[Capt. Chaos]

I know most modern-day rear wheel drive vehicles have factory-installed universal joints in their drivelines that do not have grease zerks in them.

On average, how long should those types of u-joints last before they need to be replaced?

I replaced all three u-joints on my '95 Chevy C-1500 2WD at around 80,000 miles because the rear one felt like it was dry when I un-hooked it from the differential yoke and moved it around.

My '02 GMC K-1500HD 4X4 has about 83,000 miles on it now and if I find one u-joint that's bad I will change them all, as well as install a new carrier bearing while the driveshafts are out.

[smj999smj]

There is no set time for U-joint replacement. Generally, they are good until the seals fail and water starts to get inside them. When the start making noise, cause vibration or exhibit play, then they are due for replacement. I've seen many go well over 100,000 miles without problems; I have over 200,000 miles on my truck's original U-joints, though I have replaced the carrier bearing once at approx. 150000 miles.

[ramntm]

My 1994 Silverado with 243,000 miles still has all 3 original universal joints, along with the original carrier bearing.