Vibration

WraithTR1 · Mar 8, 2011

I have a 95 GT automatic that has a very bad vibration. It doesn't matter if it's in park, neutral, or in any of the drive positions. Check engine light does not come on. I've looked at the harmonic balancer and visually there does not seem to be anything wrong with it. If I rev the car up it seems to worsen briefly right around 1000 RPMS and then smooths out a little until it drops down to 1000 and shudders a little harder then smooths out a little and rest at around 700 RPMS. Besides the HB is there anything else that could possibly cause a vibration throughout the entire car?

Pale Horse · Mar 8, 2011

Ignition,or motor mount. I would check the ignition first, plug wires, cap, misfiring plug and coil wire, coil itself. Then maybe motor mount.

95-stang · Mar 9, 2011

I would still be tempted to pull the balancer and take a good hard look at it unless there's something wrong at the flywheel end.

CC'S95GT · Mar 9, 2011

95-stang said:
I would still be tempted to pull the balancer and take a good hard look at it unless there's something wrong at the flywheel end.

I agree. the thing could have slipped but look OK.

5litrarag · Mar 9, 2011

How many miles on the car? Is it the OEM balancer?
If its over 80k and you have never changed it, do it now. It needs it and its just good maintenance. Chances are it has spun slightly and you cant see it. It may still spin true, but obviously the weight isnt in the correct place, hence the slight vibration. Get under the car and look at the back side of it...I'll bet the rubber is just slightly coming out.

WraithTR1 · Mar 10, 2011

According to the odometer only 73300 or so, but that broke a couple of years back. Thanks for the help, I've got a couple of other things to check now this weekend.

Paul · Mar 10, 2011

Replace your balancer.

CC'S95GT · Mar 10, 2011

the odometer prob is likely the plastic gear on the back of the cluster.
easy and cheap fix.

Dr Fildo · Mar 10, 2011

+1 Balancer

WraithTR1 · Mar 16, 2011

So I got up under the car and it is definitely the balancer. Going to order a new one Friday when I get my paycheck. Do you have to remove the radiator to replace it?

CC'S95GT · Mar 16, 2011

It depends on the size of your puller.
I didn't need to pull my rad. but other did.
You will definately need to pull the fan and shroud.
Don't forget the big washer under the HB bolt. Otherwise the puller won't work.

Paul · Mar 16, 2011

If you don't have a decent puller and impact wrench, this is one of those things that's often just easier to have a shop do. I even HAVE the tools, but it's a pain in the ass so I'd even consider just having someone do it. They can knock it out in minutes.

Paul.

Pale Horse · Mar 16, 2011

Glad you found the problem.

WraithTR1 · Apr 9, 2011

Ok so it's not the balancer, finally got it replaced this weekend and it changed nothing. Car still has a vibration through it, that is worse from 1000-1500 RPMs and then smooths out a little, but never goes away. Checked plugs, wires, and cap all looked good. Hooked code reader up to it and ran through codes with no errors coming up. The only thing I can think of at this point is something on the transmission side, or is there something else it might be?

5litrarag · Apr 9, 2011

If it does it regardless of whether its in gear or not, its a problem on the motor itself. Look closely and see if one or both of the mounts have collapsed. You should be able to see a good amount of the dampening material sandwiched in between the mount plates. It shouldnt look like its being squeezed, just a thick piece of rubber thats about an inch thick. If the mounts look good, I guess its time to see if there is a problem on the flywheel side.