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Yes, it has a car seat
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Ok - I'm up and can't get back to sleep and got to pondering wheel hop of all things. Here's some random thoughts / questions...
1) Does breaking traction cause wheel hop, or can you get wheel hop from a hard launch that causes you to break traction (ie. which comes first, the chicken or the egg)? I've only experienced it when I'm playing and trying to break the rear end loose. When I'm feathering the throttle to accelerate quickly, I've managed to avoid any wheel hop unless I break traction first. That being said - I'm not at the track or really pushing the launch that hard, so I'm wondering what others experiences are.
2) Traction control. Can you access the controls of TC through HPtuners or any of the other aftermarket PCM tools? I know the guys who've compared at the track say that TC makes you slower. Now, would that be the same if you could turn off say one or two of the 3 channels? Even better might be if you could tune how / when those channels come on based on what the sensor says? It just seems like if the TC were optimized (which the numbers suggest it isn't) it could be a heck of a tool to get consistantly fast acceleration.
Dan
 

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The best explaination I heard was the a-frame linkage has rubber bushings and when you launch real hard the bushings compress. As the tire breaks traction the bushings return causing the tires to hop. Then the tire returns to the ground and the bushings compress and... you get the idea.

I get wheel hop if don't spin the tires hard like a 3k dump. Second and third gives me wheel hop all the time cause I can't get enough wheel spin.

Interesting question #2. Maybe someone has an answer.
 

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May I quote you on that?
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I believe the Bosch T/C is an independant module, but perhaps someone with a manual could confirm.
 

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wheel hop is caused by both axles abilitys to move independantly from each other, once the axles get some torque though them the tires actually bounce off the ground slightly and this is what you feel during wheel hop. I found rear tire pressure at 24psi I get ZERO wheel hop just lots of tire spinning.
 

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Knight Errant
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Angles

GMH GTO said:
wheel hop is caused by both axles abilitys to move independantly from each other, once the axles get some torque though them the tires actually bounce off the ground slightly and this is what you feel during wheel hop. I found rear tire pressure at 24psi I get ZERO wheel hop just lots of tire spinning.
I believe a change in the angles of the half-shafts can help too. Right now the angles at both ends are sort of conducive to it. Hard durometer neoprene bushings couldn't hurt either. The Vette folks may be some help here with ideas. They had issues sorting out their IRS in early models. There is a replacement rear cover and mount assembly for sale from Australia that is said to dampen the problem quite a bit and also provides for added fluid capacity while maintaining the proper level. The current hopping and resultant loading and unloading cycles have to be murder on the half-shafts and driveshafts...
 

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GTOholic
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I posted this in that other wheel hop thread, but here it goes again...

I've had bad wheel hop in two situations. Doing an aggressive 1-2 shift on the stock tires and doing a burn out at the track on drag radials. I do not get wheel hop during the 1-2 shift on the drag radials or on my new Toyo T1S 275/35/18's. I sometimes get that very satisfying "bark", but no wheel hop. The "burn out wheel hop" is probably because my tire pressure was too high and I don't know how to drive. I'm learning.

P.S. I have the HP Tuner software and there is no provision for modifying the Traction Control. It must be a seperate module with its own computer.
 

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Wheel hop murder on parts.

Old Goat said:
I believe a change in the angles of the half-shafts can help too. Right now the angles at both ends are sort of conducive to it. Hard durometer neoprene bushings couldn't hurt either. The Vette folks may be some help here with ideas. They had issues sorting out their IRS in early models. There is a replacement rear cover and mount assembly for sale from Australia that is said to dampen the problem quite a bit and also provides for added fluid capacity while maintaining the proper level. The current hopping and resultant loading and unloading cycles have to be murder on the half-shafts and driveshafts...
I used to have a 79 Plymouth Fire Arrow with the 2.6. It wheel hopped so bad that it broke the cushion springs in the clutch disc. The shifter moved side to side about 3 inches. I fixed it with cheap slapper bars. They worked great until the one on the left side broke. Then the car lifted on the right front, looked like it was a monster drag racer.
 

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Knight Errant
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T/c

FLORIT said:
I posted this in that other wheel hop thread, but here it goes again...

I've had bad wheel hop in two situations. Doing an aggressive 1-2 shift on the stock tires and doing a burn out at the track on drag radials. I do not get wheel hop during the 1-2 shift on the drag radials or on my new Toyo T1S 275/35/18's. I sometimes get that very satisfying "bark", but no wheel hop. The "burn out wheel hop" is probably because my tire pressure was too high and I don't know how to drive. I'm learning.

P.S. I have the HP Tuner software and there is no provision for modifying the Traction Control. It must be a seperate module with its own computer.
Just use the T/C button Sam. It's not only resident in at least two computers onboard, but also involves the ABS module. They probably left it out because it can be turned off or on.... I have found tire pressure to be very important, too high, and you hop, too low and you fry and go nowhere. You'd think it would be the opposite. The different composition and tread design of tires might have a lot to do with it too. In MHO, the cure will come from a combination of things including bushings and the new rear end cover and mount being offered changing the end angles of the half-shafts. Our friends in OZ will be our best resource for information on this for now. ;)
 

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THE ROKET WAS SOLD ON 6/22/14
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This happens on an aggressive launch or acceleration, Right? Well, I just had that "wheel hop" problem fixed. Who ever mentioned the bushings was right. I had to go through The Pontiac Center to get it authorized. The dealers knew nothing about it, because it was only a bulletin not a recall. Pontiac was hard to work with too, and was kind of "pissy" I knew about it. *This problem was in another thread, but the fix was different, but in the same area.* Don't let them talk you out of getting it fixed!!!! You might have to take the service manager with you to prove it happens (like I had to do)( the guys hair was gray when we got back from the test run, it was brown when we left...lol). Be firm with them!!

