Gearhead1

I'm sure it's getting louder because you're unloading the drivetrain. What that means though.....???? What would more more noise while coasting....anybody????? Maybe the pinion bearing???

jyeager

Well, just guessing here, but if the sound does change (as well as the intensity of the vibration) between being loaded and unloaded then it's got to be in the drivetrain and not the tires...

Does the vibration coincide with RPMs or vehicle speed? For instance, does it vibrate the same at 2000rpms in every gear, or only when the vehicle speed gets to a certain point?

If it's tied to vehicle speed it's somewhere behind the trans (or in the output shaft).
Assuming that's the case then it could be the tailhousing (cracked?), transmission mount, output shaft, U-joints, pinion or pinion bearings, axles or axle bearings.

It's not just an imbalanced driveshaft or a problem with the balance of the yoke or it wouldn't change with load.
If the pinion angle is out of whack, this could still be it. Because the pinion angle changes depending on drivetrain load, especially with stock and worn components.

Mike2000Z28

I'm havin the New Era crew put a set of wheels and tires that they have around the shop to check to see if on the dyno the vibration is coming from my wheel/tire combo. Since pulling the car out from storage I placed the rears to the front and now the steering wheel has a vibe in it more then last summer before putting it away. I still think that the rear had some bad vibes it. I'll let everyone know when I get my new tires if they need to do that or get new rims....

Just by chance how many have aftermarket wheels from OE Concepts from Sarasota,FL.

StripedZebra

iTrader: (6)

Its definately worse when coasting. Im gonna have a tranny shop check out my car sometime soon...

JB00SS

it only does this at speeds between 50-70. does not do it while going through the gears. I still havent done anything yet. been busy this week hopefully by the weekend i can get something done. I have been thinking about getting a UMI TQ arm and get it off the tail shaft, but i am also thinking about TSP x-pipe setup and need to find out info on that and make sure the two pieces will work together.
When me and my buddy did check the yoke and DS the other night i did have a little play in the tailshaft but we didnt think it was out of the ordinary i mean when i lifted up on it there was just a smiggen of play. it could possibly be that bushing/bearing in the tail shaft??? it doesnt look like it is an easy fix besides throwing the wallet at it!

jyeager

Off-hand I don't know how much endplay there should be in the output shaft, but this could definitely be the problem.

JB00SS

i am also going to check the pinion angle before i take the driveshaft out. i need to search to find out what it should be set at and how to do it properly. driveshaft and pinion angle will be first, then change front tires, then tailshaft or rear end. the tailshaft is not leaking also. no drops no sign of fluid.

XpEdItIoUs

iTrader: (44)

Has anyone acually taken there rear cover off and checked for backlash on their ring and pinion, because this will cause vibration at higher speeds.

JB00SS

yeah about 4 times 3 weeks ago when my buddy installed the gears. he had it we went for a ride he didnt like it and we jacked it back up and took the cover off and re-shimmed. done this 4 times that night untill he liked everything. he has come back over and checked the lash from the yoke just recently. everything looked good when he installed it and he explained everything too me and showed me everything as he installed them. Hell he's been my best friend for years i have all the faith in the world in him! And i am sure that if we cant get it narrowed down he will pull the cover and check it out again.

jyeager

If the tranny output shaft were wobbling all around it would almost certainly be throwing fluid past the rear seal.
If the tailshaft were cracked or broken then it seems like fluid would somehow find its way out.
Have you checked the tranny mount? That poor rubber thing takes a lot of abuse from the torque arm stresses being thrown at it.

One thing to try because it's easy is to take out the driveshaft and turn it 180 degrees and reinstall. Sometimes there's a little balance problem in the pinion, a little in the driveshaft, and maybe a little in the u-joints and if they all line up right, the unbalance is all together. Turning a few of those items 180degrees out can sometimes cause some of this vibration to cancel itself out.

Now I don't think this is all of your problem because I can't believe that would cause the severity of the symptoms you've reported.

JB00SS

the tranny mount is an energy supension brand new maybe installed for two months now. I will check and make sure it isnt loose. I will also try your ideal on the driveshaft rotating 180 cause it doesnt hurt to try! there is no fluid leaking/dripping nor is it using fluid dipstick shows full last time i had it out and running. I am going to get out there this evening and try these things and see what happens! wish me luck! I am also going to check the pinion nut to make sure it didnt work it's way loose

indyboom

iTrader: (11)

I just posted a new thread. I just had my rear redone with 3.73 richmonds.. I had a slight pinion noise at light throttle. I owna 00 ws6 and never had it over 80. Well i had my buddy do a alinment too and he said and showed me that the rear was off. the max is like .25 and it was at .26, on the LEFT side.Im not sure on what the term is but he showed me that the lower rear control arm appeared to be bent some..So im looking at some SLP Control Arms, Lower "Heavy Duty" 1982-02 Camaro/Firebird, this may be some of our problems?

JB00SS

i have UMI LCA's and relo brackets that are on my work bench. You should look into them they are a very nice product. I wish i could just take off the rest of the day and go home and start tinkering!

HossZ28

iTrader: (5)

I dont have this vibrating problem yet. But it seems like many of the people are having the problem after lowering the car. What can i do prior to lowering the car to prevent this vibrating.

was thinking about either eibach prolines or hotchkis.

StripedZebra

iTrader: (6)

I had it before i lowered....

CW00BlackTA

iTrader: (31)

Me too...before I lowered.

INMY01TA

iTrader: (1)

I'm puttin on a Spohn TA pretty soon and all these different ways of measuring pinion angle got my head spinning. Since I have no vibration now w/stock TA, if I just measure the angle of the driveshaft and set up the new TA so the driveshaft is at same angle would I be cool?

silverlt1ss

i have a vibration problem. it starts around 70 mph woom woom noise. only happends when i let off the gas soon as i give it a little gas it goes away. i have an a4 and it was totally rebuilt. rear end was also rebuilt with 373's. i installed a used 1le drive shaft about year ago but it seemed to be in good condtion. if i put the car in neutral it goes away so i know it's not a tire. any ideas????

JB00SS

well when i put mine in N it made it worse! But anyway I have good news! I did 4 things friday night while i had it jacked up:
1) lowered drag radials from 24psi to 20 psi
2) took DS out, looked over it, re-installed it. seen nothing visually wrong
3) my UMI DS loop was against the tunnel so i re-aligned it with the driveshat out. this was not visable with the DS in
4) removed energy suspension tranny mount and put rubber stock back in

NO MORE "WOM WOM WOM"!
i hate not having the tranny mount because it did feel real good on launches made the car feel solid, but if it was the tranny mount causing this then i guess i will not install it??? i did drive the car 20-30 miles and it never came back so i am concluding that i have it fixed.

jyeager

Since you did it all at once we'll never know what fixed it. It might be worth putting the tranny mount back in since you really liked having it. You might find it was the tunnel contact with the loop.