ezobens

I have been searching the archives but can't seem to find an answer to my question. My 04' GTO has an annoying axle hop whenever I 'accelerate aggresively' from a stop or shifting under rapid acceleration (car is a 6 speed). Is this something I just have to live with or is there a TSB to correct this condition? For reference, the build date on the door jamb is 10/2003.
Any advice would be greatly appreciated.
Thanks!
Elm.

 

djdub

Sounds like the "think in the trunk" TSB. Call the dealer and ask about it. The fix is... replacing the bushings.

__________________
2004 Phantom Black Metallic/Red leather

GTODEALER

I have recently installed the SLP h.d. sway bar we stock as well as the poly end link bushings and it helped tremendously!!!!!!! I still notice it on blacktop but it has completely stoped on concrete surfaces. We are in the process of becoming a BMR dealer which offers a rear end upgraded mount that is supposed to stop it completly (with sway bar)!!!!!

bsmcall

ezobens,

To help eliminate wheelhop on YOUR Gto, do the following:

1. Check tire pressure (around 32 works for me)
(Many dealers overlooked lowering the tire pressure from 60psi.)

2. Verify that your dealer has performed the TSB regarding "thunk in trunk"
(Have someone inspect the floor pan and differential case for obvious
contact or movement.)
(This involves replacing the differential mounting bushings to prevent
contact of the differential case with the floor.)

3. Verify that the shipping spacers were removed from the front springs.
(They're orange plastic and they don't belong.)

Hope that helps.

ramairws6

my 70 gto 469 cubic inch 10:97 quarter mile had the same problem with street tires, try slicks or leave trac control on ,or for an automatic find the convertor limit side step the brake let it roll a few feet then nail it !!!

ezobens

Well I checked under the car- No orange spacers up front and I don't see any evidence of the differential or driveshaft making contact on the floor pan anywhere.
The noise I am hearing isn't so much a 'Thunk in the Trunk' as the TSB may be addressing, but more of an actual hopping of the axle(s) upon acceleration. Nothing is hitting the bottom of the car, it's the tires bouncing on the pavement.
In the old days, we'd slap some traction bars on the beast, but with the IRS, what are my options?
Thanks!
Elm.

bsmcall

What tire air pressure are U running?
I dropped from 38 to 32, big help.

fwyflyr

I got it too. We all probably do. I'm planning on the SLP sway bar also. Other than tire pressure, don't know what else to do.

GTODEALER

SLP sway bar helps, dont forget urethane end links!!!!! I stock them, the sway bar is $149.00 and the end links are 34.95. E-mail me at gtoparts@alanyoung.com I'm a SLP dealer and a Procharger dealer and in the works of a BMR dealer so I should have you covered at all angles!!!

ezobens

I'll need to play with the tire pressure to see if that helps-

GTODEALER,
How would a sway bar prevent axle hop?
I'm not an engineer but it seems that sway bays only affect cornering or perhaps if one wheel is bouncing and the other isn't.
If both wheels are bouncing simultaneously, how would a sway bar prevent it?
Thanks!
Elm.