Transmission question, 901 related |
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Transmission question, 901 related |
MartyYeoman |
Oct 5 2006, 01:33 PM
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#1
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Senior Member Group: Members Posts: 1,520 Joined: 19-June 03 From: San Ramon, CA Member No.: 839 Region Association: Northern California |
I have started to notice noises that I attribute to excesive differential clearance.
When shifting up I can generate a "clunk" type sound. Also while driving I can generate the same thing by feathering the throttle. I can eliminate the noise by being excessivly smooth on acceleration. I seem to be able to duplicate the sound by raising the rear wheels off the ground and rotating the rear tire. My questions are: How is the pinnion/ring gear clearance set? Can it be adjusted with the dirve train still in the car? How long can I let this go? |
Joe Ricard |
Oct 5 2006, 01:50 PM
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#2
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Sure it's not the CV's ?
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Matt Romanowski |
Oct 5 2006, 01:50 PM
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#3
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Senior Member Group: Members Posts: 878 Joined: 4-January 04 From: Manchester, NH Member No.: 1,507 |
Are you sure it's the pinion / ring clearance? In my experience, when they start to wear bad, they usually resolve themselves rather quickly.
It could be the cv joints or the spiders. |
Joe Ricard |
Oct 5 2006, 01:52 PM
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#4
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Pinions get shims for depth and also via paper gaskets between intermediate plate and case.
Guys like Dr. Evil can hi-lite where I am wrong. He does lots of these transmissions. I have only fumbled through one so far. |
MartyYeoman |
Oct 5 2006, 06:09 PM
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#5
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Senior Member Group: Members Posts: 1,520 Joined: 19-June 03 From: San Ramon, CA Member No.: 839 Region Association: Northern California |
Any quick tests for CV diagnosis????????????
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r_towle |
Oct 5 2006, 06:44 PM
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#6
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Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
in this order
Front and rear engine mounts. If newer type with a side shifter you need to make sure the front mounts on the outer part of the bar, where the bar attaches to the body are nice and tight. The front inner ones are rubber with a bolt glued inside and are not repairable, just replacable. I am guessing that might be the issue. Aslo look at the rear mounts from tranny to body, but these are pretty solid The clunk could be from the engine rising up on one side due to the amazing amount ot torque that these little monsters produce...seriously it will make that sound. Easiest check, have someone do it while you watch from outside, and look into the engine bay...if the motor moves when the engage the clutch...its the mounts. CV joints will click while going forward or backwards just a little bit, again easier to hear from outside the car. Rich |
Dr Evil |
Oct 5 2006, 10:13 PM
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#7
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Send me your transmission! Group: Members Posts: 23,002 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
(IMG:style_emoticons/default/agree.gif)
Joe, you are right as well (thanks for the honorable mention (IMG:style_emoticons/default/wink.gif) ). To check CVs you can jack up one side at a time and rotate the up wheel for and aft. You should not hear or feel a click after some motion (clear?). I REALY doubt your ring and pinion are that far gone (IMG:style_emoticons/default/biggrin.gif) If so you would be in a worse shape. However, if the roller bearing on the pinion shaft goes, you can have some symptoms of the clearance changing. But, I am thinking that the simplest explanation is what Rich suggested. Check and get back to us so we can see what to do next. |
McMark |
Oct 6 2006, 12:29 AM
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#8
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Lay down at the back of the car, reach underneath, grab the axle and try to bang it into the transmission, then try to bang it into the wheel side. If you hear it hit, that CV is shot.
There has been some debate as to this technique, but I think it works and I've used it on multiple cars. |
MartyYeoman |
Oct 6 2006, 01:20 PM
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#9
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Senior Member Group: Members Posts: 1,520 Joined: 19-June 03 From: San Ramon, CA Member No.: 839 Region Association: Northern California |
Thanks for all the suggestions.
I try them and check back. |
MartyYeoman |
Feb 23 2007, 03:26 PM
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#10
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Senior Member Group: Members Posts: 1,520 Joined: 19-June 03 From: San Ramon, CA Member No.: 839 Region Association: Northern California |
Well, I just completed my rear axle rebuild. I replaced all four CVs and both wheel bearings. Man what a difference. No more clunk. Just smooth power to the ground now. Weeeeeeeeeeeeeee!!!!!!!!!!!!!!!
(IMG:style_emoticons/default/driving.gif) (IMG:style_emoticons/default/driving.gif) |
Eric_Shea |
Feb 23 2007, 05:40 PM
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#11
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PMB Performance Group: Admin Posts: 19,278 Joined: 3-September 03 From: Salt Lake City, UT Member No.: 1,110 Region Association: Rocky Mountains |
Cool... so now we can hijack your thread! Arrrrrrrrrrrrrrrrrgibra.
Rich, what ever happened to your front end issue on your sons car? |
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