Vibration

I have a '97 4cyl. 4 speed S10PU. When shifting into 3rd gear and accelerating past 35mph a noticeable vibration occurs to the vehicle. The vibration continues at all speeds above 35mph. The vibration seems to lessen or dissappear when I lift off the accelerator pedal or push in the clutch. Any ideas as to what the problem is?

You might wanna check for seized or loose universal joints,a broken rear (transmission mount) or if it's got a center hanger bearing it may be going.

To check for loose u-jionts,place the truck in neutral,apply the emergancy brake,and as a safety measure block the wheels.

Grasp the front yoke where it goes into the back of the transmission,with one hand,and the driveshaft with the other hand and twist back and forth and up and down.It should n ot have any play at all.Do the same with the rear one.

For seizes u-joints you will have to remove the drive shaft and rotate the joints through their range of motion.they should move freely with no resrictions or binding.

For the rear mount use a large screwdriver or pry bar and see if the rear of the transmission moves up.

surfacerider

Start off simple, get your tires balanced and rotated.