Highway Vibe

[1stgenxsport]

I get a real annoying vibration between 70-80MPH. I have a knock off brand tires (Lemans A/T) on my X Sport, but they look great and have an excellent tread on them. I had them high speed balanced but I still get the vibe. Up to 70MPH and beyond 80MPH the vibration is not there. Is it the tires or is there some other problem?

 

[Creager]

i dont know, this problem has been discussed many times with no real definate answer.

personally i think it has to do with the limitations of the Dana 35... it is 4wd right? i think the wheel bearings and the spindle cant handle the frequency of the pressure at those speeds, which would explain why it goes away at 80 mph.. the frequency changes

god i dont know waht im talking about haha

 

[Interstate]

Has anyone balanced the brake rotors to fix this? I heard that high speed vibration even after tre balancing can be fixed by this...

 

[Albino 94LTD]

I've done just about everything;
Tires
Rims
Bearings, front and rear
Rotors
Drums
U Joints
Shocks
Removed harmonic dampener discs, one at a time and together (they are off right now)
RA bushings
Alignment

The most improvement was adding some leftover pieces from a poly bushing kit into the tranny mount.

Also check these threads;
http://www.explorerforum.com/forums...ad.php?t=118055
http://www.explorerforum.com/forums/showthread.php?t=121444

 

[Interstate]

Is it a hollow thumping noise or actual shaking? I've actually got some sourt of hollow bump/thump noise below 50, and a slight similarity at 80.

 

[Albino 94LTD]

Is it a hollow thumping noise or actual shaking? I've actually got some sourt of hollow bump/thump noise below 50, and a slight similarity at 80.

The vibration I chase is common to first gen X's. Many believe there is a design flaw between the drive train and the frame geometry. At a certian speed (not RPM dependant and it changes with tire size), the drive train sets up a harmonic vibration in the frame rails. It's like an unbalanced tire but feels like it's coming from the center of the vehicle.

I'm not sure how many sport's had it, I thought it was more specific to the 4door X's

 

[Interstate]

Is there a fix for it? Or something to make it less noticeable?

 

[Albino 94LTD]

No one, not even Ford, have found the definitive 'fix', other than to stop making that design.

Re balancing the tires is probably the cheapest thing to do first, then an alignment. The tranny mount for mine was less than $50 and I had the poly pieces laying around, but I spent a LOT of money on the other stuff first. I would recommend trying the tranny mount early in your quest.

 

[1stgenxsport]

It's good to know (I think) that I am not the only one having this problem. It's not a hollow sound but it's a actual shaking. Not violent shaking but annoying never the less. I'll check into some of the suggestions that you guys posted, but if it gets too complicated I will just coast at 85-90MPH