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Redline MT-90 synthetic gear oil

Redline MT-90 synthetic gear oil

Regular price $22.99 USD
Regular price Sale price $22.99 USD
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More expected on Mar 2, 2024.




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Emissions: Emissions do not apply.

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Redline MT-90 is a great gearbox lubricant for 'boxes that have to work hard. It's not the best choice for street cars because it needs to be up to full temperature to work properly, but if you're doing a lot of track work or need a little more protection for your gearbox it's the one to choose.

Recommended for street and track driven NDs. For street NA/NB/NC cars we recommend MTL.

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

Customer Reviews

Based on 4 reviews
Jonathan M.
Smoothed out my ND

Replaced factory fill at 10k miles. Shifting is noticeably smoother - highly recommended! I did need a little more than 2 quarts.

Gabe P.
Not suggested for the ND

I used this per FMs recommendation on my ND. Transmission was brand new, literally directly from the Mazda dealer. I installed it in my ND and I’m sad to say that my transmission is already going out. I do drive it harder than average and get it hot, which is why I opted for this fluid, however, I do not believe this fluid was the correct choice and I’m very disappointed in the product, at least in terms of the ND.

Per customer, via Ethan, don't publish. Unlikely to change, leaving here just in case.

MT-90 is much better than MTL for my MSM 6 speed.

MT-90 is the Mazda (and Red Line) recommended viscosity, and I agree.
The previous owner went with MTL (28000 miles) in the gearbox and I've always found 1st to 2nd notchy until the car was up to temperature.
I just installed MT-90 (61000 miles) and all is well.

Robert i.L.
This is the oil that Red Line recommends for a Miata 5 speed box.

The oil that Red Line recommends, on their website, for our gear boxes is MT-90 75W90 GL-4 gear oil. Our gear boxes were designed for convention (non-synthetic oils) and the clearances are relatively large, larger than for a modern box. A correspondingly heavier oil works well in our boxes, especially for severe applications and boosted cars.