I was wondering if a 10-30 TO4 oil could help prevent slipping in some gears over using a straight 10 weight oil? Also can oil that may need to be changed cause slipping? My track loader calls for 30W but the shop said 10-30 would work better for different temps. The grader with an 8400 transmission calls for 10W. Originally called for ATF but they discovered fairly soon that ATF caused slipping when warm. They also had improved clutch plates for the trans. I know the oil and filter has been changed since new. Probably several times. Not sure if the trans. has ever been worked on but a couple bolts are missing for the trans. guard so I'd guess it has some work done to it. Mostly wondering how much difference new or different oil could make? Is synthetic any advantage in an older transmission?
I use 15-40 for summer. If I’m gonna use it a lot in the winter i use trans hyd tractor fluid. If it’s slipping I’m skeptical heavy oil will fix it. Shortly after Champion came out with the 8400 there was a recall Orings in the clutches were changed to help with the clutch slipping.
15-40 engine oil in the transmission? Never heard of 15-40 TO4 type tranny fluid.
Is it a consistent issue or something that happens during start up, after it gets warm, etc? I don't think oil would solve a slipping issue in those transmissions long term, You could try running the 30w oil and see what it does. I've always been in the school of Synthetic is for new stuff and once you start running it you don't deviate, and running it in older high hour stuff is more prone to leak's and whatnot, but maybe thats all changed at this point.
The grader was at full operating temp. when it happened. Maybe I should have just downshifted more??
Yeah modern ATF is technically about 3.5 to 5wt fluid, THF might help with clutch loads and help deglaze the steels if you have been slipping. Going up to the TO4 spec fluid wouldn't hurt anything. Like any transmission heat is the enemy... I tend to like to rev the engine more than lug them in these graders just because the transmissions in these machines are not real "stout" like you would think. More RPMs means more torque multiplication, more fluid pressure/volume and cooling ability.
Worn out trans oil will def cause slipping, when it loses its shear strength and viscosity improvers / friction additives (which all break down with use and heat cycles) it just loses its ability to hold the clutches
I remember reading it's important to change trans. fluid and the filter at recommended intervals. My grader being an 86 may have been early enough to come with ATF from the factory (apparently caused slipping) but it mentions in the manual it should be changed 10W trans. fluid. I topped the fluid up a little but should just drain it and replace with new. I'm sure it has been changed because it has a NAPA filter but who knows how many hours ago and exactly what fluid was used. Maybe mixing with the top off oil contributed to the slipping?? AFD Petroleum as well as a new Petro Canada lubricants facility are both 10 minutes from me and have TO4 spec oil. The Petro Canada might only be a wholesale warehouse but I bought the top off oil at AFD. If I recall it was about $127/barrel which I thought wasn't too bad at the time. Who knows how much it has gone up now. Would be nice if a fluid change improves the issue.