Redline 75-90 NS: Good tranny lube!

[4wdchico]

I recently put Redline 75-90 NS in the tranny of my '85 SR5. Wow, what a difference, much better shifting, both hot and cold. I thought it shifted pretty good before. I changed the trans fluid 2x with conventional gear oil earlier last year, then went with Sta-Lube Syn-Go 75-90 full synthetic with a moly additive. I put about 6k miles on that filling, mostly on my trip to Colorado.

I went back to Redline because I had such great luck with shifting performance in the t-50 transmissions of the three ae86 GTS's that I had at one point. I ran Redline MT-90 fluid in those trannys. But MT-90 is only GL4 rated and the front diff hypoid ring and pinion set in the t4wd requires a GL5 or above rated gear oil. So I ordered up some 75-90 NS Redline from my local NAPA store. The NS designation means no limited slip additives. Regular Redline gear oils can not be used in our trannys because they have a friction modifier intended for use in limited slip units in them that will stop syncros from working. I have seen it happen, not pretty.

So, now I have an even better shifting trans that is filled with a premium synthetic that is rated at GL6, a very heavy duty extreme pressure standard. I plan on changing it every 10k miles.

[Petros]

Good to know, how much did the lube cost?

[4wdchico]

The Redline NS cost $11.49/qt.

[ccmt]

Can this be used in the rear diff as well?

[The Professor]

I found recently that Red Line has our car listed on its website with various fluid recommendations. I was unsure about their suggestions and messaged them:

Make: Toyota
Model: Tercel 4WD
Year: 1987
Engine Type: 1.5L Gasoline
Differential Size/Type: hypoid open-diff
Transmission Type: hypoid transaxle (like subaru)

Issues: Hello, I was hoping your oil selector would have my vehicle, but it did not. I have a 1987 Toyota Tercel 4WD manual transmission. The factory gear oil weight is 75w140 (maybe 70w? But for sure 140 on the high end). It technically has a transaxle, so the front differential/gears/RWD transfer gears all share the same oil bath, much like a Subaru transmission. These transmissions are obsolete and rebuild parts are no longer available. The gear oil it had when I bought it did not seem terribly old or smelly, and the gears shifted easily with no fuss. I changed the fluid anyway to what was available, 80w90 house brand, and now the transmission is VERY cranky when cold and REALLY doesn’t like 3rd gear anymore (wasn’t a problem until the fluid swap). I have also heard these transmissions have brass parts inside that may require a specific formulation of oil to protect those parts, but I can’t be 100% positive. What oil would you recommend I use to resolve the grinding and cold weather performance? Thanks!~

Recommendations: Looking for a 70/75w140 that is safe for this transaxle. I read your application guide for this vehicle and while it mentioned protection for brass parts, the recommended weight was WAY different that what Toyota spec'd for this transmission. Just want to make sure I'm choosing the best product that will alleviate the grinding that started after I changed out the fluid.



The reply:

Thank you for contacting Red Line Oil, in your Tercel manual transaxle I show a 75W90 or 80W90 GL-4 or GL-5 is called for, the MT-90 would be recommended. If a 75W140 viscosity is called for in the factory owners manual the 75W140NS would be suitable.
If current cold shiftability is stiff and the 3rd gear synchro isn’t working properly it is likely the current fluid is higher viscsoity than ideal as well as being too slippery.
At low temperature the MT-90 is substantially lower viscosity than the 75W140NS or an 80W90.

Regards, Dave
Red Line Oil

[dlb]

i don't think i've ever seen 75w140 gear oil mentioned for t4s. where did you read that, prof?

[irowiki]

From the FSM:

gear lube.PNG

[SynthDesign]

I've personally had horrible luck running redline in our 4WD trans'. I was actually too sticky so to speak. I had frothing from the vent breather and issues getting in and out of 4WD. Going back to 75w90 blended synthetic Mobil solved it in 1 fluid change. I use Redline in all my other now Tercel vehicles including my MR2 and Benz.

[larry mcgrath]

Synth, glad to see your still here. Larry

[ccmt]

Synth, is this the stuff you're using: http://www.amazon.com/dp/B000ONZXPK/ref ... B009NGELU2

I'm not getting a great shift from 2nd to 3rd with the Redline so I think I might do a couple 50/50 flushes and then switch to the Mobil.