Date: Wed, 14 Jan 2009 20:11:41 -0800
Reply-To: Walter Houle <whoule@ECSCONTROLS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Walter Houle <whoule@ECSCONTROLS.COM>
Subject: Re: Transmission Noise ?
In-Reply-To: <00a401c9768d$617ae4c0$6601a8c0@PROSPERITY>
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Sorry, the original thread got really long so I clipped off a lot of it.
Here's some quick answers. Scott's questions are in quotes:
"describe the noise and WHEN it does it" - It's a steady droning that occurs at 30 mph and over. Its as loud as the motor is between 30 to 45 mph.
"And how old or new is the transmission?" - It's the original one from 1985. 210,000 miles on it. No service was ever done on it except for infrequent oil changes. Now using Redline MT-90 for the last 3,000 miles.
"why are you sure it's in the rear, and not the front?" - It just sounds like it is. The shop also says its in the rear. We spun the front wheels in the air and they felt fine. Those bearings were just repacked, not replaced.
"type of noise..........whirring, rumbling, high pitched whine, etc?" - It's a steady drone, no rumbling. At speeds over 55 mph it resonates with the engine noise and goes wah wah wah.
"if you have not actually seen inside your CV joints" - I installed 4 new Lobros a week or so and 150 miles before the rear wheel bearings were replaced. I used a 90G grease tube from Van-Café in each, plus I shot some more in with a needle afterwards.
"WHEN did this noise start?" - On a 200 mile trip immediately after the bearings were installed.
"did it gradually develop, or did it start more suddenly?" - Gradually. I noticed the wah wah sound after the first 50 miles on the freeway and its gotten slightly louder over time.
"after what work or changes to the van?" - The new CVs were in for approx. 150 miles and they were always quiet. Then the front wheel bearings were repacked and new rears were installed. The noise started 50 miles after the bearing work.
"Does it make the noise coasting down the road, engine off, trans in neutral?" - Absolutely, In neutral, clutch in, clutch out, engine off, swerving side to side all have no effect on it.
I have a hard time suspecting the transmission or the CVs because it started right after the rear wheel bearings were installed but I can't be sure. Is it safe to do the listening stick test sitting on the back seat with the engine cover off and someone driving??
Thanks for your interest in this.
Walter
85 Vanagon
-----Original Message-----
From: Scott Daniel - Turbovans [mailto:scottdaniel@turbovans.com]
Sent: Wednesday, January 14, 2009 1:16 PM
To: Walter Houle; vanagon@GERRY.VANAGON.COM
Subject: Re: Transmission Noise ?
hi there,
sure, try some ordinary cheaper gear oil as a test. I don't see how that
could hurt.
It's been a while......... describe the noise and WHEN it does it, again,
please.
And how old or new is the transmission ?
and why are you sure it's in the rear, and not the front, this noise ?
also the type of noise..........whirring, rumbling, high pitched whine, etc.
on listening to rear wheel bearings.....'in the air' .
first I do it with the tires and wheels on,
then with those removed,
and finally with the rear drums removed.
also.....if you have not actually seen inside your CV joints.....all 4 of
them......
you really need to know that those are not dry, or excessively loose.
I've seen many, many dry CV joints.
Not saying I think that's where the issue is.........just that you need to
be sure that's where it is not.
oh yes........WHEN did this noise start ?
did it gradually develop, or did it start more suddenly, and if so, after
what work or changes to the van ?
Does it make the noise coasting down the road , engine off, trans in neutral
?
Answers to those questions would help us help you.
thanks, Scott
----- Original Message -----
From: "Walter Houle" <whoule@ecscontrols.com>
To: <vanagon@GERRY.VANAGON.COM>
Cc: "Scott Daniel - Turbovans" <scottdaniel@turbovans.com>
Sent: Tuesday, January 13, 2009 5:49 PM
Subject: RE: Transmission Noise ?
Here's the latest: I did the stethoscope trick last week using a
Louisville Slugger for an earpiece. It worked great, but I didn't hear
anything unusual. I heard what I thought were normal mechanical gear
meshing sounds. Maybe they sounded a tiny bit rough or gravelly but they
didn't get louder or worse with increasing axle rpm. They were
consistent on either side of the van, too. So, nothing conclusive.
Next I visited the shop that installed the new rear wheel bearings. They
were nice enough to tear both sides down and re-inspect everything. They
didn't find anything there either. The bearings looked fine, no scoring
or bluing, and the grease was very clean. So again, nothing conclusive.
However, the noise is still there. One thought is the bearings
themselves. They're SKF. Is there any reason to believe this brand runs
noisier than the original OEM ones? If so, we could try a different
brand of bearing, like FAG.
One other recommendation I heard is to temporarily swap out the Redline
MT90 with some heavy Valvoline stuff and to see if that damps out the
noise. If it does, then I can suspect a worn transmission. Is this a
safe test to do?
Thanks,
Walter
1985 Vanagon MT