They added two Retainers P/N# 90447991, 2 Bolts P/N# 92038482. It fixed the problem perfectly. I wouldn't let the mechanic test it, I told them i'll let them know if it was fixed....

ROK
 

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ROKS ROCKET said:
This happens on an aggressive launch or acceleration, Right? Well, I just had that "wheel hop" problem fixed. Who ever mentioned the bushings was right. I had to go through The Pontiac Center to get it authorized. The dealers knew nothing about it, because it was only a bulletin not a recall. Pontiac was hard to work with too, and was kind of "pissy" I knew about it. *This problem was in another thread, but the fix was different, but in the same area.* Don't let them talk you out of getting it fixed!!!! You might have to take the service manager with you to prove it happens (like I had to do)( the guys hair was gray when we got back from the test run, it was brown when we left...lol). Be firm with them!!

They added two Retainers P/N# 90447991, 2 Bolts P/N# 92038482. It fixed the problem perfectly. I wouldn't let the mechanic test it, I told them i'll let them know if it was fixed....

ROK
OK, your serious? You got this fixed at a dealer and there's a bulletin?!

I think there are some people here that work at GM dealers. I wonder why they didn't know about this bulletin. I guess I have a new quest today :)
 

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Maybe it's just me, but I do not get wheel hop that bad. I'm either going or going up in smoke!
 

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Yes, it has a car seat
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Discussion Starter #13
The TSB you are discussing is actually to fix the 'thunk in the trunk' problem. Recently sold cars 'should' have this fixed already - the TSB says to fix the cars on lots before sales if the VIN is appropriate.
It may indeed lessen wheel hop to some extent - but it by no means eliminates it. As stated I still only have experienced wheel hop when I'm doing burnouts - not on actual hard launches - but I've had the bushings added and it's not a hard fix. Search for 'thunk in the trunk' on this board and you will find it.
Dan
 

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THE ROKET WAS SOLD ON 6/22/14
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mlc said:
OK, your serious? You got this fixed at a dealer and there's a bulletin?!

I think there are some people here that work at GM dealers. I wonder why they didn't know about this bulletin. I guess I have a new quest today :)
Yes I did get it fixed at the dealer. Here's what they call it:

E9407 INSTALL REAR INSULATORS
1674 WG94
Then the rest of the parts that I listed before. This is for cars built prior to Vin Break # 4L246712. The original TSB # was 04-03-09-003, but that number is wrong. It did get the rep to understand what I was talking about, because that number is for clunking noise in the trunk. That turned out to be THIS problem. I hope this helps......
(she wouldn't tell me the new #, she said the dealer has it now)

ROK
 

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Growing up is an option
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i wonder what the build dates are for the people experiencing bad wheel hop? my TPW was 3-10-04. i've done a couple of massive burn outs with no hop at all and lots of 1-2 tire spinners. tires are at 35#
 

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ROKS ROCKET said:
Yes I did get it fixed at the dealer. Here's what they call it:

E9407 INSTALL REAR INSULATORS
1674 WG94
Then the rest of the parts that I listed before. This is for cars built prior to Vin Break # 4L246712. The original TSB # was 04-03-09-003, but that number is wrong. It did get the rep to understand what I was talking about, because that number is for clunking noise in the trunk. That turned out to be THIS problem. I hope this helps......
(she wouldn't tell me the new #, she said the dealer has it now)

ROK
If were talking about the 'thunk in the truck' then I've had this done.
 

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svede1212 said:
i wonder what the build dates are for the people experiencing bad wheel hop? my TPW was 3-10-04. i've done a couple of massive burn outs with no hop at all and lots of 1-2 tire spinners. tires are at 35#
You wont get the wheel hop when you do a massive burn out. The wheel hop occures when you you start hard, just enough to break traction.
 

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Discussion Starter #18
mlc said:
You wont get the wheel hop when you do a massive burn out. The wheel hop occures when you you start hard, just enough to break traction.
Mine's exactly the opposite. The only wheel hop I've ever gotten - before or after the 'thunk in the trunk' fix - is during burnouts. I've never gotten any hop on heavy acceleration when I'm just breaking traction - T/C off or on.
And for the 'thunk in the trunk' fix - IIRC the fix date was early march - so a 3/04 build date 'should' have been fixed before you took delivery.
Dan
 

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THE ROKET WAS SOLD ON 6/22/14
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DANSLS1 said:
Mine's exactly the opposite. The only wheel hop I've ever gotten - before or after the 'thunk in the trunk' fix - is during burnouts. I've never gotten any hop on heavy acceleration when I'm just breaking traction - T/C off or on.
And for the 'thunk in the trunk' fix - IIRC the fix date was early march - so a 3/04 build date 'should' have been fixed before you took delivery.
Dan
Dan, I started this post, and mine also hopped at burnouts, plus when I shifted hard into second or third and break traction I would hear a "clunk" as if the tire bounced up and hit the wheel well. Plus this car was built 12/03, I took delivery of it in March. They fixed the problem and it never has happened since.

ROK
 

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GTONEWB
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Hi All!

Got one quick question, is the wheel hop TSB the same as the "thunk in the trunk" one?

GTONEWB
IBM M6
 
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