Q: How to Check and Replace CV Joint and Universal Joint?
A: Universal joints are mechanical couplings that connect two rotating components at different angles. They are composed of yokes connected by a crosspiece called a trunnion, with needle bearings in cups at each end of the trunnion for smooth torque transfer. Wear in the needle roller bearings can cause vibration, noise, and ultimately disintegration of the bearings. To check for wear, the driveshaft can be turned while holding the rear differential pinion flange or front half coupling, or a prybar can be used to test for looseness. If any wear is detected, the driveshaft should be replaced. On the other hand, the constant velocity joint on the forward end of the driveshaft is not serviceable and must be replaced if worn or damaged.