspamer
> 78 GMC Royale
> 414-484-9431
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
I too have speedometer issues but decided not to do much. My transmission leak mystified me also but found weep hole in the final drive leaking and
the great Bob Dunohugh suggested leak in the seal between the transmission and final drive. Hello Bob, I think I finally got on this site, and tried
to call you this morning. Merry Xmas everyone!
 
Fluid leaks down from the torque convertor which raises the fluid level in the transmission pan over time. Could be you have a leak that is just
higher than the normal fluid level. Once the torque convertor leaks down some, you get your leak.
--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
Hubler 1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
yes, and yes. What you need to do is after the coach sits long enough to show a spot, >then< wipe the transmission clean and see where it's oozing.
Pan, dipstick, modulator and lines are the possibilities, with the first two being the most common. Since it's lower, the pan leaks, if any, will
appear before the fluid rises enough to get to the dipstick tube or modulator opening. The problem is to get the pan dry and then inspect daily while
the coach is level. Do this with an inspection mirror with a long holder, >do not< crawl under an unsupported coach. If you lose a suspension
component while you're under an unblocked coach, you will probably die.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
> I too have speedometer issues but decided not to do much. My transmission leak mystified me also but found weep hole in the final drive leaking
> and the great Bob Dunohugh suggested leak in the seal between the transmission and final drive. Hello Bob, I think I finally got on this site, and
> tried to call you this morning. Merry Xmas everyone!

Fipp,

Welcome to the group/family/cult/asylum...

Glad you found your way here.

Before you and we go too far, please build a sigfile. The regulars here have them and it is not coincidence. You can do this at and scroll down. Please put in a real name. We use those here so that when other owners from here meet you (and you will
meet) they may have some idea who you are. You should include an short about the coach because there are differences and some matter a whole lot.
And lastly, but not leastly is a sort of location. The half of this group that gets this as e-mail will never see the "Aledo, Illinois" in the
header. This matters because other that may choose to lend assistance need to know if you are in striking range, and there are environmental issues
that can be more easily cleared.

If you need assistance with the coach, you have come to the right place. But that is just the beginning. I do not know how long you have had the
coach, but you will soon discover that connecting to this group makes you a part of a community that is helping and supportive to a level that
astonishes many. This just one of the reasons that owners are so friendly. When you read here, you will hear of levels of assistance that most think
are outlandish, but we have come to love. This solid community so reminds me of that of the watermen that are my world that I have taken to welcoming
new people here much any new owner or vessel is welcomed there. So,

May the Good Lord bless this coach and all those that set forth within her.

Welcome "Fipp"

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
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