Need urgent advise! Differential and transfer case fluid change

[paraplan]

Hi guys!

I need an urgent advise. I have 2005 T4R V8 Limited. I just changed the fluid in all 3 boxes: front, rear diffs and transfer case to synthetic Red Line MT-90 75W90 Gear Oil. I got it here Red Line MT-90 75W90 Gear Oil (1 Quart) - 50304 | FCP Euro
I just noticed that this fluid is rated as GL-4 where as the manual suggests GL-5 type fluids. I'm not sure what to do at this point, do I need to drain this fluid once again and use the correct stuff or having GL-4 is just fine?
Please help!
Big thanks in advance.

 

[ebg18t]

IIRC The difference between GL-4 & GL-5 is the friction modifiers. I am not sure I would want to run the wrong application in my diff's and transfer case long term. The TSB I bookmarked also talks about GL-5: differential GL-5.

But I am not 100% sure if running GL-4 will cause a major issue or not. Hopefully someone with more experience will chime in' so my post will bump your thread back to the top.

 

[Climb14er]

Informational comment... removed.

 

[paraplan]

I did some research on different forums and it looks like MT-90 can be used in transfer case but not in differentials. The reason is that differentials have hypoid gears where as transfer case does not. Here are some links to these discussions:

Can I run Redline MT90 in my transfer case? - YotaTech Forums

Royal Purple Max Gear 75W90 and Red Line MT-90 | ATF, Differential, Trans, Brakes, P/S | Bob Is The Oil Guy

Redline for differentials and transfer case - Toyota Nation Forum : Toyota Car and Truck Forums

Moreover, Toyota is using different OEM oils in differentials and transfer case. Here are the part numbers:

08885-02506 Differential Gear
08885-81080 Transfer Gear

It looks like 08885-81080 does not have hypoid additives in it, so I believe using MT-90 in transfer case is fine.

I'll drain MT-90 from my diffs and save it for later use in the transfer case. For now I got Castrol Syntrax Limited Slip 75w-90 Gear Oil because it was the only synthetic gear oil I could fine in local O'Reilly store. The price was $12.99, which is not too bad, very much comparable to what you can get online.

Anyway, please share your thoughts, I'd really appreciate it!

 

[gshadow325]

Something to think about with red line synthetic especially on a older vehicle. I did synthetic on my 3 boxes. A few months later it developed a leak. I suspect with the lower viscosity of the synthetic the fluid seeped pass the older worn seal.