JB00SS

yeah i know i did 4 things at once but i had the car up on blocks and didnt feel like jacking it up so many times. sorry guys i got lazy

sheikss

iTrader: (11)

Have you replaced the trans mount with a polyurathane bushung? I have the exact same problem with my car. I've done a 12 bolt and all the bmr stuff, I've had shops check the pinion angle and they all said it was good. I've called around and people have said my trans mount could be the problem. My dad has a huge deal from gm talking about phasing angles and all that. When I get it figured out I'll let you know what fixed mine

JB00SS

yes i had an energy suspension polyurathane mount in the car and swapped it out for the stock one as well as did 3 other things.

ninobrn99

iTrader: (8)

mine isnt lowered and it does it at all speeds. if there's load on the drivetrain, it vibrates. anyone else have it down low?

XpEdItIoUs

iTrader: (44)

Thats backlash if you hear a woom noise when you let of the gas. You need to shim it right to fix that.

JSmee99T/A

iTrader: (15)

Same boat here I posted this in another forum and havnt seem this one for some reason and it started 3 months ago. I have a 99 A4 ta and went from 2.73's to 3.73's along with the axle shafts being replaced. I had nothing before that and after I got it done the vibration is there on the highway goint 70 + and the throttle position depicts the tone or pitch of the vibrations like whether i lift off or push it a little. I replaced the u-joints and rotated the driveshaft....nothin doin so far. It sucks so bad, i do need new tires but i dont think its that. ill have to check the neutral thing cause i cant remember how that affected it. i feel you guy's pain.

jyeager

When you changed your gearing, the driveshaft began to spin faster than it had before. That would be the first thing to check. Take the shaft in to have it balanced at a competent machine shop.

JSmee99T/A

iTrader: (15)

There isnt to many competent places around here..unfortunatly. Thanks though i hope it will be as simple as that.

JB00SS

well my problem is not fixed the "wom wom wom" noise is still there but is alot quieter than before and the vibration is still there. I drove the car to work yesterday and it started back. up on jack stands now and when i spin the DS there is a squeak from the tailshaft everytime. and i have some play in the driveshaft when i push up on it. Has anybody ever had a 4l60e tailshaft apart?

edit: I have just called 2 local tranny shops and both have ask me "how do you know it is in the tranny?" well i dont! the guy told me to unbolt the tranny from the flywheel and see if i still have vibration??? WTF like i am going to go through all that work! I kinda see where is was going with it cause hell it could me engine vibration??? Both guys said this: that there is nothing inside the tailshaft that could cause a squeak. Both told me that is u-joints squeaking when i spin it. Also unless it is blowing fluid everywhere then the seal/bushing is still ok.

I am totally f**king confused now...

silverlt1ss

is there any play ware the driveshaft slips in the tail shaft??? there should be very little and theres more than your think you should replace the seal thats inside the tail saft. there should be 2 seals in the tail shaft. the rear one which is visable and the one inside. it's about 2 inches long and the yoke rests inside of it. i never had an f-body tailshaft apart but they should be the same.

StripedZebra

iTrader: (6)

Ok guys i have a video of my wom wom and want to comfirm if you guys have the same thing. Just turn up your volume if you dont notice anything.

http://video.google.com/videoplay?do...11462900636130


Also, my friend said that we should disconnect my DS, and then run the car on jackstands and see what happens. Then we could find out if its from the DS/rearend or something ahead of it. Sounded ok, but i dunno if i dare.


CHECK OUT THE VID!!!!

1QUIKWS6

iTrader: (61)

He would be talking about the tailshaft bushing. Directly behind the rear seal on the tailshaft extension housing is a pressed in bushing that locates your DS front yoke shaft as it slides over the output shaft and into the tailshaft. If this is worn due to any number of reasons (bad u-joints, incorrect pinion angle, tranny alignment with rear side-to-side, etc) it can allow a lot of slop which will create a vibration. If this happens the DS can move up & down or side to side within the end of the housing and wear the bushing even more.

I replaced my tailshaft housing with a new one when a sponsor had them for sale here cheap just to rule out that problem. You could just remove the housing and press in another bushing instead but the cost was low enough when I bought to out weigh the trouble of pressing in a new bushing.

Once you remove the bushing you will see that the output shaft of the tranny is relatively small diameter all the way thru the tailshaft housing length until it gets to the splines at the end. This shaft is supported at the tranny body end as it exits - but the only support it gets to ride true at the DS end is the interface between the DS yoke sliding over the output splines and then locating off the tailshaft bushing. Seems like a fairly crappy/unreliable design especially for a car that is modded with alot more power. You would have thought they would have a rear bearing in place to support the rear of the shaft instead of relying on a simple bushing.

-Jay-

JB00SS

[QUOTE=StripedZebra]Ok guys i have a video of my wom wom and want to comfirm if you guys have the same thing. [QUOTE]

yep same thing i am chasing down...

jyeager

That's certainly not a high enough frequency to be related to the rear end or wheels. It sounds more like it's in sync with the transmission or exhaust pulses.

We don't have stereo hearing from your video, was the noise coming from the rear of the car or the center? I'm guessing center. It could be harmonics in the exhaust. It could be rattling around against something. Any aftermarket exhaust components should be checked for interference. All mounts should be checked. Make sure nothing else aftermarket comes too near any portion of your exhaust.

StripedZebra

iTrader: (6)

Its in the center consol area. Putting in Pacesetter LTs and ORY as we speak so ill see if it changes

durrettcustoms

iTrader: (2)

I think my problem lies with the energy susp. trans mount that was the only other thing i had changed when i had the flexplate installed.....

Dragula

iTrader: (5)

SAME PROBLEM HERE!!! 2 years ago I got a Strange 12 Bolt, Spohn adj. TA. I've rotated tires, used different rims and tires, checked, rechecked, rechecked, etc the pinion angle. I even checked the transmission output shaft angle. The tranny is 4 degrees down towards the back of the car, so I angled the Pinion up 2 degrees. Before that I tried shimming the tranny by 1 inch with no luck. I've had the pinion angle in every 1/2 degree increment from -3 to +3. +2 is the best for my tranny output shaft angle.

When I first got the rear end I had a really bad noise from the factory, so I had a shop replace the bearings and gears. They didn't do it right and I had to have re done by a professional. This still didn't fix the problem.

I also had a thud noise when starting from a stop in forward and reverse. The original shop that installed it, found that the front shackle on the TA was loose. Once they tightened it, the thud went away.

I hope the wraping on the driveline from the loose shackle didn't mess up my tranny output shaft.

I plan on looking into the vibration again once the salt is off the roads.

ninobrn99

iTrader: (8)

has anyone put the stock torque arm back in to see if that helped?

Dragula

iTrader: (5)

I haven't put the stock TA back in. I'm sure that will get rid of some of the noise since it won't be rigidly mounted to the unibody.

I think a few people on this thread are having the problem with the stock TA.

ninobrn99

iTrader: (8)

yeah, i know there are some with the stock TA, but it was more directed to those with a spohn. I should've edited it when i was going to. I dont think its the transmission bushing cause mine didnt do it after the swap..nor did i get the wha wha noise everyone seems to be having.