In cautionary stop mode... tracking a noise

hdavis

New member
Mar 13, 1998
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Heinz,

Check your lugs nuts! I tmay not be the cause of your problems, but I've
seen it on several vehicles in the past. Even though the wheels are hub
centered, if the nuts aren't tightened properly you can get wheel shimmy
that presents itself as you described.

>Hi folks... didn't get much further... yet :-)
>
>I'm getting a weird noise from the front and can feel it with my feet
oaccasionally.
>
>At this point it could be something simply vibrating or bearings ? (hope
not).
>
>i checked temps around both fron wheels and in behind, i.e. hub area as
soon as I pulled into the rest area just south of Everett, WA and found no
real diff from side to side. (used the laser thermometer, not just by touch).
>
>Since i did a fair bit of plumbing, timing chain, water pump, alternator
bracket change, added the Steering Absorber (Clasco) back in it could be
something just out of whack.
>
>The troubling part is that sometimes the noise/vibration increases when in
a turn. When I say vibration, it's ever so slight. Perhaps a caliper stuck
but then I should've seen a temp difference between left and right when I
measured the disc surface temp, I would think.
>
>One item of concern is the drive line assembly, i.e. cv joints. I don't
have any boots leaking but I've never looked at them. i assume they were
looked at when the engine was done, but that was quite a while ago (100+k).
>
>It seems to also manifest itself when brakes are applied, but not all the
time.
>
>As I mentioned, the big concern is CV joints type of stuff. Again, I'm
surmising that temp on a side with bad bearing would've been sufficiently
warmer so that I'd been able to tell a difference.
>
>I'm open to all suggestions, however grim :-)
>I'm tucked in for the night. Of course it's raining. I'll probably jack
the front up at first light to see what I can wiggle.
>
>In the meantime, in addition to advice I'm also open to shop/mechanic
recommendations as close to Everett as possible of course. One alternative
is to try and limp back home but I'd much rather carry on southbound ;-)
>
>Thanks in advance
>
>Heinz
>...another GMC adventure in the making.
>
Henry Davis Consulting, Inc / new product consulting
PO Box 1270 / product readiness reviews
Soquel, Ca 95073 / IP reviews
ph: (831) 462-5199 / full service marketing
fax: (831) 462-5198
http://www.henry-davis.com/ http://www.henry-davis.com
 
Heinz lets kill the myths.

1. CV joints. They seldom fail suddenly, unless you neglect them entirely.
Easy to check. Get in a parking lot and turn the coach in the sharpest turn
it will go in, first one direction and than the other. Turn off everything
inside of the coach so you can hear. If a CV joint is starting to go bad or
is bad it will click. More it clicks the worse it is. Replace it very soon
if it clicks. The clicking is the sound of the balls interfering with the
race in the joint. It may in soe cases by caused by a dry CV joint that just
needs to be repacked with grease. You can't tell until you take it apart
and visually inspect it.

2. Wheel bearings can be checked at the same time. sometimes when turning
in the circle you can hear the bearings rumble or grind. The wheel to the
outside of the circle always has the most force on it and will normally
sound off than if bad. Normally when running dry they will get hot and you
can feel the transfer of heat to the wheel.

3. I would check the inner CV joint cap screws to see if any of them have
came lose.

Stop worrying if these check out and have fun

>Hi folks... didn't get much further... yet :-)
>
>I'm getting a weird noise from the front and can feel it with my feet
oaccasionally.
>
>At this point it could be something simply vibrating or bearings ? (hope not).
>
>i checked temps around both fron wheels and in behind, i.e. hub area as
soon as I pulled into the rest area just south of Everett, WA and found no
real diff from side to side. (used the laser thermometer, not just by touch).
>
>Since i did a fair bit of plumbing, timing chain, water pump, alternator
bracket change, added the Steering Absorber (Clasco) back in it could be
something just out of whack.
>
>The troubling part is that sometimes the noise/vibration increases when in
a turn. When I say vibration, it's ever so slight. Perhaps a caliper stuck
but then I should've seen a temp difference between left and right when I
measured the disc surface temp, I would think.
>
>One item of concern is the drive line assembly, i.e. cv joints. I don't
have any boots leaking but I've never looked at them. i assume they were
looked at when the engine was done, but that was quite a while ago (100+k).
>
>It seems to also manifest itself when brakes are applied, but not all the time.
>
>As I mentioned, the big concern is CV joints type of stuff. Again, I'm
surmising that temp on a side with bad bearing would've been sufficiently
warmer so that I'd been able to tell a difference.
>
>I'm open to all suggestions, however grim :-)
>I'm tucked in for the night. Of course it's raining. I'll probably jack the
front up at first light to see what I can wiggle.
>
>In the meantime, in addition to advice I'm also open to shop/mechanic
recommendations as close to Everett as possible of course. One alternative
is to try and limp back home but I'd much rather carry on southbound ;-)
>
>Thanks in advance
>
>Heinz
>...another GMC adventure in the making.
>
>
>
>
>
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
"The beautiful Mohawk Vally"
 
>
> No shimmy, matter if fact it is driving dangerously
> nice and with less vibration than pre-timing chain.
> (Vibration according to mirrors)
>
> Looked underneath, all appears good.
> jacked up each front wheel for the crowbar/lift
> test... no slop or noise.
>
> changed MC, am just about to try and do a 1 person
> bleed, maybe. Gonna ask for some suggestions in
> another msg.

This seems too simple and obvious, but I'll toss it out there anyway...
How about a warped rotor? When I did my disc conversion, I noticed one
of the rotors didn't track true. Turned out there was a flake of rust
between the rotor and the hub. It would give you a pulsing that you
would feel with you foot.

