Cobra Rocks! (not a good thing)

[I'LL B Bok]

Hello Fellow Terminator Fans. Need help or insight please. My Cobra will rock (like a side ways see-saw) under hard acceleration in 2nd or 3rd gear. Its not fishtailing...I know what that feels like. The car literally shifts its weight from driver's side to passenger side to drivers side as long as I stay in the throttle. Its not subtle eiter. It likely does it in 4th too but I'm not going to demonstrate this problem going that fast as it feels VERY unstable.

A very brief history:

I have Nitto DRs in rear. Passenger side rear recently collected a nail :fm: I removed it and plugged the tire with a typical pep boys kit. Tire never went flat with the cars weight on it so sidewall was not compromised. Despite this, it seems the rocking started right after the plugged tire went back on.

Discuss.

 

[Y2k4cobra]

You might of shifted a belt in the tire if you plugged it. It happens when you remove a object from the tire and you push in the plug kit. I would of took it off and had it patched. Where was the nail in the tire? If its close to the side wall odds are the steal belt is shifting in the tire.

Or you have worn IRS bushings

 

[TORQJNKY]

I've got the same issue. See attached thread: http://www.svtperformance.com/forum...-piece-wheel-owners-step-rear-end-wiggle.html

I've not done much trouble shooting lately because I've been on travel for work so much. I've checked everything that I can think of in the rear end and can only attribute it to bushing flex thus far:shrug:.

 

[68_GT]

front sway bar delete ? I deleted mine and it's not that noticeable though in straight line acceleration other than the weight transfer.

suspension mods ?

my car felt very unstable until I switched out my rear lower control arms and found the previous owner put too thin of a bolt at the front of one of my stock lower control arms. the bolt had all kinds of marks on it where the LCA was wobbling on it. New thicker bolt fixed the problem with the new MM LCA's.

You could have something loose somewhere ..... lug nuts maybe ?

 

[68_GT]

swap out that wheel w/ repaired tire with a buddys and see if that helps any

 

[I'LL B Bok]

You might of shifted a belt in the tire if you plugged it. It happens when you remove a object from the tire and you push in the plug kit. I would of took it off and had it patched. Where was the nail in the tire? If its close to the side wall odds are the steal belt is shifting in the tire.

Or you have worn IRS bushings

Good point but that be one hell of a shift. The nail was exactly in the middle of the contact patch. Patching was my first plan but was told by 2 places that they wouldn't shave the inside of a DR to apply the patch...and i should just plug it

 

[68_GT]

check the lug nuts of the wheel they repaired

 

[I'LL B Bok]

I've got the same issue. See attached thread: http://www.svtperformance.com/forum...-piece-wheel-owners-step-rear-end-wiggle.html

I've not done much trouble shooting lately because I've been on travel for work so much. I've checked everything that I can think of in the rear end and can only attribute it to bushing flex thus far:shrug:.

thanks for this....researching...:read:

front sway bar delete ? I deleted mine and it's not that noticeable though in straight line acceleration other than the weight transfer.

suspension mods ?

my car felt very unstable until I switched out my rear lower control arms and found the previous owner put too thin of a bolt at the front of one of my stock lower control arms. the bolt had all kinds of marks on it where the LCA was wobbling on it. New thicker bolt fixed the problem with the new MM LCA's.

You could have something loose somewhere ..... lug nuts maybe ?

I have HR race and upper ISO's removed for some time now. I plan to throw it up on stands this weekend to put new ISOs in the rear only (i want more of a rake to the stance). I will go through all components to see if anything is amiss while the irs is dropped. I don't curently get any rattles or pops though.

 

[racebronco2]

Check the rear axle bolt.

 

[I'LL B Bok]

Check the rear axle bolt.

what/where's that?

 

[dezracer]

what/where's that?

Ditto. Its at the Hub. Its a huge Nut. cant miss it.

 

[racebronco2]

Torque it to 220ft lb.

 

[I'LL B Bok]

rear axle bolt size?

Check the rear axle bolt.

ok got this thing apart. there is ALOT of play in the driver rear wheel. passenger side is tight Seems to be at the joint where the axle meets the hub. I want to tighten the bolt but do not know what size it is??

Anyone know what size the rear axle bolt is? It bigger than 1 1/4' and i dont want to keep buying these things till i get one that fits.

 

[JB]

Axle nut is 36MM

If it's been driven very much with it loose you may need a new bearing and possibly hub

Check your tie rods as well (both ends)

.

 

[I'LL B Bok]

timely info..

Axle nut is 36MM

If it's been driven very much with it loose you may need a new bearing and possibly hub

Check your tie rods as well (both ends)

.

thanks much for the quick response :beer:...i'm off to sears...again.