Front Axle Lube? TC33DA&Others?

[jbman45]

Strange situation, maybe others have seen it. Went to change my front axle lube....checked the shop manual and it says to use AW Hyd, NH 134..same stuff as in the full rear sump on a hydrostatic system. Seems strange since it's an axle but called dealer, said yup....

So I start to change it and guess what....gear oil comes out, I can tell since I worked in that business for 30+ years and know what it smells and looks like. So there was gear oil in the front axle which is what I would have thought to be right anyway.

What do you guys use, or has someone found out the recommendation for aw hyd oil was just a simplification of the manufacturer but it needs gear oil?? Gear oil should not do damage, rather add better protection, any thoughts...

 

[jinman]

Don't over-think this. If you had gear oil in your front axle, somebody put the wrong stuff in there. I've noticed that the oil is very dark, but that's because the Multi-G 134 in the front axle and drop boxes has no filter like the hydraulic reservoir. Gear oil is not recommended. It is much too high in viscosity and will cause additional heat build-up due to higher friction and reduced flow.

 

[jbman45]

Yeah, you're on the right track; use what's recommended I guess! That's what will go back in at this point, was concerned a bit since in hot TX climate and we don't need too light of lubes on anything down here, may as well be the Sahara with the drought as well.

 

[RickB]

Strange situation, maybe others have seen it. Went to change my front axle lube....checked the shop manual and it says to use AW Hyd, NH 134..same stuff as in the full rear sump on a hydrostatic system. Seems strange since it's an axle but called dealer, said yup....

So I start to change it and guess what....gear oil comes out, I can tell since I worked in that business for 30+ years and know what it smells and looks like. So there was gear oil in the front axle which is what I would have thought to be right anyway.

What do you guys use, or has someone found out the recommendation for aw hyd oil was just a simplification of the manufacturer but it needs gear oil?? Gear oil should not do damage, rather add better protection, any thoughts...

Even if you have 30 years experience get just a little more right now. Don't call NH 134D oil the same stuff as AW hydraulic oil. AW oils never have met the MC134D spec, and never will. Like jim says, somebody somewhere along the line put gear oil in that front axle. It was certainly not the factory fill.

 

[jbman45]

Very good point. The 134 is far better than a typical AW hyd oil, it is really a univ tractor fluid which is far better and has a different set of additives than a simple aw fluid. The gear oil that came out was definitely a sulfurized isobutylene product and bothered me, but you all are right, especially since you use the factory spec'd oil. I was just wondering if someone found a better solution but the right oil is the 134 or equivalent rather than a gear oil. Sometimes we overthink stuff and best to go with what's designed. Guess I was just reading that section on simply filling your crankcase too fast can crash your engine! What's that all about and what a design flaw that is! Thought I should rethink the axle...but you guys are Thanks for your input...