Patrick
 
>
> Lets not disregard the obvious :-)
>
> Was there noise associated with it, other than rubbing sound?
>
> Sems I don't have the noise when first starting out but
> during heavy downhill breaking I could make it appear when
> heavy brake used.... but not all the time.

I caught it before driving the coach. The misalignment was visible
turning the hub. My Cherokee had warped rotors when I bought it(tire
gorillas with air tools) - no noise, but lots of shudder under heavy
braking.

Hmm, wonder if it could be the interaction of the new steering damper
and a warped front rotor? The damper might be making the noise as it
fights the vibration(really getting out in left field now).

Patrick
- --
Patrick Flowers
Mailto:patrick

The GMC Motorhome Page
http://www.gmcmotorhome.com
 
The CV joints are about the largest and studiest that you could find. I
have never seen one fail due to any other reason than not being properly
serviced and out of grease. In that case they always click to denote the
wear between the balls and race. I would be interested in knowing if anyone
has ever had a failure other than this. Even ones that really click and make
lots of noise in turns are for the most part silent when going straight
ahead as there is little stress on them in this mode. I would be 99.99% sure
that it is not the CV joint

>Thanks for the input Rick. Any and all suggestions appreciated.
>
>I'm still hoping that it's not the CV joint as that doesn't appear to be a
nice roadside project.
>
>I'm sure you're right re the "looked at at engine overhaul", I'm sure it's
like you suspect.
>
>heinz
>
>
>
>----Original Message-----
> >From: RickStapls
> >To: gmcmotorhome
> >Subject: Re: GMC: In cautionary stop mode... tracking a noise
> >Reply-To: gmcmotorhome
> >Date: Tuesday, June 22, 1999 8:28 PM
> >

> >
> >> The troubling part is that sometimes the noise/vibration increases
when in
> >a
> >> turn. When I say vibration, it's ever so slight. Perhaps a caliper stuck
> >but
> >> then I should've seen a temp difference between left and right when I
> >> measured the disc surface temp, I would think.
> >>
> >> One item of concern is the drive line assembly, i.e. cv joints. I don't
> >have
> >> any boots leaking but I've never looked at them. i assume they were
looked
> >at
> >> when the engine was done, but that was quite a while ago (100+k).
> >>
> >> It seems to also manifest itself when brakes are applied, but not
all the
> >> time.
> >>
> >Heinz,
> > Awfully hard to diagnose something like this at a distance, but I'll
throw
> >out some thoughts:
> >
> >1. My gut reaction says it's a CV joint. Most of the signs (subtle
> >vibration, increases in turns, etc.) point that way.
> >
> >2. I would assume they were NOT looked at when the engine was done.
No real
> >reason to, and engine mechanics don't get paid to overhaul the
driveline. If
> >there was no obvious fault, you can bet the axles came out, and the axles
> >went in.
> >
> >3. To check further, try your high-tech thermometer and see if there's
any
> >difference between left and right CV joints. (Inners and outers are
expected
> >to differ.) Even if nothing shows up there, I'd pull back the CV boot
on the
> >side you suspect. The outer joint grease should be gooey and dark, not
too
> >runny (Inners may be runny) and not at all dried out. If any joint seems
> >dried out, or shows signs of water or rust, pull the axle, tear down,
clean,
> >inspect races (the curved ball tracks), repack.
> >
> >Again, this is just a SWAG (Scientific Wild-Assed Guess; a guess based
upon
> >partial data), and anything's possible. Good luck, HTH
> >
> >Rick Staples
> >'75 Eleganza
> >Louisville, CO
> >
> >
> >
> >
>
>
>
 
Heinz:

Although you didn't specify, but if you're looking for original type front
wheel parts, info from the GMCMI Parts Interchange Index are pads:
Performance Friction (PF) 0524, caliper LH: NAPA 42-2010, RH: NAPA 42-2011,
rotor: GMC 701603. Brake rotor from mid 70s Toronado will work provided
three new holes are drilled in the face.

Info for the 80 mm size calipers (AutoZone numbers), pads (PF): 1543,
caliper LH 90185, RH 90184. These pads are the larger than the 0524 above
ones.

Paul Bartz

From: heinz [mailto:heinz]
Sent: Wednesday, June 23, 1999 12:39 AM
Subject: Re: GMC: In cautionary stop mode... tracking a noise

Could someone be kind enough to send me or post some generic numbers for
pads (the 'good' kind) and also calipers and rotors and perhaps a source
(NAPA?) Hopefully I'll hit (it's only a saying) Portland in the AM and I'll
dig up a NAPA or similar either there or Salem
 
Heinz...

How hard would it be to remove that steering damper that you just put
back on (before you go switching rotors ) Just a thought... I'm not
betting on that as a solution, but if it is relatively easy to remove or
just disconect the end that moves, and tie it up... just to rule that
out.

- --
"I do whatever my Rice Krispies tell me to..."
John said, err "Frosty the Snowman" said, from inside a 1974 Glacier.
 
>CV joints have never been looked at...

Something you may want to try if you have CV joint trouble while on the road:

Get a small grease gun, fill it with CV joint grease and use a needle to
shoot it into the boot. That should keep things lubed enough to get you
home without inflicting as much damage to the CV joint.

I had an old new-yorker and did this for 10,000 miles, injecting more
grease each time I change the oil. I was expecting to junk the car but
finally decided to keep it after all. The joint never did break. I just
ended up replacing it after 10,000 miles with a torn boot. Its still on the
road with 175K+ miles...

Dave
73 Sequoia
 
Heinz,

Just a thought that might get you by for awhile and back to home base if it
is your CV joints.

I have a hypodermic needle attached to a grease fitting.

Been awhile but I think I bought them at the NAPA store.

Plugs into grease gun to add grease to sealed bearings, add grease into
boots, etc.

Don Miller
Shenandoah Valley of Virginia