Truetrac diff oil

[villn808]

What diff oil are people using? Eaton recommends an 80w90 mineral with no friction modifiers, hard to find anything without the modifiers. Truetrac needs an amount of friction for the torque biasing to work properly.

All I can find is HD Penrite gear oil but it only comes in 20L drums.

The diff builder is recommending Penrite single weight 140 with 350mls Moreys stabiliser but I’m not sure about that.

 

[lmoengnr]

What diff oil are people using? Eaton recommends an 80w90 mineral with no friction modifiers, hard to find anything without the modifiers. Truetrac needs an amount of friction for the torque biasing to work properly.

All I can find is HD Penrite gear oil but it only comes in 20L drums.

The diff builder is recommending Penrite single weight 140 with 350mls Moreys stabiliser but I’m not sure about that.

Send Harrop a message, and ask their recommendation?

 

[villn808]

Send Harrop a message, and ask their recommendation?

They recommended Liqui Moly Hypoid GL5 85w90, they said it also contains friction modifiers but is fine.

Spoke to diff builder again and he’s adamant the 80w90 is too thin and just turns to water when hot. Going to go with what he said.

 

[mechanic]

What makes you think that the thickness of an oil indicates its lubricating quality? This is a really common misconception.

Listen to the engineers.

 

[villn808]

What makes you think that the thickness of an oil indicates its lubricating quality? This is a really common misconception.

Listen to the engineers.

Ok. So what exactly are you saying?

 

[mechanic]

I’m not sure how to say it any differently. The oil engineer or the diff manufacturer knows best.

Not saying the diff builder is wrong, but his comment about the oil being too thin is too simplistic and ill-informed. There’s a lot more to oil than how thick it is.

 

[villn808]

I’m not sure how to say it any differently. The oil engineer or the diff manufacturer knows best.

Not saying the diff builder is wrong, but his comment about the oil being too thin is too simplistic and ill-informed. There’s a lot more to oil than how thick it is.

Okay thanks, this is the advice I’m looking for.

 

[Sandman]

Listen to who ever you would be going through if it goes bang again. As if you don't take their advice there goes any liability if it turns to ****. But I agree with above, although it does factor there is more to the lubrication of parts than just their viscosity.

 

[villn808]

Listen to who ever you would be going through if it goes bang again. As if you don't take their advice there goes any liability if it turns to ****. But I agree with above, although it does factor there is more to the lubrication of parts than just their viscosity.

Now I’m confused. I don’t think either of the 2 oils is going to damage it, but I want the torque biasing to work 100% spot on.

And all the info I can find says avoid anything with friction modifiers, but builder adamant to use it, and also add the stabiliser. **** sake.

Also it didn’t blow this time, was just not built right to start with and was noisy from the start and had started to leak, 2 years old.

 

[mechanic]

The oil company will match their oil to the manufacturer's specifications. The manufacturer has done testing to determine the best oil for use.
I'd stick with those companies that publish and stand by their own recommendation. At least you can go back and tell them they made an error, and make a claim for a new/repaired diff.

Your diff builder is not liable for providing an incorrect suggestion.