top up transmission with engine oil?

[mauricem]

Hi, Ive got a MF 253 tractor (perkins 3 cyl diesel) which needs a top up of transmission/hydraulic oil mainly due to a leaking seal at the PTO shaft.

I started pouring from my drum of Caltex Agri MP oil as recommended by MF but noticed a few large globules in the mix so I stopped immediately. The drum was a few years old and about 1/3 full so Im guessing it was some water in there from condensation.

Normally I'd use that as an excuse to change the transmission oil but the current oil is very clean and a full change uses about 47litres so its going to be over $300 just in oil. The amount of "contaminated" oil added was probably under 2 litres.

So my questions are

1. Would a small amount of water in the diff hydraulics casue any potential problems? If I keep it in I'll monitor it for milkiness etc.

2. As I still need to top it up and am out of STOU can I just use the same 15w40 Shell Rimula x engine oil I use in the crankcase. Its probably only about 3-4 litres needed so under 10%. As I understand it the problems with using an engine oil in the diff is mainly due to the detergents in them

thanks for any help

 

[Diamondpilot]

Hi, Ive got a MF 253 tractor (perkins 3 cyl diesel) which needs a top up of transmission/hydraulic oil mainly due to a leaking seal at the PTO shaft. I started pouring from my drum of Caltex Agri MP oil as recommended by MF but noticed a few large globules in the mix so I stopped immediately. The drum was a few years old and about 1/3 full so Im guessing it was some water in there from condensation. Normally I'd use that as an excuse to change the transmission oil but the current oil is very clean and a full change uses about 47litres so its going to be over $300 just in oil. The amount of "contaminated" oil added was probably under 2 litres. So my questions are 1. Would a small amount of water in the diff hydraulics casue any potential problems? If I keep it in I'll monitor it for milkiness etc. 2. As I still need to top it up and am out of STOU can I just use the same 15w40 Shell Rimula x engine oil I use in the crankcase. Its probably only about 3-4 litres needed so under 10%. As I understand it the problems with using an engine oil in the diff is mainly due to the detergents in them thanks for any help

Use the right oil.

Chris

 

[MHarryE]

Don't worry about detergents - good quality mobile equipment hydraulic oil has them. Many pieces of mobile equipment recommend engine oil for its superior qualities, but they come at a price. Both can handle water - in small amounts. Most can handle up to 0.1% water which is typically he amount that can be absorbed from humidity in the air - and when at operating temperature it will evaporate out. I assume you feel the globules from your bulk oil were globules of water. Think of how small 0.1% of your oil capacity is. The reason for the limit us that significant water going through the system is going to cause wear so it's best to get the water out.

 

[Oldtink]

You be the judge. Here is a good article on that subject.Can Engine Oils Replace Hydraulic Oils?

 

[LD1]

I would say to use the right oil.

Plain hydraulic systems can use about any oil provided the viscosity is correct. There is nothing special about them. Cylinders, valves, pumps, etc.

the problem is on most tractors, they hydraulics is common with the transmission. There are two things different about the transmission/rear end. 1. Very high shear loads on the gears. 2. Friction material (clutches and brakes). A "transmission hydraulic oil" takes both of those into account. I would never just use a plain ISO 32/46/68 in my transmission, therefore I would never use an plain engine oil.

Now if this were my backhoe that has a totally separate hydraulic system, or my log splitter, or a hydraulic press in the shop.....the a motor oil, ATF, plain hydraulic oil, etc will all be fine

 

[Soundguy]

If it was me, I'd top off with SOME SORT of UTF fluid vs engine oil, if I didn't have the correct oil.

As for the globs of stuff. depends.. was it emulsified oil from water.. or some heavier settled parts of the oil. If you look intot he bottom of a new un opened oil jug that has sat for a year, there is sometimes some heavy portion at the bottom.

If it was just a LITTLE moisture in there, I'd say add some transtune seafoam and then run it. In fact.. most vented sumps in transdraulic systems WILL have moisture int hem, and I'd run the transtune seafoam to help flash it off just because.

I'd skip the engine oil in favor of a real multi purpose oil.

 

[fortec]

Firstly I advise that you use the correct oil. Engine oils do not have the level of anti-wear component required for transmissions. Secondly, regarding the water it is correct, as previously stated, that the commonly recognised safe limit is 0.1% (1,000ppm), however if the oil is 'milky' the water content is well over that level. Visual appearance is not a good way to judge water content since water often does not become visible in the lubricant until about 1.0% (10,000ppm).