Recomended Gear lube for this app?

[Toy4x4runner]

ok, what would you guys recomend for gear lube on theses axles? They're under my 4runner which has 35" Mt tires, metal bumpers, custom lift used for daily driving, highway driving, rocks, mud etc.

- Rear toyota V6 axle. 5.29 gears, Full Detroit Locker.

- front axle: GM dana 44. 5.29 gears, Full detroit locker. has manual hubs, only used in slow speeds (under 20mph) and off road.

 

[1040 WreckerMan]

Thicker is better in gear oils, IMO. I would use a 75w140. For a conventional oil, Chevron ESI is a good oil and is one of, if not the only, conventional that meets Eaton's 750K mile drain intervals. For synthetic there are also quite a few good choices like Specialty Formulations, RedLine, etc.

If this were mine (and leaked like my jeep) I'd use whatever 75w140 was on sale and I usually drain my diffs yearly on the sever duty stuff.

 

[Toy4x4runner]

well my diffs don't leak (it's not a jeep lol, j/p).. I have Redlines syn heavy shock oil in the rear and cheapi 80/90 upfront. I guess I might just keep running the Syn Redline in the rear. One thing just hit me.... if my diff doesn't heat up... i'm only using the first number viscosity right? b/c i use 4x4 in crawl mode basically. rocks, slow trails etc. Nothing fast at all or long periods. I unlock the hubs everytime I hit the pavement. so is there any point to using the 140 in the front diff?

 

[1040 WreckerMan]

Well without a temp gauge it's hard to say what the oil is doing. My jeep has 5.38's and the terra low 3.15 low range in the transfer case, so I'm putting a lot of torque to both axles and they do get hot even at low speeds. It probably isn't necessary to have 140 in the front diff, but it won't hurt either. And I run 140 in all my diffs so it cuts down on the inventory.

Even at low speeds the loads on the R&P are quite high in most 4x4's so they get hot. Not to mention the ambient temp is going to start off warm being in Florida.

Using data from RL and a viscosity extrapolator, at 26.6C (80F) this oil is approximately 329 Cst, and 180 Cst at 40C. So the 140 is quite thick even at "lower" temps which is a benefit for a gear set that is shock loaded such as in a 4x4 application. A 90wt would probably be just fine, but I like thicker gear oils as I think they afford more protection in most cases.

 

[Toy4x4runner]

Bingo. sounds good. 80-140 it is. Any recomendations on cheapie brands? Coastal? I think we sell "accel" cheap gear lube at work.