Stupid fluids Question Alert! (1 Viewer)

[Brentbba]

Ok - don't know the difference.

FSM says for Transfer Oil - API Gl-4 or Gl-5 SAE 75W-90
FSM says for Differential Oil - API GL-5 Hypoid Gear Oil SAE 90W

Was just at Pep Boys and only saw both regular and synthetic gear oil in various weights.

What's the difference between the Transfer Oil and Differential Oil? End of stupid question. :shotts:

 

[DuManchu]

Nothing that I know of. I believe the diffs just take 80W-90 GL-5 Hypoid. I used Valvoline 80W-90 GL-5 Hypoid (it says hypoid on the back) dino gear oil for the diffs, and some cheapo GL-5 80W-90 for the xfer case. The reason I used cheapo is because I need to run some gear oil through it and change it again to clean out the ATF that Jiffy Lube put in it.

 

[Hayes]

As near as I can tell, they're both "gear oil."
The FSM specs a single weight for the diffs and a multi-viscosity one for the t-case. I am also under the impression that all 80w-90 GL-5 gear oil is "hypoid" gear oil.

Most folks here (me included) just use 80w-90 in all three: front diff, rear diff, and t-case.

Hayes

 

[Brentbba]

Thanks - any recommendations from the board?

 

[OGBeno]

Coastal 80w90 dino (cheap crap) in all three, changed every oil change (or before/after wheeling trips).


-o-

 

[LX_TREME]

M1 in all three

 

[Cruiserdrew]

For the transfer-Mobil1 75w-90. I'm going on year 8 with a yearly change regardless of mileage. So far-perfect service.

For the diffs-any name brand 80w-90. My current favorite is Chevron DeloGear ESI 80w-90. You can also run the Mobil1 in the diffs, but then you'll be less likely to change it if you run in axle deep water. The Delogear is supposed to be the best of the non-synthetics.

Do yourself a favor and buy your gear oil in 5 gallon buckets and get a bucket pump. It is much easier.

 

[Cruiserdrew]

Coastal 80w90 dino (cheap crap) in all three, changed every oil change (or before/after wheeling trips).


-o-

I run the Coastal in my FJ40, and change frequently. It's cheap and gives good service. It has a very strong smell though, so don't spill it inside or you will be sorry.

 

[e9999]

yup, got a 5gal bucket of cheap Mag1 Dino at Kragen that I'll use for cleaning up the insides and that won't feel bad about dumping everytime I'll cross deepish water.

 

[7P's]

For the transfer-Mobil1 75w-90. I'm going on year 8 with a yearly change regardless of mileage. So far-perfect service.
For the diffs-any name brand 80w-90. My current favorite is Chevron DeloGear ESI 80w-90. You can also run the Mobil1 in the diffs, but then you'll be less likely to change it if you run in axle deep water. The Delogear is supposed to be the best of the non-synthetics./quote]


But then again, if you take in a little water the full synthetic will provide a big edge in lubrication over dino until you can change it out. I run full synthetics (75w-90 Amsoil) in all three and change out every two years or so and never experienced any type of problem. I run the full synthetic in the diffs as the ARB's deserve it.

 

[FirstToy]

I did the same thing as Andy, M1 in the t-case and regular cheap stuff in the diffs. I plan on changing the diffs after every long offroad trip/deep water so I thought unnecessary to spend more $. Plus the 80's diffs are a snap to get to and change.

With ARB lockers, add a bottle of GM LSD fluid along with your diff oil to keep the locker in good shape

 

[cary]

GL-4 oil is designed for gearboxes that use straight cut gears. GL-5 is designed for diffs and has extra additives to keep the oil from shearing from the angle cut gears and to handle the higher loads. You don't want to run GL-5 in a GL-4 application because the sulfur in most GL-5 oils will eat up the syncros in a gearbox. You don't want to use GL-4 in a GL-5 application because it won't provide adequate protection.


For the LC, just use GL-5 for the axles and transfer case.