Redline MT-90 synthetic gear oil
Redline MT-90 synthetic gear oil
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Description
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).
Instructions
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What does it fit?
Emissions
Emissions do not apply.
Warranty
none
SKU
I used MT-90 as recommended by FM on my ND1 that was bought used with 46k miles. Since there was no record of a transmission oil change, I replaced it for peace of mind. It behaves exactly like FM described, which is slightly more effort when cold and slightly lighter when warmed. Good stuff!
I was previously using Redline MTL and it was definitely not the right choice for my ND2. Even new, the gearbox felt a bit more crunchy. After 1 track day it degraded significantly and felt even worse. FM is right for using MT90. It's a little coarse before warming up, once it does the gearbox is incredibly smooth. Even on track and after the gearbox feels excellent.
Replaced factory fill at 10k miles. Shifting is noticeably smoother - highly recommended! I did need a little more than 2 quarts.
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.
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.