best diff/tranny/transfer oil

bought the unit with 97 last year now i have 126 and who knows when the last time it was changed...what is the best fluid to use??? i live in vt so it gets pretty cold here but i also put about 20k a year... mostly on the road but we go off road quit a bit also
i did some research and it seems like its between the mobil 1 redline 90w ?
let hear some pro and cons
also sizes of socets and allen wrenches would come in useful

 

You want to know the ins and outs on any oil associated with an automobile, check out the forums at bobistheoilguy.com. I've wasted many hours reading there as I'm fascinated by the testing and data and passion some of those guys have for oil. Prolly similar to my diehard love for Toyota, lol.
That said, I'm partial to Mobil 1 fluids.

 

I run RedLine. 20 yrs

 

Oil threads are full of 100's of opinions, all of which really don't matter. As long as it's gl4/gl5 spec it's good. I used synthetic as it gets very cold here in Nova Scotia, Canada

 

I use Royal Purple, since I get it for a decent price.

 

I use bulk and I'm in a cold part of the world but I'd say any synthetic 75w90 oil is good, there is no difference, the only difference people see is in the actual gearbox.

I'm a fan of changing the oil more frequently over buying better oil.

You'll need a 10mm allen key on a socket and a 24mm socket/wrench.

 

Use the proper GL rating & viscosity for the particular component, as Toyota specifies.

For an 'upgrade', use a synthetic and keep the recommended OCI, or use dino and cut the recommended OCI by 1/2 for severe duty use.

Using off the shelf products is fine, there is no significant added value using boutique products.

 

Manual trans? Redline MT90 75w90 is the best from what I've gathered reading a lot on here. I have some ready to get put into mine, should have it done next week.

 

$31 Ford XT-M5-QS Full Synthetic Manual Transmission Fluid - 1 Quart , black

Ford XT-M5-QS

Many of my Solo II running mates find it another level of smooth over the Redline. And we all had GL4 spec'd boxes. And you can get it at a dealer, no mail order required.

It's not cheap, but worthy of consideration. Especially if you have a bit notchy 1-2 or 2-1. Turned it into butta for me. Tried OE, RP, Redline. Ford won.

 

hmm, I do have a really notchy 1-2...I'll try the Redline first since I've already bought it, if it persists I'll give this other stuff a try. thanks!

 

Royal Purple 75w90 in both diffs & transfer case. 100k mile change interval.

 

Just got 12quarts of RP75w-90 from Amazon for $12.00 per bottle. Ready to do my front, rear, and transfer on the Taco and the wifes 4Runner. Anxious to see how it feels. A little worried that I have a rear bearing that is bad but not really sure how to check it.

 

so you guys just use the same stuff for everything? yes manuel tranny

 

My Theory is this, the best gear oil is the most often changed gear oil synthetic or not. I use the conventional Valvoline white bottle 80w90 (Hard time finding 75w90 around here and somebody told me they are basically the same with an adjustment to the ratings) in the diffs and transfer case. I plan on changing it every 30,000 miles. If you dont want to change as often use a Synthetic or something a little but more robust.

My truck is a 5 speed which had some really notchy shifting until I changed the fluid to the Redline MT-90. If you have a 5 speed I highly recommend using this stuff as do many members on the forum. Its not cheap but worth it in shift feel

$24 Red Line 50304 MT-90 75W-90 GL-4 Manual Transmission and Transaxle Lubricant (MTL)- 1 Quart

https://www.amazon.com/gp/product/B000CPCBEQ/ref=as_li_tl?ie=UTF8

 

MT90 all the way for gearbox. Very expensive but worth it. Made my gearbox feel so smooth.

 

I have used Mobil 1 for everything for as long as I can remember in all my cars, including my Toyota.

All top brands are good, but you pay for packaging and advertising with some brands.

 

So I'm going to change my t-case this weekend, can anyone suggest a gear oil? Manual transmission 6 speed. I've heard a lot of people like redline mt90, any suggestions??

 

to my knowledge you cant get Redline in stores, best to buy online. Based on what I've read on here the MT 90 is the best for shift feel

 

I noticed nothing going to MT90, but it could be everything else worn out.