What Types Of Gear Oil Used In 1967 Cj-5?

Obviously you've never owned an older British motorcycle.

 

Or a Harley.

 

Glen, I run 20-50 motor oil in my '60. Mainly because for half the year or better, the lows around here are close to the 100ºF mark on the thermometer.

 

Sorry 1960willysscj5, I owned a 97 FXDL for 15+ yrs and it never leaked a drop of oil. That was true in the old days but not for a long long time. Reputations are hard to live down.

 

I just saw on O'Reilly's shelf a gallon of GL-4 called Masterpro. Cost: $19. But it's SAE 140. My feeling is that that's far too thick. Is this true?

I've only once changed the transmission/transfer oil in 66 CJ5 and I used Staylube GL4 that I got from NAPA. I think it was 80/90 weight. But what about this low priced O'Reilly's GL4, 140 weight? Okay to use or not.

 

Again… the OEM/FSM specifies SAE 80 or SAE 90, depending on season.

You decide.
If your new car or motorcycle called for SAE 20, would you use SAE 50 because it's off-brand and "cheaper?"

 

That reminds me of growing up in western Kansas. Dad had (and still uses) a '53 Chevy to feed cattle. He always parked it aimed at the haystack. On a really cold winter morning we would start it up and leave it in neutral to let it idle to warm up. I don't know what he had in the manual tranny for gear oil but it would get so stiff sometimes the truck would creep forward in neutral until it got to the haystack.

 

I didn't find any alternative oils recommended by the oil expert I found that were substantially lower priced in the quantities I will probably need. So, I did buy 85w90 GL-4 (StaLube brand) after all and am now putting it into my xmission & xfer case.

But just for you information, the oil expert I consulted with did claim that TO-5 oil used in CAT equipment and 20w50 with either CI-4 or CJ-4 spec would give equivalent ep protection as the 85w90 GL-4. He said that old Chevy LUV and some other suv's recommended the 20w50 oil to be used for their manual transmission fluids and that those vehicles plus the CAT heavy equipment all had gears that were put under very heavy loads. To me though, it does seem that the higher viscosity 85w90 might also stick to the gears better and I would think that would also be helpful to better lubricate the gears.

I just drained the oil out of my xfer case and it was not empty like I thought it might be, so it seems that the leaks weren't as bad as I thought they were. I'll probably lose about 1 gallon of gear oil total from the power train in the next year (and much of that will be the lower cost gl-5 oil, not the high priced gl-4 oil) and by then I'll have time to put all new seals and gaskets in everywhere and hopefully stop the leaks or at least greatly minimize them.

 

I'm giving some zombie life to this dead thread, but that is some good info: The Tractor Supply link below still works and that is the first time I have seen an advertised, straight-weight SAE 90 gear oil that is the type originally specified in the FSM. Except it is GL1, and not the stated GL4.

That's the summer weight specification and if you lived in southern California or somewhere without a "real winter", that's all you'd need. Plus, that's a hefty two gallons of gear oil at a good price.

BUT... I'm going with the Sta-Lube (GL4) #SL24239 85W-90 for better all-around usability in a wider temp range.

 

Sorry to revive an old thread, but I figured it would be better than starting yet another gear oil thread. I have read a lot of them on here and am left with one burning quest. I have gathered that GL5 is not ideal since it might negatively affect the synchros in my transmission. Upon searching for GL4 I've found my options are limited. I have been able to find GL4 in 75W80, 75W90, and 85W90...just not the 80W90 that I have seen recommended. Out of those three what would be the best option? I'm no oil expert, but I gather that the main difference between these is going to be viscosity. Thanks for any help in advance!

 

I would go with 85w90, since it'll be a bit thicker when cold (maybe less marking of territory? ). They'll all be the same when up to temperature.