Just got my new 2.5" driveshaft today and it came with non-greasable U-joints already installed. My question is, should I keep the non-greasable U-joints or switch them out for greasable ones? I know that solid U-joints are stronger, maintenance free, and the car came from the factory with no zerks. The car currently has greasable U-joints, and I would be getting quality greasable U-joints if I should switch.

 

Greasable U-joints are not any weaker if installed so the zerk hole is installed so that it is under compression when car is going forward. Unless you are planning on putting a 100K on them, I'd leave the non-greaseable ones on.