Help with fluids. F&R diffs, Man trans, transfer case

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I planning on doing some fluid changes on the truck this week and wanted to make sure Im ordering the right stuff.

5speed transmission: Redline MT90 2.3 Quarts
Transfer case: Redline MT90 1.1 Quarts
Front Diff: Redline 75w90 1.2 Quarts
Rear Diff: Redline 75w90 2.6 Quarts, This is where it gets alittle confusing, I've also read that the rear diff should take 80w90. I'm running 75w90 in there now with zero problems should I continue to do so?

All together 4 quarts of MT90 and 4 quarts of 75w90, am I missing anything? Thanks for the help.
 
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Thanks for the help AZTOY. Ordered everything from amazon, that manual will be useful when it comes time to fill everything.
 
Just curious, where did you hear that the transfer case should use MT-90? This is the first I've heard of someone putting MT-90 in there. I've always seen the same 75w-90 recommended for the transfer case.

I'll also be doing the fluids soon on all of the things you're doing. I ordered six quarts of Redline 75w-90 NS and three of the MT-90. Everyone seems to agree that it's not a big deal to run the 75w-90 in the rear, so I wouldn't worry about that.

Also, here's a link that has part #'s for all the crush washers/gaskets:
http://www.top4runners.com/ja/synthetic.html
 
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Just curious, where did you hear that the transfer case should use MT-90? This is the first I've heard of someone putting MT-90 in there. I've always seen the same 75w-90 recommended for the transfer case.

I'll also be doing the fluids soon on all of the things you're doing. I ordered six quarts of Redline 75w-90 NS and three of the MT-90. Everyone seems to agree that it's not a big deal to run the 75w-90 in the rear, so I wouldn't worry about that.

Also, here's a link that has part #'s for all the crush washers/gaskets:
Synthetic Fluids Toyota 4Runner Information

Honestly I think I read it on the forum about MT-90 in the transfer case, but I've been doing so much reading on fluids that maybe I miss read something. I do know that in the manual for the 5speed and transfer case is recommends API GL-4 or GL-5.

Based on the manual suggesting of the same type of fluid for both the transmission and transfer case, and everyone recommending MT-90,(and feeling sure I read that it would be ok, gotta look through my browser history). I feel comfortable using MT90 in my transfer case.

If anyone has advise against it I'm all ears.
 
This is from the manual. The recommendation for fluid is the same for 5speed and transfer case, which to me means it would be OK to use MT-90 in both.? (sorry for the huge pic)
 

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Honestly I think I read it on the forum about MT-90 in the transfer case, but I've been doing so much reading on fluids that maybe I miss read something. I do know that in the manual for the 5speed and transfer case is recommends API GL-4 or GL-5.

Based on the manual suggesting of the same type of fluid for both the transmission and transfer case, and everyone recommending MT-90,(and feeling sure I read that it would be ok, gotta look through my browser history). I feel comfortable using MT90 in my transfer case.

If anyone has advise against it I'm all ears.

Well I'm certainly not knowledgeable enough on the subject to be able to say if it will work well or not, but maybe someone that is can chime in here.

It seems like it would work, since, as you stated already, the manual calls for GL-4 or 5 in the transfer case, and MT-90 is a GL-4 oil. I think the real question is, would it be the best choice for it? Everything I've read on here has recommended 75w-90 for the diffs and transfer case, which definitely isn't to say that MT-90 hasn't been recommended on here before, I just haven't seen it.

Here's my recent thread on the same topic: http://www.toyota-4runner.org/3rd-gen-t4rs/135947-diffs-transfer-case-fluids.html
 
MT-90 is GL-4. People prefer it over GL-5 in the transmission because they are afraid sulfur additives in GL-5 can attack yellow metals used in synchronizers, despite Toyota's approval for its use. I share this fear. But otherwise, GL-5 is the superior lubricant especially for diffs. So using MT-90 in the TC is fine, but a GL-5 might be better and there is no reason not to.

I use MT-90 in the trans, but I use a cheap synthetic GL-5 everywhere else. I'd rather change it more frequently and use something more economical in those boxes. Redline ain't cheap and I don't think diffs are that picky.
 
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MT-90 is GL-4. People prefer it over GL-5 in the transmission because they are afraid sulfur additives in GL-5 can attack yellow metals used in synchronizers, despite Toyota's approval for its use. I share this fear. But otherwise, GL-5 is the superior lubricant especially for diffs. So using MT-90 in the TC is fine, but a GL-5 might be better and there is no reason not to.

I use MT-90 in the trans, but I use a cheap synthetic GL-5 everywhere else. I'd rather change it more frequently and use something more economical in those boxes. Redline ain't cheap and I don't think diffs are that picky.

I don't mean to thread jack, but you seem to be pretty knowledgeable about gear oil, and I have a question. Is the 75w-90 GL-5 non-limited slip gear oil ok to use for both the diffs (rear with e-locker) and transfer case?
 
You can use fluid either with or without LSD additive, it won't matter but most synthetics have it included in the fluid as part of their additive package. I used some Lubro Moly 75w90 GL5 synthetic gear oil in the front, rear, and transfer case, all is well 3 months and about 5k miles later. It's actually a bit pricey but it's excellent stuff and I had several bottles laying around since I use it in all my Mercedes diffs. IIRC Lubro Moly has no additive for LSD in it, but since we don't have a factory LSD we don't need it, with or without the e-locker (I have it).
 
I don't mean to thread jack, but you seem to be pretty knowledgeable about gear oil, and I have a question. Is the 75w-90 GL-5 non-limited slip gear oil ok to use for both the diffs (rear with e-locker) and transfer case?

Absolutely. Lots of people do.
 

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