I was hoping you guys could help me out. My dad borrowed my truck a couple of weeks ago to go to the Kentucky Derby, and after he got back I noticed this problem. When I get going faster than 50 I feel a distinct vibration and almost a shaking. I think the front end needs to be re-aligned but I'm not sure. Any ideas? BTW, my truck is an '01 F-150 Supercrew Lariat with the 4x4 Off Road package. No aftermarket work done to it and about 13,000 miles. Thanks

 

Sounds like dad may have hit a curb. Did yo ask him about it? That would be fun... give the ole' man some crap about his driving

It sounds to me like one of two things: Front-end or tires. I would check the front tires for any bulging sidewalls or other deformaties.

 

......and it may be something as simple as your Pop whacked a bump and knocked one of the tire balance lead weights off the rim, thus promoting the high-speed shimmy. You might be able to see the outline of where the weight was. Happened to me.

 

I had a suspicion that he hit a curb or something, but I'm kind of suprised that it would affect the alignment considering that I've got the off road package. I thought it would take more than just a bumber to knock that thing out of alignment

 

No its not alignment, have the tires balanced.
Above 50 mph its balance.