Improper oil in Hydro... What should I do?

[Docwheelhorse 2,682]

Hello All, I traded my C141 8 speed for a C161 Hydro and a C141 Hydro... both are good looking rides and run good. The C161 has motor oil in the transaxle and I believe so should the C141. Well the C141 has ATF (Auto Transmission Fluid) in it and I really would like to change it to 10-40.... If I drain all the ATF out and swap in the 10-40 and run it for a bit and do another full change to 10-40 will I be helping or hurting this unit? Thanks and let me know your thoughts or experiences in doing this.

Tony

[nylyon-(Admin) 7,300]

Tony, you're right they both should have oil in them, but a question for you first? Does the ATF look clean and good? Perhaps the hydro was rebuilt and ATF put in after all the parts were cleaned? Here is my 2 cents worth, I would leave the ATF for 2 reasons. First, changing to oil should be done by taking everything apart to get rid of the ATF. And second, if you plan to use the tractor in the winter, the ATF will start to work LONG before the oil equipped counterpart. Now, I'm not sure if there could be potential damage by using ATF which would be a drawback.

[Docwheelhorse 2,682]

HI--the ATF is clean and good. I don't think the transaxle was rebuilt anywhere in the near past My thoughts are that the ATF is simply to thin to run in it and I will be taking years off of the life of the pump etc.... hopefully someone can tell me if I am worried over nothing

Thanks!!

[sorekiwi 761]

My '73 14hp Auto has ATF in it, and the hydro's never been touched in 36 years (apart from changing it and the filter every couple of years...).

I'd leave it alone.

[TT-(Moderator) 1,145]

Near as I can tell, the official change from ATF to motor oil was made when the hydrogear units were "replaced" by the piston-to-piston units in mid 1973.

I see absolutely no reason why either system won't work on either type of fluid - as long as they aren't mixed.

I am tempted to give UTF (universal tractor fluid) a try in one of the Sundstrands just to see if there's any difference. We use it in all of the equipment at work - including full hydraulic drive/lift systems and hydrostatics too. It is a very light color and we actually add a red dye concentrate so leaks can be detected quickly and easily - which ultimately makes it look an awful lot like ATF.

I guess you can go by the old rule of "if it ain't broke - don't fix it", Tony. Unless/until it gives you a problem, I wouldn't be concerned.

[bo dawg 516]

I agree, I wouldn't change a thing untill there's a problem.

I done it once going from ATF to 10-30 and it just never was the same. Although I may not have goten it completely cleaned and more than likely mixed. It moved a little slower and wasn't as quick to respond.

The only thing 10-30 helped was allowing trans to run cooler. Where I used to live I had 4 acres and the back half was up grade and it always slowed down going up grade when it got hot on the ATF.

My 2 Chargers has the ATF and they operate great and very quick. I will keep them that way as long as I own them

But that's me :ychain:

[Docwheelhorse 2,682]

Thanks for all the replies.... I guess I will leave well enough alone. The 161 with the 10/40 seems a bit snappier then the 141 with the ATF... maybe the 141 just has that much more wear on it. I suppose a good test would be to run the ATF unit around for a couple hours cutting grtass and see if I end up with one of those fancy "infinite neutral..." transaxles

Thanks

Tony

[Rod(NASNUT) 1]

I am tempted to give UTF (universal tractor fluid) a try in one of the Sundstrands just to see if there's any difference.

[plowmaster 0]

ive always used utf in all of my hydro units.

[Rideawaysenior 25]

Someone at some point I think, and by thinking that means a lot these days, but I seem to recall that they may be hydraulic dampeners in the ATF fluid which would attribute to a sluggish response compared to 10w-40. I could be wrong though.