1SlowFormula

Hey everyone I am new here, I have done a few searches without answers to my questions below, and not sure if this is the exact place for this but it includes a bunch of things listed in the description for the section...

I am getting a strange vibration and not sure if it is wheel hop or not...

My entire suspension is stock minus removal of the front sway bar, and the car only has 79K miles...

For the past few thousand miles, about a year, the rear end and rear suspension has been noisy, with a lot of squeeks and creaks while driving or jacking up the car. In this same time frame the rear end started going out and doing single wheel burnouts and spinning on the street. The gap in the wheel well remains about the same with about 4.5 inches from the top of my stock wheel to the bottom of the wheel well so I don't think that springs are sagging...

Recently I have developed this strange vibration when I accelerate hard, and after the 1-2 shift. It feels like I am driving over the rumble strips on the side of the highway. I think this is wheel hop and also due to the single wheel slipping. The strange part is I have felt wheel hope in a lot of other cars and it has never felt like this, it was always a jerking chirp-chirp-chirp and you could feel the rear actually hop.

So is this a strange type of wheel hop or is my rear actually almost completely gone, and causing this?

BeachZ

iTrader: (2)

The single wheel burnout part makes me think your posi is on the way out.

CW00BlackTA

iTrader: (31)

Lubricate your rear suspension joints and get your rear fixed. Wheel hop is something you definitely feel when the rear end of the car bounces up and down.

1SlowFormula

So I guess your saying that the rear suspension is the cause because it needs to be lubed? I had lubed it about 6 months ago and the sqeeks and creeks didn't change much, I guess I can do it again but I normally do it once a year (I normally put less then 4-5K miles on the car per year)...

I know the rear is going out, but I was trying to figure out what this vibration was. I don't really have the money to throw at the car and hope that was the cause, I know I need suspension and a rear, but no way can I afford both right now. It would also suck to spend $1000 for rear suspension to find that the vibe was the rear telling me it was about to give up completely, or vice versa, spend $3k on a rear just to find I stll can accelerate because the the suspension is toast...

sdm1234

iTrader: (8)

Dude, to me that sounds like your clutch is slipping. It'll do that under hard acceleration. You're probably losing your diff. as well, but it definitely sounds like clutch rattle.

ZeeVert

I have to agree.

I never thought of it as running over a rumble strip, but that is exactly the feel I get w/ my F150, and it's definitely the posi-rear. It's at it's worst when turning and moderate acceration.
Now my ignorance... how hard is it to inspect the diff?

And you mentioned removing the sway bar... you did put one back on?

Super Speed

iTrader: (8)

Do a giant burnout then get off your car and look if there's 2X stripes then its not your posi sounds like its your rear end or clutch though

1SlowFormula

Well the A4 doesn't have a clutch, so I guess this narrows it down to the rear...

I haven't had a chance to do a burnout, living around a big city that cops crack down on racing it's hard to do that... But I do accelerate hard from lights, and today I was coasting to the light and I was the first car, and it turned grean and I nailed the gas, i know it was spinning, and I really felt that vibe and it was quite fierce, and definitely felt like wheel hop so I think it spun both a little...

ZeeVert

Not trying to be a smart-*** (maybe a little)... but autos actually have several clutch packs in them. It is possible that one or more of them is slipping, but unlikely.
Sorry that I don't know more about rear diffs. It may be as easy as trying to change the oil in it.

1SlowFormula

OK yeah I know they have clutches too, but I seriously doubt that is the problem in an A4...

I guess I should have mentioned some of the things I know is wrong with the rear, since I am new here you guys should be brought up to speed...

Well the fluid is only about 10K miles (2yrs) old, and I had the limited slip additive put in when I did that. I needed to change it while on a trip to Florida, because somewhere in Georgia it started whinning, clunking, and acting up. The clunking was due to a broken tranny mount from screwwing around earlier launching in trafic due to the stop and go hell getting into VA from DC. The rear on the other hand had a little metal in there and I wasn't sure where it was from, and a lot of guys said that the clutch packs in the rear could be going out so I just dismissed it and started to save for the rear to be replaced...
Then about a year later I started getting a seriously bad grinding noice when making a left hand turn, found that that axle was shifting out a little and grinding the rotor on the caliper, I made a few shims and shimed out the caliper bracket to stop this and came to the conclusion that the C-clip on that side is wearing down causing the axle to move a little. I guess I found where that metal inthe fluid came from...
Then then a few months ago, about another year later, the posi has not been holding. I could only feel and see one wheel spinning from time to time, this had progressively gotten worse...

All this tells me I need to replace my rear, so that I know that, I just can't afford it right now. But out of no where this vibration started, and I am trying to verify if it is the rear or wheel hop...

z28bryan

iTrader: (7)

Wheel hop is when your wheels hop on the pavement when you do a burnout. Do a burnout and have someone watch your wheels at the same time outside of the car.

Arrison24

i realize this thread is ANCIENT but i was wondering....whats the recommended gear oil and posi additive i should get for my 98 trans am

Luder[PAK9]

WTF, n00b? You bump a wheel hop thread to ask that? Figure out what kind of diff. you have, then search for "gear oil." You should find your answer right quick.

keliente

iTrader: (22)

75w90 or 80w90 dino oil, and add a tube of GM limited slip additive if you have an auburn differential.

Wow, very welcoming.

1SlowFormula

holy crap, boy was this an old thread. When I first saw it and saw that I started it, I was wondering who stole my username, then realized it was a few years old...

Glad you got your answer Arrison24, at least you were searching, that's a good start, best of luck...

bhuss

i have an '02 t/a. i think i have the same problem as you did years ago. when i take off hard, it feels like wheel hop. worse when turning it seems. did you ever nail down a cause?

1994Z28Lt1

iTrader: (1)

wheelhop is violent, if you have to ask whether or not your experiencing it then its not a problem its something else

bhuss

what its doing is violent, i just got worried when reading about rear end problems.
my third gen iroc never wheel hopped so i haven't felt it before.

1994Z28Lt1

iTrader: (1)

so you still have the stock LCA's?
i know on my stock car, it only had about 75,000 on it at the time but the stock bushings in the LCA's were completely shot especially the passenger side. i replaced them with some aftermarket LCA's and it cleared up a lot of problems i was having, less tendency for wheelhop for one thing

bhuss

yea, it's all stock, with about 80000 miles on it. i probably need to look in to updating my suspension.
-thanks.