hpjunky98

iTrader: (3)

Heres the deal, I have a 1998 z28 with 140,000 miles. when i got the car, it had all factory suspension, and being a noob at the time, my first mods were the ones easy to install. so far, suspension wise, i have UMI SFC / T/A with polly mount / poly/rod LCA/PHB. the car hooks ok, but damn with 140,000 miles on her she is no longer fun to drive. The shifter moves about 2 1/2 inches during acceleration, and the ride is horrible with a capital H. Im hoping that poly motor mounts and a 1LE tranny mount will stop the first problem, and then a set of strano springs and revalves along with some poly swaybar bushings will make her ride better. Please provide some input because i love this car, but im just not enjoying driving it anymore, and thats the whole point i purchaced it.

edit: also any time the car revs up there is a really strong vibration. should i balence the driveshaft and replace the ujoints, or would the tranny/ motor mounts take car of this some?

slick1851

U joints in my DSM were horried and made alot of vibes in the car, I would replace them anyways.


I would suggest replacing other rubber peices with newer ones since you have a bit of miles

hpjunky98

iTrader: (3)

would i be better off replacing them or ditching the rubber all together and getting polly mounts? thats actually what i was talking about before with the swaybar mounts...at least i think they're the only rubber parts left along with the other mounts i wanted to replace.

mike#9

iTrader: (3)

Is your car a manual or auto?? When you say that it vibrates when reving....is that when you are sitting still or driving? Could be a flywheel if you are M6.

rocket22

iTrader: (2)

Well 1st the ride,ride is 99% shocks,so new shock will help the ride Bilstein revalve's will help abunch,lowering springs are going to firm up that ride,so it won't feel soft with them.

The shifter moving sounds like a worn out shifter,new bushings wil help alittle too.

The 1le tranny mount has been superceded to regular tranny mount,so go with a enegry suspension mount.

slick1851

Some poly bushing will cause bind, so its not a good idea to replace everything

But it would be wise to replace motor mounts,trans mounts, with poly units

I would go with a Pro 5.0 shifter because it has a great soild feel.....

Search isnt working so im sure others will chime in

subtlez28

iTrader: (15)

I think the shifter movement is due to a worn out or broken trans mount. I had same issue w a 3rd gen I had. Use rubber if vibration bothers you, as poly will transmit more vibration. If you want to firm it more (assuming its an M6) get a short shifter, to replace the stock one (even the factory Hursts have big a bushing on the shifter itself). If u have a hurst just buying the replacement short stick will make it feel better IMHO--->best $20 I've spent on the car!
I don't know if motor mounts would be worth the $ and effort...I'd start w a tranny mount.

I think U R on the right track w new shocks also...but my 2 cents is Koni S/As R worth the $. You can adjust them to suit your personal ride tastes, and spring rate (and lower the car w stock springs).

As 4 the vibration, does it happen when revving while not moving? If it only happens when U R moving, U R also on track w the U-joint replacement plan. Thats alot of miles (and probly hard ones) 4 them.

z_speedfreak

iTrader: (3)

shocks and springs is prolly what your looking for. but i cant stress this enough! if your shifter has that much play in it ditch it! my loose shifter costed me $1600 to get my tranny rebuilt, i always thought my failing synchros were from abuse from the previous owner, turns out it was that stock sloppy pos hurst shifter that was doing the damage and I only had like an inch or so of movement in mine..
of course it may be the mounts or somin else in your case but better safe then sorry i say and a pro 5.0 is nice and fun

gun5l1ng3r

What is the easiest way to change U-joints?

hpjunky98

iTrader: (3)

ok thanks for all the replys let me clear up a few things. my car is an M6. the vibration is only there when i accelerate while moving. the shifter doesnt have play in it at all. what im talking about is when i floor it, or even accelerate a little, the shifter rotates to the right, meaning that the whole motor is moving...alot. this is why im thinking trans mount/ motor mount replacment.

i will get the u-joints replaced and the driveshaft ballenced as soon as i can. I think ive decided on getting koni SAs and some polly swaybar mounts as well to make the ride alot better.

one more thing though, and im not sure if this is the right area for this because im not sure exactly what the problem is, but if i try to launch the car or just give it more gas when im just starting to move, the car kind of pulses a bit... thats the best way i can explain it. im thinking this has to do with the amount of slin the drivetrain, but im not sure... anyone got other ideas? i just replaced the clutch with a stock one( not my idea) so i dont think its the clutch.

thanks for the help!!!

94z28L

iTrader: (4)

sounds like you got it mostly covered.

as for the latest problem mentioned could that be that car going in to tire shake? or is it the revs coming up and down? can you tell where its coming from?

when i read the title i thought you meant the car wasnt fun to drive because you were bored if that was the case i was gonna tell you to come out here and drive in the snow lol

BigT2002

iTrader: (2)

Shocks and springs been upgraded at all? If you've never changed the shocks I bet thats a big thing right there