Gear lube weight?

[mrgoodwrench]

I have a dana 60 front diff with thorson locker and a 14bolt ff rear axle with detroit locker that im going to be changing gear oil in on my large heavy suburban. I have free 75-140 and 80-90. they currently both have 80w90 in them should i stick with the regular 80w90 regular or put in the run 75w140syn? I drive long distances and 4x4 with it any input welcome. Thaks mike

 

[Bent77]

Not familiar with the thorson. If it uses clutch plates, I would avoid the synthetic there. That messes with the friction modifiers
I’d sure run it in the rear though

 

[mrgoodwrench]

Not familiar with the thorson. If it uses clutch plates, I would avoid the synthetic there. That messes with the friction modifiers
I’d sure run it in the rear though

I spelled it wrong its torsen locker. its basically a detroit true track see here for more details. https://www.filthymotorsports.com/Detroit_Truetrac_p/eaton-truetrac.htm it does not use clutches.

 

[6872xtc]

I would think that the synthetic would be fine with that. I have used semi-synthetic with a couple of them, one is behind a D-max, and they work well.

 

[76zimmer]

75-140synthetic all day!

 

[6.2Blazer]

Not a huge deal one way or the other, but would probably go with the 75w-140 if I had the option for free.

 

[Babaganoosh]

I have always used 75w90 in everything.

 

[mrgoodwrench]

I have always used 75w90 in everything.

Well i have free regular 80w90 and 75w140 so im not buying anything else lol