Owners manual, hah I wish. Im looking into getting one. Ill just use the info from your site. Thanks again

by the way 4crawler awsome site!

Since the redline stuff is cheaper in 1 gal jugs I got 1 of MT-90 and used it in the tranny (W56) and tcase and had some left over. One gallon of 75W90 was enough for both diffs, I got a couple quarts extra just so I would have enough but it wasn't needed. I would recommend that you get a little extra, don't want to come up short! The MT-90 is awesome in the tranny btw, shifts like buttah, even in the lovely Icelandic weather. The numbers that the manual states for quantities are based on bone dry diffs/tranny/tcase so you will use less, sometimes much less. I know the stuff is pricey but how often do you change it? Redline rocks!

I just bought the truck so this will be the first change. But in all my past trucks I change it about every 6 mounths. probaly to often. But im anal <img src="/forums/images/graemlins/butwiggle.gif" alt="" /> about the fluids.

Sorry, that question was supposed to be rhetorical <img src="/forums/images/graemlins/wink.gif" alt="" /> What I was gettting at was if you are going to drop $100 on fluids for one change are you gonna leave it in a while. I won't change mine until I see evidence of water in it from water crossings. I don't think it will ever break down enough to warrant changing it.

I have redline MT90 GL4 in my trany/tcase. When the guy rebuilt my tranny he told me, "GL5 is what Toyota recomends" When I tried to leave in the morning and it was about 20deg, reverse didn't work... Neither did 1st or 2nd. I had to cram it into 3rd and try to move that way. Arg... Once the tranny warmed up it all worked but I still didn't like it. Expecially since I dropped a mint to rebuild the tranny right.. (Toyota synchs, bearings, seals, couple sleaves and gears... All Toyota...)

Found out he put Shell 85-90 GL5 in it... I was pissed... I used Valvoline Druablend GL4 in it and I told him thats what I wanted. He said he'd pull it apart and change those gears out, only payin for the gears but I knew it was the fluid.

I ordered the Redline MT90 and had him put it in. He bauked at me and told me it wasn't going to work and sure enough... It did.

Lesson learned. Do not use GL5 high weight oil. It doesn't work in the cold. Redline has worked flawlessly for me. And as an added bonus, it doesn't smell and washes right out of clothes. I can't think of anything more repulsive than used gear oil. I'd pay the extra money just for that! <img src="/forums/images/graemlins/cheers.gif" alt="" />

Josh

Two issues at work there, Toyota lists either GL4 or GL5 oil in the tranny. Most likely that means that the tranny internals won't be damaged by the EP additives in GL5 oil, which can attack certain alloys of "yellow metal" parts like synchros. But that said, GL5 oil is too slippery due to those same additives and that makes the synchros slip instead of grip, so shifting is slower.

- GL5 oil is designed for use in applications where gear teeth slide past each other, such as in helical cut gears like a ring and pinion. The EP additives keep the oil molecules from shearing apart as the gear teeth slide past each other.

- GL4 oil is made for applications where gear teeth don't slide by each other, like the straight and bevel cut gears in a transmission and transfer case. The GL4 oil is better at cushioning the straight on gear teeth contact and since there is much less sliding contact, it can have a higher coeeficient of friction, which helps the synchros grab and spin up faster.

Then, the weight (or vicosity) of the oil can influence shifting. The important spec is the first number, which is the cold weight, or cold viscosicty. A 75Wxx oil is thinner than an 80Wxx or 85Wxx oil when cold. The thinner oil will shift better when cold. The 2nd number is the hot viscosity, so a 75W90 viscocity is the same hot as an 80W90 or 85W90. So for best cold shifting, get a smaller 1st number.

Generally, a synthetic gear oil will have a wider spread between the cold and hot viscosities than a conventional oil, since the synthetic oil molecules are designed to resist thinning at high temperatures without the need for as much viscosity improver as a conventional oil.

With gear oils, at least with GL4 and GL5 ratings, its not that one is better than the other, it all depends on the application. Use a GL4 in the axle and it won't work very well, likewise use a GL5 in a manual tranny and again it won't work very well. Use the correct oil for the application.

Hah, <img src="/forums/images/graemlins/notooth.gif" alt="" /> <img src="/forums/images/graemlins/notooth.gif" alt="" /> duh. I ansewered the post at like 4 in the morning. So so my brain wasnt exactly firing on all the cylinders

I don't know if they mismarked it or looked at a wrong number or if it was legit but my local Carquest dealer had Redlone MT-90 for $6.99/Qt. I didn't want to ask so I just bought and left quickly.