Truck shakes at high speed

[Pretzeled_in]

I have a 1993 ford ranger 2wd with a 4.0 v6 and the 4 speed automatic and on the highway it starts to shake but once it shifts into 4th gear the shaking gets way worse. My guess is something in the transmission is going bad but I've been told that it might be a suspension issued or a driveline issue. Has anyone else experienced something like this and what might be the solution? id rather not have to take the whole truck apart.

 

[rusty ol ranger]

Sure the shaking get worse in 4th or is it just the speed where its shifting to 4th?

Try running it up to the bad shake speed in 3rd and see if it shakes just as bad.

"Shaking" is normallt something like a bad/out of balance tire, bent rim, something like thst....might wanna check your lug nuts too.

"Vibration" is usually driveline related.

 

[Shran]

Common Ranger problem areas -

ball joints/wheel bearings/tie rod ends in the front - any movement in the front end can cause something like this, more common on 4x4 trucks
u-joints - especially if you have an extended cab with a 2 piece driveshaft! I just fixed one that had two bad joints and that took out the carrier bearing too. BAD shaking over 15mph

Tires out of balance or with a broken belt will shake at weird times/speeds

Probably not your transmission, that's the last thing I'd suspect.