Shudder high speeds(NOT THE BRAKES) or tires

[humdiex]

Hello,

I have been trying to correct this problem for a while its driving me insane.

Getting a pretty good vibration/shudder at highway speeds sometimes a bit lower. Figured it was the brakes/rotors so I changed them both with premium parts. Seemed better around town but I took it on the highway today and while it seemed ok for the first hour or so the shudder was back.

I can really notice it on smooth pavement (obviously) and it seems like it comes in at 100% shudder then settles down to say 30% of when its bad at the good times.

I did a visual inspection and everything looks ok. I would like to think it is the wheels but they are fairly new, inflated correctly, and there are no missing weights. It had an alignment about 5 months ago.

Besides getting the wheels balanced which I dont think will work since it seems to come and go and have a very wide range of speeds where it happens. 55mph+ (90km/h+)

It is more noticeable when going down a hill with the cruise on and the engine is braking to slow it down, if that helps.

it is a 2001 Ford Taurus with 106,000km on it. New front rotors and pads, new back quick struts as well as drums/shoes ect.


What else could I check?????? Please help!

[wrenchboss26]

check tie rods, ball joints, strut mounts, and wheel bearings. also rotate the tires and see if it is better, worse, or the same. do you feel it more in the steering wheel, brake pedal, floor board, or seat?

[humdiex]

it is in the entire car and some in the steering wheel, nothing in the brake pedal now that I have new rotors and pads.

im thinking of just trying to get the wheels checked to see if they are bent (alloy rims)

[Willyum]

If those "fairly new" wheels are aftermarket, I would put the stock ones back on and see what happens.