Shaking
 

I just bought new Michelin X Radial Lt tires for my 97 F 150. When I get up to 60 mph the truck shakes. Ive been told that if you feel the shaking in your seat it is coming from the rear tires. Can anybody tell me what is wrong? Also the shaking wasn't there before I got the tires. I'm also going to get new shocks too.

If you just purchased the tires you need to bring them back getting them rebalanced or having the tires checked to see if one of them bad. It's the weekend get it done.

X2, it surprised the hell outta me to realize how much tire balance makes a difference. Bieng out a bit shook it like mad and when 2 were shaking a certain way, it felt like the truck was going to explode, really it was weird. The tire shop that installed them will fix this usually free for a certain amount of time. In the pants = rear tires, shaking wheel around 60 = fronts. For the hell of it, switch the tires for a bit and see for yourself the difference.

shaking
 

Well, that was the problem, they said that all the tires were out of balance. There machine wasn't working right so they put them on another one and boy can I tell the difference.