Sta-lube Gl-4 140wt

My 1970 CJ-5 leaks the 85-90 wt oil and overfills my transfer case and leaves a nice puddle on the floor. Since I only drive it in the summer what's your opinion on going to the GL-4, 140 wt. Or mixing a little John Deere corn oil in with the 90wt oil ? Will it cut down the leaking ? Summertime use only!

 

Oil normally transfers between the transmission and transfer case. This raises the level in the transfer case. You can't do anything about that.

There must be dozens of threads here about sealing leaks in the Dana 18. site:earlycj5.com Dana 18 transfer case leaks - Google Search

Kinda suspect thickening the oil won't do much to slow the leaks. Better to go through these threads and try to seal it up better.

 

drip pan or cardboard under jeep
till you find time to reseal everything

 

good way to starve the components for proper lubrication. The thicker lube cannot get into the passageways to properly lubricate everything. Fix the leaks.

 

I agree. I would be concerned with the intermediate shaft roller bearings being starved due to the lack of oil flow as well as the thicker oil backflowing into the transmission, possibly starving the countershaft bearings and causing shifting issues.

Fixing the leaks may be a simple thing, depending on where they are. Output shaft and shim pack leaks can be done externally. You may also check the t case mounting bolts. Many times they can come loose, allowing the gasket to weep.

 

Thanks guys. I've read a lot on this blog and will put the oil pan under until I make time to locate the leaks and seal. Until then it's Sta-Lube 85-90.