first, my 4x4 rattles, bangs, and clanks pretty bad when engaged. any good ideas what this could be? got 155k on it and i just bought it recently.

i plan on changing the oil in both axles and the transfer case and grease the snot out of things to see if it helps any. my main question is the manual tells me to use 75W-90 in the chrysler 9 1/4 rear axle and SAE90 in the dana front. do i HAVE to use straight 90 in the front, or could i get by with 75/90 in both?

thanks

 

are you absolutely sure about the front end? If so, use what it recommends, unless theres some decent proof OTHER than someone elses' opinion to use something else otherwise. I made the mistake on a Jeep and it cost me dearly.............. I think the 75-140 is great though. Makes no sense i know, but whatever.......I need the model number, and i can get a check-chart off the computer at work and give you a 100% answer by 10:00 CST tomorrow. If your interested by then PM me. Goodnight! Its beer thirty!!

 

oil weight is not too important, as long as you stay close, i wouldnt hesitate to use a muti-grade in the diffs. its how the viscosity reacts to heat, ull be fine. the thing you want to watch out for is making sure to use a friction modifier if you have an LSD, that is a MUST. i use 75-90 in my Dana 60s, no problems.

 

I heard ky was good. Never used it though.

 

try it, it might make you go faster.