Motor Oil for Hydraulic fluid

[Gary Fowler]

Gary, is the 20/50 for hydraulics? If so why not use hydraulic fluid.

Ron

It is for the HST drive motors. I suppose hydraulic oil would work but the OEM calls for 20W-50 motor oil which is much thicker than standard hydraulic oil. I change it yearly along with the filters so not a lifechanging amount of money for the oil. Only 20w-50 oil Walmart has it their Tech brand of oil.

 

[dalola]

In my research on zero turn mowers, the weight oil used is usually determined by its use of or lack of external oil coolers, pumps with or without fans, and the overall capacity of the hydro system. some systems are overbuilt and some are underbuilt, some have large hydro tanks, some use smaller ones. I have had good luck using mobil 1 15w-50 in every zero turn mower ive owned. never had a hydro issue in thousands of hours usage (landscaper for 32 years). I currently own 3 hydro mowers all have mobil 1 15-50 in them and all originally came with 20w-50

Agree. My Max2 ZTR specs 20w-50 Mobil1. Has a large'ish hydro tank (4 qts), and a stack-style cooler, no fans. Never any hydro issues.

 

[DK35vince]

In my research on zero turn mowers, the weight oil used is usually determined by its use of or lack of external oil coolers, pumps with or without fans, and the overall capacity of the hydro system. some systems are overbuilt and some are underbuilt, some have large hydro tanks, some use smaller ones. I have had good luck using mobil 1 15w-50 in every zero turn mower ive owned. never had a hydro issue in thousands of hours usage (landscaper for 32 years). I currently own 3 hydro mowers all have mobil 1 15-50 in them and all originally came with 20w-50

My zero turn hydraulic system also calls for 20w-50. I've been running Mobil 1 15w-50 for years now.

 

[lzicc]

If you look in the manual, it's pretty basic. They didn't go in to detail too much throughout the whole book.

While it is possible that perhaps some additive is needed, that is in the engine oil, or there is a part is not compatible with something that is in the hydraulic oil.

Is there anything written that backs this up?

 

[ray66v]

In my research on zero turn mowers, the weight oil used is usually determined by its use of or lack of external oil coolers, pumps with or without fans, and the overall capacity of the hydro system. some systems are overbuilt and some are underbuilt, some have large hydro tanks, some use smaller ones. I have had good luck using mobil 1 15w-50 in every zero turn mower ive owned. never had a hydro issue in thousands of hours usage (landscaper for 32 years). I currently own 3 hydro mowers all have mobil 1 15-50 in them and all originally came with 20w-50

My Land Pride ZT60 uses the a hollow chassis tube frame for a reservoir, and radiative cooling. No fans to clog, or fail.

It seems to work very well. But, it is also an idea that doesn't seem to have caught on.

 

[lzicc]

I did talk to an old dealer that used to sale Thomas. They said that as long as I use a name brand oil, I should be fine. They said not to use any off name brand.

 

[MossRoad]

I did talk to an old dealer that used to sale Thomas. They said that as long as I use a name brand oil, I should be fine. They said not to use any off name brand.

Earlier you asked if you were overthinking it. My answer would be yes, you are overthinking it.

If the manual calls for 10w30, any modern 10w30 you buy at Autozone, Walmart, etc... will work just fine.

My current machine is entirely hydraulic. 4 wheel motors, three pumps, hydraulic mower deck motor, hydraulic brush cutter motor, etc.... and it's had 10 gallons of 10W40 as the hydraulic fluid from the factory since 2001. I change the hydraulic filter every 50 hours and add a quart of make-up oil at that time. Seems just as strong as the day I bought it. :thumbsup:

 

[thekkfan]

That shouldn't be an issue, and BTW found 10W30 Rotella at walmart

https://www.walmart.com/ip/Shell-Rotella-T5-10W-30-Diesel-Engine-Oil-1-gal/109014734

2x on the rotella. I'd dump it all and swap with rotella at this price ($12.79 at Rural King) if its been in there a while.