OK, an example of why I prefer Mobil 1 over blue marine or ordinary grease.
My samurai dumped a U joint, (as it had for the PO) and I replaced it. I replaced it every 10K mile, meanwhile the original U-Joints went on and on... (Yes I was pumping them with marine grease..)
I bought a new one (Again) took it apart and cleaned the so-called grease the factory has used. (Truly it was only a light grease to assemble them, useless **** in use...). I assembled it using the Mobile 1, and made sure the drilled cross holes that feed the grease to the bearings was also full of the Mobil 1.
I've not had to replace it since...