1995 F150 XLT 4X4 78,000 miles - Ford dealership is not able to diagnose/fix shutter - vibration that became obvious after ball joints, radius arm bushings, shocks, rotors, brakes, tires replaced. Transmission has been serviced and entire fluid replaced with Mercon 5. The shutter is intermittent (3 - 5 seconds at a time) and most obvious between 35 - 40 mph but does not change with increase or decrease in speed or with/without overdrive engaged. The frequency does not seem to change with a change in speed. They think it has something to do with the transmission but I am skeptical. The U-joints have been inspected but not replaced. Any ideas would be greatly appreciated. Thanks.

 

Does the entire truck seem to shake or does it feel like it's coming from a particular area of the truck?

 

The entire truck shakes. It always happens in the same spots on my way to and from work. It feels like you are going over rumble strips but the road surface appears to be smooth. That is why I thought it had something to do with the suspension, not the transmission.

 

Is that the only time it does it? Does it do it when you go to Grandma's house?

 

^^ ...that's cold...

 

LOL, i seriously did not mean it that way.

Let me rephrase that....

Do you have the same problem with your truck, when you are driving on roads, other than, the road to and from work?

 

If it became obvious AFTER the parts were changed, then you should check the new parts that were installed. I would be especially careful looking at the brake rotors, tires, and balancing of the tires. Any chance the drive shaft was disturbed, causing the balance to go off, or a bad u-joint?...
Just thinking out loud here.....
Good luck,
Kevin