Doing fluid changes on my 98 4x4 manual transmission Tacoma. What brands do I use?

I heard that the transmission has brass in it and certain gear oils could mess it up? 180k miles and I don't think it was ever changed, along with the differentials and transfer case.

Can I just use Supertech for the diffs and transfer case? Thank you.

 

Only use an oil that is GL-4 rated for transmission, not GL-5 as it will mess up the brass.

 

yes supertech 75w90 full synthetic will work in them at a great price youll probably need replacement gaskets for the diffs(use one time only crushable washers)at the Toyota dealer you can reuse the transfer case washers tho

 

Great. Thanks for the info

 

I use Redline MT-90. Works great as far as I can tell. Had my 5 speed completely rebuilt. Less notchy with the RL. It's GL-4. I also use it my Mazda hatch hence the reason I use it in my Tacoma. Worked well in the commuter so why not the pickup?

 

I ordered that for my transmission. Going to Supertech all the other things though.

 

x2. I use Redline MT90 as well and the first time I used it my trans shifted noticeably smoother.

 

I could only find Supertech 80w90 gear oil. Are my front/rear/tcase going to blow up?

 

no, but the 75w90 is a better full syn, if you go to walmart.com you can open an online account where they can deliver the 75w90 to your store without shipping fees and you just pick it up when it arrives at your walmart store

 

I may end up doing this. I live in Florida so the bottom number shouldn't be an issue, unless the polar magnetosphere begins to shift of course.

 

Supertech Synthetic is GL4/5 and will be fine. I have changed my diff/tcase/tranny fluid many times and never replaced the metal crush washer. No leaks.

I also noticed a great improvement in shifting when swapping out the old Valvoline dino with new Supertech Synthetic. I originally thought "golly gee, this synthetic oil is nifty!", then quickly realized that ANY *FRESH* oil will make shifting better, especially when changing out 50k mile oil. I don't believe in the MT90 especially not for the price. 190k on my truck, no issues running cheap shit. I went a little thicker in the rear though, 80w-90 with a smidge of 85w-140. Only because of the larger tires and I wheel it.

 

ive used the walmart online to buy stuff that my store didn't have and picked when it arrived or picked up at another store that has it

 

$29 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 and 80w-90 are the same oil. Any gear oil that still carries the 75w-90 label is new old stock. The SAE revised their ratings a few years back. Just a FYI.

I'm not sure what ST goes for these days but I've had good luck with Valvoline & Mobil 1 over the years.

 

I guess I'll keep the 80w-90 then. I paid ~$14 for the gallon

 

Op I would get all new washers anyway for transfer case (fill/drain), diffs(fill/drain), transmission, and oil pan.

It’s only a few bucks and you have good peace of mind that they won’t leak.

 

OP save your money and don't buy the transfer case gaskets/washers they are reusable type you will only need to replace the crushable type gaskets/washers you'll need 3, Toyota part #

$15 12157-10010 Toyota Oil Drain Plug Crushable Steel Gaskets Set of 10 OEM 12157-10010

12157-10010 crush washers all the rest are reusable and will not cause any leakages.

 

Lol

 

which ones are those? I've never replaced any of these washers. Never been an issue. Hell, you can reuse crush washers multiple times anyways, in my experience at least.

 

I had a hard time finding a 24mm socket so I got a 15/16 instead.

 

supposedly the crush washers are one and done after you torque them to spec, because reusing them MAY lead to leakage or even stripping the plug since they are designed to seal at the prescribed torque.