Gear Oil Question

drjay9051 · May 3, 2014

Time for the 50 hour on my DK40HST. Not clear on front axle gear oil.

Manual calls for "SAE 90 gear oil or better, or same as T/M oil."

Two questions

By T/M are they referring to transmission? In other words I could use hydraulic fluid?

Secondly i found both 80W 90 and 85W 140. So is 85W 140 "better than" 80W 90? May be a bit thick for north Florida.

Any help is appreciated.

Soundguy · May 3, 2014

if your manual is specing 80 or 90w fear oil.. then 80w90 should be fine.

PS. most tractors do not use plain hyd oil in their transmission.. but rather a multi purpose universal oil. UTF fluid etc..

drjay9051 · May 3, 2014

Soundguy said:
if your manual is specing 80 or 90w fear oil.. then 80w90 should be fine.

PS. most tractors do not use plain hyd oil in their transmission.. but rather a multi purpose universal oil. UTF fluid etc..

I was referring to tractor trans/hydraulic not straight hydraulic.

Any clue what "... same as T/M oil." is referring to??

Soundguy · May 3, 2014

not familiar with your machine or specs so I wouldn't even hazard a guess as to what they are refering to.. that's why I'd stick to what they said previously.. IE. if they called out a gear oil spec.. at leas tthat you know you can dupe.. etc..

dennis52 · May 3, 2014

I believe MT indicates that it is safe with softer metals
80/90 is ok

drjay9051 said:
Time for the 50 hour on my DK40HST. Not clear on front axle gear oil.

Manual calls for "SAE 90 gear oil or better, or same as T/M oil."

Two questions

By T/M are they referring to transmission? In other words I could use hydraulic fluid?

Secondly i found both 80W 90 and 85W 140. So is 85W 140 "better than" 80W 90? May be a bit thick for north Florida.

Any help is appreciated.

Soundguy · May 3, 2014

dennis52 said:
I believe MT indicates that it is safe with softer metals
80/90 is ok

MT1 is the rating for the safe/yellow metals..

northcreek2624 · May 3, 2014

My DK40 came with hydraulic oil (tractor fluid) in the front diff. My manual also stated gear oil, so I contacted the factory and they said that I can use either. I went with the hyd. oil to simplify things plus I hate working with and smelling gear oil. This was ten years ago and my front diff has never been apart...Mike.

drjay9051 · May 3, 2014

northcreek2624 said:
My DK40 came with hydraulic oil (tractor fluid) in the front diff. My manual also stated gear oil, so I contacted the factory and they said that I can use either. I went with the hyd. oil to simplify things plus I hate working with and smelling gear oil. This was ten years ago and my front diff has never been apart...Mike.

thanks for info.
I'm thinking the T/M refers to transmission.

Hill Billy Bob · May 9, 2014

This chart should clear things up for you. I use Traveller Premium UTF, found at all TSC stores....HB Bob

View attachment Lubricants-Chart-2012-07-20.pdf

o2batsea · May 9, 2014

Multi viscosity oils are rated by their SAE weight at cold and at operating temperature. So an 85w 140 acts like an 85 weight in the cold, and when it gets hot it behaves like a 140.
You can use good old straight 90w in the front axle. I find it easiest to fill the axle by taking off the cap on the pivot housing (doesn't matter which side) and pouring it in.
Another trick is to get a pesticide sprayer and fill it with gear oil. You cut the spray end off the wand. After you pump it up, you stick the business end in the fill hole and pull the trigger. It often takes a long time, so you should plan to put a pan under the fill, wire the trigger open and come back every few minutes to pump it and check the level.