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GMC whines [message #122127] Sun, 17 April 2011 14:01 Go to next message
shovelhead   United States
Messages: 30
Registered: January 2011
Karma: 0
Member
Hello. Good to see all the Patterson photos. Good to put faces to the names.
My coach (77 Palm Beach 403 53K miles) has begun to make a whining sound when under power. Take off and begin to notice it about 30 mph, increases slightly in pitch as speed increases, then is gone at ( or I just cant hear it any more) at cruising speed. Whining stops when I let off the throttle, then begins again when I give it gas. Also a slight whine when coming to a stop. Don't think it's bearings; have new ones and knuckles with zerks, which I maintain. My trans has a few minor leaks, the pan is clean, but don't know its service record. Fluid level is good. Had the coach about a year. Overall, coach is in good shape and well maintained,
Any ideas or links to study would be appreciated.

Thanks.
Roger
Re: [GMCnet] GMC whines [message #122129 is a reply to message #122127] Sun, 17 April 2011 14:07 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
It could be the bearing in the final drive.
Noise subsides when you let of on the throttle.

On Sun, Apr 17, 2011 at 12:01 PM, Roger Hartman <rdhhd1984@yahoo.com> wrote:
>
>
> Hello.  Good to see all the Patterson photos.  Good to put faces to the names.
> My coach (77 Palm Beach 403 53K miles) has begun to make a whining sound when under power.  Take off and begin to notice it about 30 mph, increases slightly in pitch as speed increases, then is gone at ( or I just cant hear it any more) at cruising speed.  Whining stops when I let off the throttle, then begins again when I give it gas.  Also a slight whine when coming to a stop.  Don't think it's bearings; have new ones and knuckles with zerks, which I maintain.  My trans has a few minor leaks, the pan is clean, but don't know its service record. Fluid level is good. Had the coach about a year. Overall, coach is in good shape and well maintained,
> Any ideas or links to study would be appreciated.
>
> Thanks.
> Roger
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] GMC whines [message #122130 is a reply to message #122129] Sun, 17 April 2011 14:29 Go to previous messageGo to next message
shovelhead   United States
Messages: 30
Registered: January 2011
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Member
Thanks, Jim. I had an idea that might be it. I was planning to get one of your 3:55 final drives one day . How long do you think before this becomes critical?

Thanks
Roger
Re: [GMCnet] GMC whines [message #122131 is a reply to message #122129] Sun, 17 April 2011 14:19 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
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Senior Member
I agree with Jim K. It sounds like a pinion bearing in the final drive. When
the noise slackens on decelleration, it is usually what it is. Keep a ear
tuned to the noise, if it is a "smooth" whine and it does not appear to be
getting worse, drive it until it gets worse. If however, it is a "rough
sounding" whine, better fix it soon. If you don't have lower differential
gears yet, now is the perfect time to install them and a limited slip diff
is also available. Easier to switch out the whole final drive as an exchange
assembly. If you wait for it to self destruct, it will have no core value as
it will not be able to be rebuilt.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Sun, Apr 17, 2011 at 12:07 PM, Jim Kanomata <jimkanomata@gmail.com>wrote:

> It could be the bearing in the final drive.
> Noise subsides when you let of on the throttle.
>
> On Sun, Apr 17, 2011 at 12:01 PM, Roger Hartman <rdhhd1984@yahoo.com>
> wrote:
> >
> >
> > Hello. Good to see all the Patterson photos. Good to put faces to the
> names.
> > My coach (77 Palm Beach 403 53K miles) has begun to make a whining sound
> when under power. Take off and begin to notice it about 30 mph, increases
> slightly in pitch as speed increases, then is gone at ( or I just cant hear
> it any more) at cruising speed. Whining stops when I let off the throttle,
> then begins again when I give it gas. Also a slight whine when coming to a
> stop. Don't think it's bearings; have new ones and knuckles with zerks,
> which I maintain. My trans has a few minor leaks, the pan is clean, but
> don't know its service record. Fluid level is good. Had the coach about a
> year. Overall, coach is in good shape and well maintained,
> > Any ideas or links to study would be appreciated.
> >
> > Thanks.
> > Roger
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] GMC whines [message #122133 is a reply to message #122130] Sun, 17 April 2011 14:43 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
When bearing get bad, it can go that way for thousand or hundred.
As the pinion bearing goes, the angle changes and then it can cause
the transmission to be effected along with the pinion and ring gear
breaking off.

