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Redline MTL synthetic gear oil

Redline MTL synthetic gear oil

Regular price $22.99 USD
Regular price Sale price $22.99 USD
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Redline MTL is a 75w80 synthetic has been the go-to fluid for Miata owners since the beginning. Smooth, accurate shifting due to the special additives for the synchros. It's what we use in most of our own cars.

Pure track cars should use MT-90 - it's not as happy when it's cold, but it will deal better with the high temperatures of the track. We also recommend the MT-90 for ND Miatas, as it is very close to the stock formulation.

For maximum gearbox protection on hard-driven track cars, mix in a quart of Shockproof gear oil.

NB 6-speeds require two quarts, all other Miata transmissions require three quarts (the third quart is used in the shift turret).


Instructions are not currently available.


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Customer Reviews

Based on 5 reviews
I prefer MT-90 for my MSM 6 speed.

Perhaps it's unfair to give a poor rating to a product that's not even recommended by either manufacturer.
Both Mazda & Red Line recommend 75W90 GL-4 for the Mazdaspeed MX-5, and I'll be staying with MT-90.
My gearbox is much happier now that I've replaced the 'old' MTL with 'fresh' MT-90.
My experience is the opposite to that of Flyin' Miata.

Not bad

I used this on my NB1 6-speed transmission for the past two years. My shifts felt ever-so-slightly better than whatever came out of the transmission, but nothing to write home about. This fluid will get the job done satisfactorily. I would trust this over whatever you can find in an auto parts store.

Robert i.L.
Works fine, but Red Line recommends, on their website, is MT-90 75W90 GL-4 gear oil.

Miata gear boxes were designed before synthetics were commonly used in gear boxes. Our boxes have large clearances, and Red Line currently recommends a heavier oil than this for our boxes. The oil that Red Line recommends, on their website, is MT-90 75W90 GL-4 gear oil. This said, many of us have used MTL for years, and have been fine with it.

Wouldn’t recommend it

The combination of this and the shockproof only lasted me 5 months. Now I gotta change the fluid because getting into gears is a little rough


Tried this alone and in combination with Redline's Shockproof Gear Oil, and both resulted in better gearbox action than stock fluid (only slightly) but neither compare to Motorcraft Manual transmission fluid. Talking to other Miata owners and searching the forums, you'll find the Motorcraft fluid is actually the favorite of Miata owners and for good reason! It noticeably improved the shifting action of my 200,000+ mile transmission.