type of oil

I agree with you..............except if any of those compartments have a pump and filter. Then I would stick to the lighter weight oils. I might instead use a light weight gear lube, but don't know how light is actually available.......maybe 75 wt??

Note......gear lube "weight" and engine oil "weight" are not on the same scale. So a SAE 50 engine oil is more like a 75W-90 gear lube I think.

Any clutch compartment/powershift transmission should have a drive train oil in it. Motor oils probaby don't offer the best performance there and gear lubes are not appropriate either.

I had the same issues. My local oil supply co explained it this way. 50wt motor oil is the same viscosity as 90wt gear oil. The difference is that motor oils have detergent in them, unless you purchase a non detergent. If the spec calls for 50wt, use that, not the non detergent.

thanks for the reply gents, i was going to go with the book on this it just seemed a little odd to put motor oil in gear compartments 30wt motor oil in a manual trans scares me but it must do the job. thanks again

I think once again we need OM's viscosity chart--I know i printed it out but can't find it---good candidate for the tech library.

Hello bullcrk,6. The transmission and bevel gear compartment also includes the steering clutches and relies on a pump and filter to operate. Cat designed the transmission to operate on the 30W motor oil. You must have been taught as I was on older machines where motor oil was for motors and gear oil was for gears. What was true then does not always remain true. I bought a new Camaro Z-28 in 1983 with a 5 speed manual transmission. I was shocked when both the dealer and the owner's manual said ATF went in that manual transmission.
There is a little wiggle room on the finals as they do not have a pump or filter.
When in doubt, rely on the manual for your machine.:cool2:
Happy 'dozing
Craig

I am finally a CAt Mechanic and all we have on the wall is 15-40 engine oil, 10wt for hydraulics, 30wt for transmissions(and some other compartments) and 50wt for finals and axles, etc. if we need 90wt we have to order it, there is a reason for that, tighter cleatances need thinner oil, this is all SAE Engine oil not Gear oil im not saying their the best but its my .02.

but there is always grey areas, like the getrag 5 speed transmission in my 1993 dodge cummins, i over fill it a quart to lube the bearings better, so therefore there is always grey areas

One more time.....

well just so happen i was at both my local cat dealer and my oil and fuel supplier today and what i got from both my go to guys was if i want to put gear oil in the finals, same as the older cats go ahead, but the trans,clutch,bevel gear compartment 30wt drivetrain oil is the way to go, not motor oil or gear oil 50wt drivetrain oil is what cat puts in finals as well. truth be known the oil companys prob make a few diff oils and just label the containers different and we don't know the difference and they laugh all the way to the bank.makes me wonder some days you keep 30wt for the old cats, 15/40 for newer ones, 15/40 synthetic for the new isx cummins motors ,synthetic gear oil for the truck drive trains regular gear oil for the rest 3 0r 4 diff wts of oils greases hydro oils you almost need a ware house just for oil storage. and we prob only need a cpl diff oils and they would work in everything.

Thanks for once again posting the chart Old Magnet. In the nineties my Cat dealer told me to start using "drive train oil". I had no failures using Series 3 30W motor oil in the bevel gear compartment as my service manual listed for all my tractors. I could not justify having two 30W oils, and feared the results of an operator accidentally adding drive train oil to a engine. I had no issues until I sold these machines in 2000.
I was told that later model machines had a different composition disk material for steering clutches and power-shift transmissions that required the "drive train oil".
I think using the motor oil as listed in the service manual is okay if the trans/steering clutches are the original design.:target:
Someone please clarify the drive train/motor oil issue. What happens if drive train oil is put in the engine?
Thanks,
Craig