On Sun, Apr 17, 2011 at 12:29 PM, Roger Hartman <rdhhd1984@yahoo.com> wrote:
>
>
> Thanks, Jim. I had an idea that might be it.  I was planning to get one of your 3:55 final drives one day .  How long do you think before this becomes critical?
>
> Thanks
> Roger
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] GMC whines [message #122134 is a reply to message #122130] Sun, 17 April 2011 14:41 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Minimally, you should have a blackstone analysis done of your final drive
lubricant. If there is hard surfaced metal particles beyond what is known to
be acceptable threshold limits, then this would tell you how significant the
damage is. It won't heal itself obviously, but I have personally heard faint
smooth whines go for many thousands of miles. How far you venture from home
base, whether you are a belt and suspenders kind of guy, how adept you are
with tools, will all figure into how soon it should be changed out. It is
kinda like cardiac arrythmias, some go on for years, some kill you the
second time you notice them. Life itself is a gamble and meant to be enjoyed
today as "Tomorrow is a promise to no one", in my opinion.
Jim Hupy
Salem, Or
78 GMC Royale 403

On Sun, Apr 17, 2011 at 12:29 PM, Roger Hartman <rdhhd1984@yahoo.com> wrote:

>
>
> Thanks, Jim. I had an idea that might be it. I was planning to get one of
> your 3:55 final drives one day . How long do you think before this becomes
> critical?
>
> Thanks
> Roger
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] GMC whines [message #122135 is a reply to message #122134] Sun, 17 April 2011 15:06 Go to previous messageGo to next message
shovelhead   United States
Messages: 30
Registered: January 2011
Karma: 0
Member
Thanks. I was planning to have my trans and drive looked at soon by a local shop, at least to address the leaks. Probably just as well to pick up a 3:55 and have them put it in as well. I can do a lot, but draw the line with transmission work. Dont want any trouble, since these coaches are hard to get off the side of the road.

Thanks again for your help.

Roger
Re: [GMCnet] GMC whines [message #122174 is a reply to message #122135] Sun, 17 April 2011 23:38 Go to previous messageGo to next message
hasbeen is currently offline  hasbeen   United States
Messages: 66
Registered: August 2005
Location: Cave Creek, AZ
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Member
Roger, I wouldn't condemn the final drive until after you have the trans checked out. Have them change the filter when they are in there as if it is getting clogged you will get a noise from the pump trying to suck up the fluid. The other thing that will make a similar noise is the power steering pump. A good auto tech should be able to pinpoint your problem. Good luck with it, Jim
Re: GMC whines [message #122177 is a reply to message #122127] Mon, 18 April 2011 00:23 Go to previous messageGo to next message
Luvn737s is currently offline  Luvn737s   United States
Messages: 1106
Registered: June 2007
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Senior Member
Put it in Neutral (carefully) while it is in motion (relatively slowly) and see it if the sound is tranny related or engine related. I agree with the power steering pump.

Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ

[Updated on: Mon, 18 April 2011 00:24]

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Re: [GMCnet] GMC whines [message #122184 is a reply to message #122127] Mon, 18 April 2011 06:51 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
Messages: 3447
Registered: May 2006
Karma: 0
Senior Member
Sounds like a final drive problem.

On Sun, Apr 17, 2011 at 12:01 PM, Roger Hartman <rdhhd1984@yahoo.com> wrote:

>
>
> Hello. Good to see all the Patterson photos. Good to put faces to the
> names.
> My coach (77 Palm Beach 403 53K miles) has begun to make a whining sound
> when under power. Take off and begin to notice it about 30 mph, increases
> slightly in pitch as speed increases, then is gone at ( or I just cant hear
> it any more) at cruising speed. Whining stops when I let off the throttle,
> then begins again when I give it gas. Also a slight whine when coming to a
> stop. Don't think it's bearings; have new ones and knuckles with zerks,
> which I maintain. My trans has a few minor leaks, the pan is clean, but
> don't know its service record. Fluid level is good. Had the coach about a
> year. Overall, coach is in good shape and well maintained,
> Any ideas or links to study would be appreciated.
>
> Thanks.
> Roger
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
Sierra Vista, AZ
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Re: GMC whines [message #122223 is a reply to message #122127] Mon, 18 April 2011 11:36 Go to previous message
gordh1   Canada
Messages: 332
Registered: February 2011
Karma: 0
Senior Member
shovelhead wrote on Sun, 17 April 2011 15:01

...begun to make a whining sound when under power. Take off and begin to notice it about 30 mph, increases slightly in pitch as speed increases, then is gone at ( or I just cant hear it any more) at cruising speed. Whining stops when I let off the throttle, then begins again when I give it gas. Also a slight whine when coming to a stop.


Laughing I have had a similar problem in many vehicles prior - usually the whine originated on or about the passenger seat. Though I had it solved by relabeling the radio volume 'up' to 'reduce whine' but that made it worse, so I changed the first radio preset button label to 'divorce'. Laughing
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