Report- 75W90 Gear Oil in Tractro Trans

[Jim Allen]

For general interest, I wanted to update my Oct. '09 post about filling the trans of my Ford 2810 tractor with a mix of Amsoil and RP 75W90 GL5 syn gear oil. I've been using the tractor through this WINTER (caps because it's been a cold one) for snow removal and that's where I previously had some trouble shifting.

Good Initial Results

The original '80s-era Ford spec was for the equivalent of a 85 grade gear oil/40 grade engine oil... a "Universal Tractor Fluid" (UTF) which could be used in engines and gearboxes and was popular in those days. The stuff that was in there (likely NOT UTF) seemed very thin and I suspect it was THF installed at the dealer some years back during a repair. The bottom line was that the tractor shifted poorly (in the context of a crash box) whether hot or cold. Espcially cold (a surprise since the THF is a 20 grade).

In a nutshell, hot or cold, the trans is now shifting GREAT! Light years better than before! Even the first shift of a zero degree F start is nice and smooth. Barely more difficult than on warmer days. The Amsoil and RP appear to be playing nicely and this turned out to be a great way to use up some old gear oil stock.

 

[Turk]

 

[daman]

I see allot of guy's from other tractor forums are running the UHF in the trans(gears)and rear ends,actually thats what ford specs now in allot of the older ford tractors, like my 4500 they say to use that over the 80w90 gear oil.

 

[Jim Allen]

That's true with a lot of tractors, where the "UHF" (I call it THF, Trans Hydraulic Fluid) is contained in a centralized sump. The hydraulics, trans, final drive, power steering etc. all share this oil.

On my old 10-Series Ford, however, the trans is completely separate from the final drive and hydraulics. The PS is separate from the other two systems too.

If I had been smart, I'd have saved a sample of the old oil to test and see what it was (thought about it but was too cheap ( : < ). As I said before, I suspected it was either a THF or UHF. All I know now is that it shifted like [censored] on that old oil and it's as slick as oiled spaghetti now!

 

[daman]

But then theres arguments over using that thin UTF vs gear oil saying the manufacture tolerances haven't changed and one should use GL,both mine are separate sumps each there own the UTF is suppose to be a GL spec'd oil also,so dunno i changed mine out this fall and used the UTF because mine has wet brakes supposedly,the tractor is basically retired so it doesn't see any heavy hard work just some puttering around that i use it for at my own property,maybe i should have used a gear oil but i guess the main thing is to keep it changed.

 

[Jim Allen]

Well, I considered UTF too, as I had an unopened jug of HyTran. I really needed to find a home for the long-in-the-tooth Amsoil Series 2000 and some of my vast supply of RP Max Gear 75W90. The tractor seemed the safest venue for such an "unholy" mix ( : < )! I wouldn't argue very hard against the THF, as it works fine in my Farmall. I'm just glad my experiment was a success in the winter venue... and boy have I had to use that tractor this winter! Wasn't too worried about summer.

 

[daman]

Ahh yea,we haven't had hardly any snow here in MI,very strange year.