gmoran1469

I've got a 09 GT and I've done a few mods to it:

Koni STR.T dampers
Steeda Sport springs
Steeda HD strut mounts
UMI 1055 adj. w/ rod ends
Steeda 4105 Adj. UCA
Steeda 4406 LCA
I run 18x9.5 wheels wrapped in Nitto NT-01's (24/7)

I had been having a loose feeling while going forward and reverse for a while so I took the stang into the local shop and had them put it on the drive up rack to see what the deal was. Blown bushings was one of the problems so instead of replacing stock stuff I upgrade and got some Steeda LCA's and an adj. UCA.

Got everything installed, no problems there, I can tell everything is much tighter thanks to the urethane bushings but I still have some sort of clunk or loose feeling in the rear end. I popped my rear seat out so I could hear what was going on better and it definately sounds like either rubber rubbing, or something down there has worn out where a bolt is and there is play in it.

I am curious what the mount is that connects the UCA to the rear-end housing at the top of the rear end. When I was under there installing the UCA it seemed like it was a rubber bushing and I couldn't get a great view of it but it certainly didn't seem like it was in the greatest of condition.

I get a definate lunge forward from the car at around 2500 RPM's in 1st gear when I let off the gas and it feels like a bolt in a bolt-hole that is too big for the bolt, that's the best way to describe it.

I can replicate the noise/feel by going forward and reverse, not side to side and I can also replicate the sound when coming down off my driveways slope at the end (have to go slow so I don't scrape).

I thought that maybe I had not installed the spacers that came with the Steeda UCA but I doubled checked and everything is installed properly. Checked and regreased the panhard to make sure the lock ring had not come out and it is still good to go as well.

Any thoughts as to what I should be looking at first to fix it?

I will be putting it back on the rack soon to take a look at it again.

gmoran1469

Update:

Put it back on a rack and looked at it again.

The only thing I can see that could possibly be causing the problem is the rear housing bushing. The transmission shop said there is nothing wrong with the rear end or the transmission.

Is that a common problem for people? To clarify I am talking about the rubber bushing that is pressed into the top of the rear end housing. Where the UCA connects to the rear end.

loots06

I know you said the rear but could it possibly comming from the front strut mounts.

gmoran1469

I'll double check but they haven't given me trouble since I installed the Steeda HD mounts instead of the stock ones. It has a distinct feeling of coming from the rear of the car.

I know that the install of the UCA and LCA's w/ urethane bushing has exaggerated the noise, but not the feel. I can only replicate the clunking feeling while in gear, moving around 1500 rpm, and hitting the throttly slightly, then releasing it right after the car start to accelerate. I get a lurch forward like you would expect but also a feeling like something is loose and then it catches. Like a loose bolt (everything in the rear is tight and I will double check the front). I would think if it was the front I could replicate the feeling by hitting the brakes as well but I can't, only when I use the throttle.

The trans shop I took it to, I know the guy who owns it and I had asked him to give the car a complete once over. Even though he specializes in trans, he also does some drag racing and knows a good bit about cars so I asked him to give it a once over and to drive it and see what he thought. He said the only thing he could think of that would be causing that problem is the rear housing bushing.

gmoran1469

Front strut mounts aren't causing the problem =\

The rubbing noise I figure is just from the LCA's and UCA Urethane bushings rubbing, not really worried about that, it's the jarring motion and looseness I am worried about.