[slvrbllt98GT]

After lowering my car, I've noticed that if someone is in the passenger seat and I'm shifting fast at high RPM's that there is a pretty loud clunking noise when I shift and hit the gas hard. It sounds like it is coming from directly below the center column in the car. Seems to do this worse and worse the more weight that is in the car.

I crawled under the car to see if anything was rubbing (exhaust, driveshaft,...), but didn't see anything. There really is nothing directly below the center column. I'm fairly sure this is a result of lowering it since it didn't do it before and gets worse with more weight.

Any ideas would be greatly appreciated!

[product1620]

is it a continuess clunking under load?

[slvrbllt98GT]

It's just a very quick (but fairly loud) clunk noise that seems to occur when I let the clutch out quickly and give it gas. It doesn't occur if I'm just driving normally... only when I'm really getting on it and shifting hard.

I would think that it had something to do with clutch/tranny, but it really does seem to be related to the lowering and how much weight is in the car.

[Ryan Paymaster]

Even though it sounds directly under you it may not be. My car actually makes awkward noises that I have no idea how to explain at all sometimes too.


Did you make sure you tightened everything correctly? I know when I did springs on my other car, a 2000 Cougar I had to retighten back up the bolts on top of the strut towers as they were loose and allowed the strut to move around and make a thunk noise under very specific situations. (In my case, any sort of cranking the wheel.) That and the fact I forgot the top mount part for the rear struts, but that was different. I'm sure you didn't forget to put any parts on the car.

Make sure you installed everything correctly, as nothing really should be clanking transmission wise because you lowered your car. If it IS your transmission or something under there, it'd be an extremely freak occurance that it just started to show itself more after lowering the car. It's kinda of like if you went and watched Dateline NBC one night and your TV died while watching it. Then you assume it was Dateline NBC that caused problems with your TV. Just a freak time for an issue to pop up.

Make sure everything is tight and check the top bolts on top of the strut towers to ensure they are tight and not letting the suspension have room to "play." If you are sure, keep checking. I'm almost positive it's this issue as I had it in a previous car.

[slvrbllt98GT]

Thanks Ryan, I'll definitely give that a try! I know that Les Schwab actually took off the strut bolts when they did the alignment (to change orientation on the CC plates), so maybe they didn't get them back on all the way or something.

Thanks again for the advice!

[slvrbllt98GT]

Well, I tried tightening the strut bolts, but they seemed to already be as tight as they could go.

Any other suggestions? Thanks!

[HMUSN]

hmmm directly under the shifter huh...


take a look at your u joints

[Ryan Paymaster]

Doh! I was really hoping that would be your problem.

I mean my car makes noises under hard shifting too, but that is only sometimes. It's probably the T45 crying for it's life and about to die on me. That and I get a sort of "rubbing" noise sometimes from my undercarriage. I thought it was my exhaust (it wasn't), so maybe I should go under my own car and take a look too.

[Casper98GT]

well how low did you go ? If you go more than 1 3/4 you will need new rack bushings, caster camber plates and a new pinion snubber. When you have all youre weight transfering to the rear that pinion snubber is still at stock height and it may be slamming on youre axle everytime you shift.

Also how about exhaust clearance.

[k2boarder3187]

spend 20bucks and change your transmission mount..it takes about a half hour and its worth a shot...

[slvrbllt98GT]

Thanks for all of the replies. Here's some answers to the questions...

I lowered it with H&R Sport Springs which advertise a drop of 1.6 in the front and 1.5 in the rear. I also left the isolators out, so it's a bit more than that. I did install MM C/C plates, as well as the new bump stop that came with the springs (I'm thinking this is the pinion snubber Casper is talking about). I have replaced the front rack bearings with poly ones (they squeak like crazy when I turn the wheel, but did this also before I lowered it). I've checked all my exhaust and clearance is good with no signs of rubbing.

I may look into swapping out the tranny mount. This has me really confused because I can't get it to do it with just me driving. It's only when I add the extra weight of some passengers.

[ujslost]

I have the same exact problem. I have posted up about it with no responses. Sorry but glad to see someone else having this problem actually now.
Look at your drive shaft and see if there are any really fresh clean or scratch marks on it. Mine does , I put mine on a 2 post lift and seen the drive shaft is actually hitting the bottom of the tunnel on the Ebrake cable crossover. Not constantly hitting but like you said , only when I stomp it with a passenger. I know its axle wrap causing it. And I installed a shorter pinion snubber with my lowering springs, so I know thats not whats hitting. Checked my tranny mount and its good. All I can think of is a set of upper and lower control arms should fix it.

[slvrbllt98GT]

No kidding, someone with the same issue! Well, like you said... I'm not glad it's happening to you, but glad I'm not the only one. :wink

I'm going to check tonight and see if my drive shaft has any marks on it. But you think new control arms would fix it huh?

[MustangMatt96GT]

I have marks on my driveshaft too, but I dont get any noise that I am aware of, but I never have passengers.

BTW what is a pinion snubber?

[Casper98GT]

Just a rubber stop so you dont bottom out youre rear end.

If youre more than an inch then you will start rubbing youre ebrake rivet.

The control arms in the rears make noise when the bolt loosens. I torqued mine down when i first got the car because they let out a clunk. Make sure they are tight because the loosen up on all 8.8 cars, even the front control arm bolts on the lightnings.

[ujslost]

i have the eibach pro kit, so does matt, and hes not got the problem so far.

[slvrbllt98GT]

Well, I looked and sure enough there is a shiny ring around my drive shaft right below the E-brake bracket. Now I'm sure that's what's causing it! Thanks for all of the diagnostic help.

Now I guess the question is what do I do about it? It sounds like installing an adjustable pinion snubber will do it (although it seems like I'd be "bottoming out" on it when banging gears). Oh well, I guess hitting the pinion snubber is better than hitting the E-Brake bracket! So it that pretty much my only option?

[ujslost]

let me know how that works out. or try putting the stock length snubber back on????

[Casper98GT]

why would you put the stock snubber on...thats gonna make things worse. trust me that noise youre hearing isnt from that e-brake rivet getting rubbed. you honestly think a clunk noise is being made by a small ring around it ? You have other problems. I have NO clunk and i have that ring around the DS due to the lowering as well. Im sitting on 2 inch drop. you need to check out the entire suspension.

[slvrbllt98GT]

Thanks for the advice Casper. I'll take another look and see if I can tighten any bolts on the rear control arms like you mentioned. I guess I was just suspect of the ring on the drive shaft because I can see where that's one place that it is definitely hitting.

More to come...