FJC and FJ40-same fluids?

[DrUnit]

I've searched high and low and can't find an answer to this question: Can I use the same gear oil in the diffs in both a 2008 FJ Cruiser and a 1982 FJ40?

The 40 calls for SAE90 Hypoid gear oil API GL-5, and the FJC calls for Toyota Genuine Differential Gear Oil LT 75W-85 GL-5 or equivalent.

In my fruitless search, I did come across Poser's recommendation to use 80W-90 gear oil in the 40.

So, can I use 75W-85 GL-5 in both? I'd rather buy one type of oil rather than two.

 

[dgangle]

should not hurt a thing.

The 01 and 07 4Runners I have/had call for 80W-90 in the rear axles and 75W-85 in the front differentials and transfercases. I buy SAE80W-90 by the drum and run it in everything for hundreds of thousands of miles with no probs but I live in the deep south. If you are somewhere the ambient temps are very low much of the year I would use all 75W-85 in this instance.

 

[Bill McC]

I would put fluids for a modern vehicle in an FJ40, I would not put original spec fluids for a FJ40 into something new. Of course I would check things like brake fluid and coolant compatibility.

Any gear lube from today will work in an old 40. It will give you a reason to change it. Synthetic would probably be a waste in a 40 though.

Newer stuff, having all that attention to fuel efficiency and being made to much closer tolerances with correspondingly longer life expectancies, probably needs the factory spec. type of oils.

For instance: a fun little '64 Popular Mechanics book I have goes over the need for oil change intervals of 500 to 2000 miles. Over the road trucks get to go even as far as 5000-7000 miles. Oils back then were not as good, weren't filtered as well, and in the engine, suffered from more blow-by contamination.

Of course if you want to put 30wt. non-detergent motor oil in your fjcruiser, go ahead, it isn't my car.

This is of course my opinion and not necessarily substantiated by the facts.

 

[dgangle]

The last statement says it all.

the most important aspect is the API "GL" rating. see Gear oil - Wikipedia, the free encyclopedia

 

[DrUnit]

Thanks for the opinions.

I definitely wouldn't use old-school fluids in the FJC. But I'm hoping to use FJC-spec fluids in the 40 wherever possible.

So it looks like I can use 75W-85 GL-5 gear oil in the diffs in both the FJC and the 40. If anyone disagrees, chime in.

 

[bikersmurf]

You'd basically be using a 75W oil rather that an 80W. You'd probably find more difference between brands of gear lube.

I wouldn't hesitate to use it. I'd just go for it.

 

[dgangle]

There is nothing "old school" about SAE 80W90 GL5. I am telling you that you could use it in either, not have any problems and probably not be able to tell the difference. I would rather have a higher viscosity oil in things that don't call for it than to have a lover viscosity oil in something that calls for higher.

It's the same thing as someone having 2 cars with one engine calling for 5W30, the other 10W30 and using 10W30 in both.

I have not owned an FJC but am suprised that the rear diff doesn't call for 80W90 like both 4Runers I have owned.

 

[1911]

I've searched high and low and can't find an answer to this question: Can I use the same gear oil in the diffs in both a 2008 FJ Cruiser and a 1982 FJ40?

The 40 calls for SAE90 Hypoid gear oil API GL-5, and the FJC calls for Toyota Genuine Differential Gear Oil LT 75W-85 GL-5 or equivalent.

In my fruitless search, I did come across Poser's recommendation to use 80W-90 gear oil in the 40.

So, can I use 75W-85 GL-5 in both? I'd rather buy one type of oil rather than two.

I have both a 40 and an FJC myself. I buy Amsoil Severe Gear 75w-90 in 5-gallons pails and use it in every diff, transfer case, and manual tranny that I own, with excellent results.

 

[dgangle]

Out of curiostity, what weight gear lube does an FJC call for in the rear diff?

 

[1911]

Out of curiostity, what weight gear lube does an FJC call for in the rear diff?

From the FSM: SAE 90 (above -0.4 degrees F), SAE 85W-90 (below -0.4 degrees F).

 

[dgangle]

OK, same as my 4Runners.