NP203 gear oil

[rcpilot]

Help.. my '76 K-5 has a part-time kit installed.. original owner does not recall what type/brand of a part-time kit he installed.. been many years.. Mile Marker kits call for 10W40 motor oil.. I want to drain and refill the T-case.. what should I use.. Thanks...

 

[Blazer79]

10W30 engine oil should be fine. Just drive it in 4wd every once in a while (not on pavement) to lube the front mechanisms.

 

[POWERMAD]

Actualy it is to get the lube to the rear output bearing.
If you don't lock it in 4loc/hi it everyonce in awile the pump never lubes the rear output shaft bearing.

 

[zakk]

i used 20w50 oil and it hasn't blown up yet/forums/images/icons/laugh.gif

 

[weisel]

I would use strait 30 weight non- detergent. But I have heard of people putting everything in them.. atf. gear oil. ect. and haven't heard about it hurting them. but i would stick with the 30 weight.

 

[rcpilot]

Thanks... I read on mile-markers web site that I should lock the hubs and drive approx. 10 miles a month to throw oil up into the rear housing.. they didn't say that I needed to actually put into 4WD though.. the original owner never did this and doesn't recall having to do it... no noises and it runs great though... again thanks