bad shake on '91 SR5 x-cab 4wd pu

[celchlepp]

Hey all, I have a bummer of a problem with my truck right now. as a rookie on this site, I don't know if my truck details show on the forum automatically or not, so my little truck is a 1991 SR-5 V-6 4wd Manual shift. the problem is there is a pretty bad vibration going on that you can feel throughout the entire truck. not window rattling, but mirror vibrating enough to render the mirrors useless - ALL BUT THE PASSENGER SIDE MIRROR. mind you, the mirrors are NOT the concern here, but perhaps a clue.



last saturday I replaced the carrier bearing with high hopes that that would fix the vibrations. nope. next suspicion is the U-Joints - all four of them? it ONLY vibrates on acceleration, and no other time, so it isn't a bent wheel, or a lost wheel weight, or anything else having anything to do with anything EXCEPT the drivetrain. it is also not RPM related. and is NOT speed related either.



with all of those basic factors eliminated thus far, I am in desperate need for some advice/input/recommendations/suggestions as to what to do next. please let me know of I need to spend next saturday with the drivetrain (excluding the very frontmost shaft for 4wd?) replacing U-Joints.



And since it has been a few years since I’ve messed around with U-Joints, I intend to follow the “guide” found at http://www.pirate4x4.com/tech/ujoint_install/ unless you folks have a better chunk of advice for me to adhere to at this time. Will a bad U-Joint make the whole truck vibrate a good bit? I was really hoping it was the carrier bearing, but as mentioned, it wasn’t. L



Thanks. I am planning on working on it this Saturday, so replies before then would be most helpful!

Chuck

[burger]

you can check the u-joints by getting under your truck and checking for play.grb the driveshafts on either side of the joint 'an give them a good twist back and forth.have truck in neutral for this.the only other thing i can think of might be the clutch...