Red Line MT-90 75W90 Gear Oil (1 Quart) - 50304

Recommended for GL-1, GL-3, and GL-4 applications

This 75W90 GL-4 gear oil (similar to 5W40/10W40 engine oil viscosity) is popular in Nissan, Mazda, Mitsubishi, Volkswagen/Audi, Lotus Elise/Exige, and Toyota applications. This fluid offers quicker shifts along witha perfect synchronizer coefficient of friction. It is also safe for brass synchros as it lacks the reactive sulfurs that are found in most GL-5 oils.

This gear oil also offers high performance gear protection and along with longer synchro life. Notchy shifting is eliminated especially in the cold. Satisifies the gear oil viscosity requirements of 75W, 80W and motor oil viscosities of SAE 40, 10W40, and 15W40.

About Red Line gear oil for manual transmissions:

  • Appropriate coefficient of friction for most manual transmission synchronizers (other's synthetic gear oils are often too slippery for proper synchro engagement)
  • Red Line offers lubricants to pinpoint nearly every transmission application
  • MTL, MT-85 & MT-90 are not for use in differentials with hypoid gears
  • Excellent gear and synchro protection, balanced slipperiness for easier shifting in cold climates
  • Excellent for high- and low-mile transmissions
  • Compatible with petroleums and other synthetics
Product match fitment

Red Line MT-90 75W90 Gear Oil (1 Quart) - 50304

Red line logoRed Line
SKU #:
Manual Transmission Gear Oil
OE Numbers:
$17.09 MSRP: $21.99
Careful, this is a universal product. Some parts may require modification depending on application.
Ships within 1 business day
  • Guaranteed to Fit, Guaranteed for Life We guarantee the fit and quality of our parts for life. If it doesn’t meet your expectations send it back for a replacement or refund. Learn more
  • Fitment Verified This product application guide has been tested to ensure it will accurately fit the cars outlined in our fitment guide.
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Customer Reviews

Write a Review Average rating:
5.0 based on 4 review(s)
By: Steve
Tue, Jun 16 at 4:12AM
Great Product Worked Great On Manual Trans Volvo 850

I initially would have sticking shifting when it was cold, but it went away after car warmed up. That all got fixed after drain/fill with new Redline trans fluid, aka gear oil. This Redline worked great and breathed a nice new smoothness back into the shifting. I ordered from FCP based off the reviews for GL4 rated oil and everything around town was GL4-5 combo so I didnt chance it there.

By: Jim
Tue, Nov 4 at 12:34PM

Everywhere I look this oil is highly rated for my transmission. It suffers from "5th gear pop-out" supposedly caused by a design flaw in 1991-1994 Sentras with the FS31R5, 5 speed tranny. I'm too destitute to be able to get it fixed and I don't have the shop space to do it myself (otherwise I would.) But it occurred to me that part of the problem may have to do with having a "quick-change oil" shop top off the tranny with "whatever oil" over the course of two years and a leaking seal that I just ignored. That off-oil may have heightened the problem. Now that I have replaced the seals, this is not to say that just putting the best, correct oil in is going to fix it, but like Bugs Bunny says, "It couldn't hoit!"

By: Dennis76
Wed, Apr 24 at 8:32AM
Great Tranny Fluid!

Changed out oem manual tranny fluid for redline. Totally smooth gear change, especially in the cold start mornings. Will not fade out like oem fluid did with engine mods & hard shifting.

By: Dennis76
Wed, Apr 24 at 8:31AM
Great Tranny Fluid!

Changed out oem manual tranny fluid for redline. Totally smooth gear change, especially in the cold start mornings. Will not fade out like oem fluid did with engine mods & hard shifting.

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