On orders over $100
100% Money Back on Select Parts
Product images
Product Media
Red Line MT90 Manual Transmission Lubricant 1QT (Part Number: )
Red Line MT90 Manual Transmission Lubricant 1QT (Part Number: )
Red Line MT90 Manual Transmission Lubricant 1QT
Read 3 Reviews | 2 Q&As
Part # 50304

In stock! Ships same day
Universal part

Features & Product Details

Red Line Oil's MTL and MT-90 are designed to provide excellent protection and improved shiftability for manual transmissions and transaxles, having cured the problem of hard shifting in thousands of transmissions with shifting troubles. How? They have the appropriate coefficient of friction for most manual transmission synchronizers (many gear oils, engine oils, and ATFs are too slippery for proper synchro engagement). And, the wide viscosity of MTL and MT-90 allow proper shifting over the entire temperature range which the transmission will experience.

The synthetic base oils used have a very high viscosity index which provides relatively constant viscosity as temperature changes. MTL is a low 70W at very low temperatures and a high 80W, nearly an 85W, at elevated temperatures, providing adequate viscosity to prevent wear and deaden gear noise. MT-90 is a thicker 75W90 version of MTL. The shear stability and oxidation stability of these products are excellent, thus the physical characteristics of Red Line MTL and MT-90 will change little with use.

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.


Brand: Red Line
Class: GL4
Friction Modifier: No
Type: Synthetic
Volume: 1 qt
Color: Yellow
Mfgr. Warranty: No Warranty
Condition: New Product
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.



3 Reviews
4.7 out of 5 Stars
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
Customer Photos and Videos
No user media. You can upload a photo or video of your install by posting a review.
1 of 1 people found the following review helpful
Used this in My Evo X Shifts so much smoother! 6 years ago
5out of 5stars

I did my 60K fluid change on my Evo X GSR and did the Redline Trans Fluid Cocktail. Transmission feels a lot better and shifts very smooth! 2qt of MT90 and 1qt of MTL = Smooth shifting and happy driver :)
Was this review helpful?
Does what it's supposed to do 6 years ago
4out of 5stars

I decided to try out this fluid for a change. It works alright, you really have to get it hot for it to shift smooth. It's winter here now, but I'm sure in the summer when the temps can get a little higher the gears will go in smoother.
Was this review helpful?
Love this stuff 7 years ago
5out of 5stars

I did the recommended 70k transmission fluid change and used the MT90 as the new juice. The Mazda3 transmission is already known to be incredibly smooth but over the last 20k I had noticed it was getting a tad notchy, especially when cold. Immediately after putting this fluid I could feel the difference. Everything is smooth as can be and I could not be happier.
Was this review helpful?


  • Q: Transmission “lubricant”  Aaron Blumenberg12 months ago

    Can I use 4 quarts of this to fill the transmission in my 2004 Subaru STi? It says it’s a lubricant and not an oil, so I’m not sure. If not... recommend trans fluid for an 2004 STi?
  • Q: Transmission tank size  kingofkingz33885473 years ago

    I have a 2013 wrx hatch and I need to drain and fill the transmission. Any recommendations on which is the best and do I need to mix it with gear oil? And how many would I need?
    • 0 of 0 people found the following answer helpful

      A:  WRX transmissions have a capacity of about three and a half quarts. This fluid is not recommended, and we suggest using a 75W90 gear oil for the transmission.

      Zach G. @ RallySport Direct 3 years ago  
      Was this answer helpful?

This Part Fits

Universal Product
This item is non application specific.
Please verify compatibility before purchase. May require some modification for proper installation.