I accidentally put this into my manual tranny intending to put MT-90. Is it worthwhile to make the correction? Thanks for any input.

 

What year is your truck? Some of the newer vehicles call for ATF in the manual tranny. Not sure if Toyotas do or not.

Rob

 

my truck is a '00 4runner.

 

This is what Red Line says about their 75W90 NS Gear Oil:

"This GL-5-type gear oil doesn't contain the friction modifiers for limited-slip hypoid differentials. This makes the transmission synchronizers come to equal speeds more quickly, allowing faster shifting and much easier low-temperature shifting. Can also be used in racing limited-slip differentials where weak spring design causes too much wheel spin."

This what Red Line says about their MT-90 Gear Oil:

"Popular in Nissan, Toyota and Mazda manual transmissions and transaxles as well as other selected applications, this is a 75W90 GL-4 Gear Oil that’s slightly heavier than MTL. Provides excellent protection of gears and synchronizers and its balanced slipperiness provides a perfect coefficient of friction, allowing easier shifting."

To sum it up: If the synchronizers in your tranny are sensitive to GL-5, use GL-4. You'll need to check if the synchros in your truck are indeed sensitive to GL-5.

HTH

 

call the dealer

 

You might want to change it (assume you have a manual trans):

"You want to avoid running a GL5 oil in the transmission. The EP additives in a GL5 oil can attack the brass synchro rings on transmissions not rated for GL5 oil (the Toyota transmissions are rated GL4/GL5) and they can make the oil too slippery for proper synchro operation (shifting will feel sluggish - and this does apply to Toyota transmissions)."

from:
http://www.4crawler.com/4x4/index.sh...ntheticGearOil
Also see a thread call "gear oils"

 

Nah, just run it until you want to change the gear oil again. 75w90NS is fine for manual transmissions, especially modern ones like your '00

Next time run MT90 or MTL depending on your climate.