I had the universal joints replaced on my 1999 Ford Ranger now it vibrates badly starting at 45 mph and when I coast at 65 mph the vibration is very significant. The mechanic does not know what is causing this. I never had this problem before changing the U-Joints and I have 171,000 miles on the truck.
If the vibration started after replacing the U-joints, then one of the U-joints was installed incorrectly.
It is probable that the driveshaft was not installed correctly after the U-Joints are replaced. If the driveshaft is turned 180 degrees from where it should be, it’ll shake like crazy as you get faster. I’ve done this myself, and had the same problem.
The problem is NOT that the driveshaft is on backwards end-for-end, but rather that the shaft is turned on either the transmission or rear axle flange connection. (Or both!) The service manual warns to make marks on the driveshaft connections to ensure that it is lined up properly when it is reinstalled, to preserve the balance.
It is also possible that the bracket was installed 180 degrees off when the new U-joint was installed. The symptoms are the same, but you can usually fix this one by the same method as above.
Hope this helps!
Jesse this thread is 5 months old. They have solved their problem by now or gave up.
Let’s also close this old thread, please