Lucas 85w-140 for transfer case?

I know ECGS recommends it for the difs, has anyone used it in the transfercase or is it too heavy? I got a good deal on a case.

Case not csse

 

I wouldn't. I put what toyota recommends. Will it hurt anything?........I doubt it

 

NOT a good idea! The transfer case uses an internal pump to lubricate it, with a very fine filtering screen. A higher viscosity lube would likely starve the case of proper lubrication. I would also not use any oil additives. I have seen some plug this screen. A good synthetic oil in the proper viscosity is best.

 

That's what I needed to know thanks

 

Is it actual fact or just your opinion that the higher viscosity is bad for the pump? Not trying to start anything, just curious cause I run Lucas 85W140 and I’m wondering if I absolutely need change it.

 

How long have you been running it?

 

About 20k miles.

 

All I know for a fact is that the screen is small and very fine. It is meant for a thinner oil. A thicker oil will have a harder time getting through, which means less oil. The problem is, we won't know for SURE until yours fails. If it were mine, I would change it.

 

The more I think about it the less I’m worried about it. I swapped to a FJ t-case, it was only $250. I’ll swap in another if it blows up I guess. I’ll be sure to report back if it goes to shit.

 

why would u want to use a 85w140?

 

I’m not sure now. I think I remember reading something where they did a tear down one a transfer case using

$26 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 vs 85W-140 and the heavy oil one looked better. I’m having trouble finding the thread. When I regeared I just went ahead and changed all the gear oils to 85W-140.

 

Using the same fluids in all three is what I would like to do but it's not a deal breaker I'm going to use the 85w-140 in the front and rear but still unsure on the t-case.

 

For whatever it’s worth I’m aiming to go with 85w-140 in my LSD rear on my 07 taco and stay with

$26 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 in the t-case and front diff when I change them all again at 90k. I have used 80w-90 in the rear diff up to this point, I tried 75w-90 in the rear diff once but it chattered with synthetic in it...even with extra lsd additive. Went back to conventional 80w-90 and a few oz of friction modifier, all is good.

 

I have been using 85w110 Redline in the rear diff for some time, but

$26 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 in the front. The front never sees the heat or the speed that the rear does. I don't use hypoid gear oil in my manual transmission or transfer case. I use Redline MT-90 in both. My transfer case has over 200,000 miles on it with zero issues. It's an FJ twin stick transplant.

The transfer case never sees anywhere close to the heat that the rear diff does, nor does it see the pressures generated by hypoid gears, so I see no need at all for the high viscosity oil.

 

The needs of all three are different. The 85-140 is fine in the rear. The front doesn't need it at all, and the T-case is a completely different type of gear box. It's a small expense every couple of years, and the left overs will keep till the next change. I don't want to be the voice of doom, but I see only potential downside to using 85w-140 in the T-case, no upside.

 

heavier oil can affect MPG in the diff

Heavier oil does not mean better protection

in cold climates, heavy oil can be bad or not let thins work until warmed up

 

CHALLENGE

 

Do you still use the 85w140 in the tcase? Trying to decide if I wanna stick with all the same oils

 

Yea

 

If you like to be stuck in 2wd, then go ahead. But if you like to be able to use 4wd, keep it to 90.