Vibration at high speed

[animale]

I am very familiar with Lincoln vehicles from years of experience with running a Limo service. I just bought my first used car for some fun a 98 Lincoln Mark VIII in real good shape. After looking at several of these all of them had the same problem at speeds above 60 to 80. There is a good vabration in the entire car. It seems to be the same problem accross the board with all of these models. The rear view mirror shakes so much you cannot see any details behind you. I put some performance tires and lined up the front end. We did not find any bad or loose parts. We also looked at the drivshaft and did not see any problems.

Does anyone know if this is a common problem with these models? I have not gone thru the tranny yet. I have driven it for over 2K miles and the problem has remained consistant, not worse.

Any ideas please forward.

Thanks for your assistance in advance.

[el lobo]

I would check for a bent wheel and also the rotors.

[animale]

I would think a bent rim would be picked up during several high speed balancing. When I put the new tires on I thought it was one of them so we had them balanced several times. I am changing the rotors out soon with some slotted ones, so we will see what that will do.

I think this is one of those needle in a haystack problems. Unless somebody has seen this problem before with these models.

Thanks again

[ONEBADMK8]

It's the 2 piece driveshaft vibration issues that plague these cars. You need to get a Metal Matrix carbon composite shaft from:

http://www.dennysdriveshaft.com

It's the holy grail of this issue, trust me we have been hot rodding Mark VIII's nearly since their inception and we have done it all to alliviate the vibes and this is the ONLY cure.

[turn_on68]

I just noticed this same problem after putting on the Michlein aqua tread tires.Mine is at 80 and above and since I normally don't drive at that speed because of the smokies it doesn't bother me.

[paul_meets_mark]

I have the exact same problem, but im sure mine is because my tie rod on the ps is very loose. If you didnt check that, try it. I just jacked mine up and grabbed the tire and wiggled it back and forth, I could feel a lot of play, my buddy had the same problem on his 97 LSC.
If you havent already, give it a shot.

~Paul_meets_Mark

[Crasen]

Man I sure hope he hasn't been driving this long with a bad tie rod end. That post was like two years ago, lol