My truck has a problem that it has had since almost new. I thought it was out of round tires/wheels but it did exactly the same thing after new wheels and tires. Of course, the dealership denied anything was wrong with the truck on several occasions as properly trained Ford technicians will do. It bounces up and down at around 38-39mph. Feels like something's out of round. It doesn't do it at any other speed. Anyboce have any insight as to what this is?

 

Could be an out of round hob, or a hub with the wheel studs installed slightly off center. You would need a dial indicator to check it.


-Jon

 

My 2000 does the same thing there is a tsb for a new driveshaft and taihousing dealer installed mine last week it took about 50% of it out but is still very aparent

 

Might be Torque Converter shudder. If it feels like it's sort of jolting back and forth/shaking that may be what it is.

 

Mine has a manual tranny. I'm just going to live with it. I'm out od warranty and the ford hacks wouldn't be able to find the problem anyway.