

⚙️ Shift smoother, last longer — the ultimate manual transmission upgrade!
Red Line 50304 MT-90 is a premium 75W-90 GL-4 rated manual transmission and transaxle lubricant designed to protect gears and synchronizers, ensuring longer component life and smoother shifting. Sold in a convenient 12-quart pack, it’s engineered for high performance across diverse driving conditions and is favored by professionals for its reliability and ease of use.













































| ASIN | B005JVFC5S |
| Best Sellers Rank | #2,345 in Automotive ( See Top 100 in Automotive ) #4 in Gear Oils |
| Brand | Red Line |
| Date First Available | February 11, 2015 |
| Global Trade Identification Number | 00083522503242 |
| Is Discontinued By Manufacturer | No |
| Item Form | Oil |
| Item Weight | 25 pounds |
| Item model number | 50324 |
| Liquid Volume | 384 Fluid Ounces |
| Manufacturer | Red Line |
| Material | Oil |
| Number of Items | 12 |
| Package Information | Bottle |
| Product Dimensions | 16.5 x 12.3 x 9.6 inches |
| Recommended Uses For Product | Lube |
| Specific Uses For Product | Lubricating manual transmissions and transaxles, protecting gears and synchronizers, ensuring proper shifting in various vehicles and operating conditions |
| UPC | 083522503242 |
| Unit Count | 384 Fluid Ounces |
| Viscosity | 75W-90 |
M**N
1st gen tacoma gold
2003 Toyota Tacoma 2.7L - 4x4 - 5spd manual Box was well packaged and sealed in a plastic bag (think mine was double layer plastic). By far the best fluid to run in the manual transmission and transfer case. Seriously avoid supertech (walmarts fluid - especially in the differentials). The first time I put this in, I did a flush with walmarts cheap sythentic fluid (75w-90 supertech) for 200miles just to make sure all the metal was out. I would not recommend more than 500 to 2,000 miles on supertech. With supertech synthetic, I accidentally ended up putting 7000 miles on the rear differential which is a higher torque spindle-type differential in most trucks and the temps were incredibly bad. > 180F @ regular 90mph. Really you shouldn't take most spindle type differentials above 75-80mph because of the wear. With amsoil the rear diff dropped down to 120 for the first 15miles and then around 140 at 90mph. - this is with outside temps of 85+. No more steel flaking and rusting. I'd use amsoil in the transfer case and manual transmission but it's not as good as this stuff at the varying temps. + the transmission doesn't get hot like a rear diff with 210,000 miles. And the transfer case barely sees any speed or wear even at the highest mphs. Thank god for brass. Drain bolts are 24mm. I used a tekton 2ft breaker bar and a shallow 24mm socket. Also bought the u-joints for ratchets just in case. Best fluid (lowest temps & smooth) I've found for the differential is amsoil severe gear 75-110 (yes I know the manual calls for 75w-90). Also, 75w-140 has very weird properties. So bigger numbers are not always better. Used valvoline dextron VI for power steering, which is meh after 10k miles. Will change to amsoil. Mobile1 seems best in the engine from a cost and wear perspective. I usually get pennzoil full synthetic because mobile1 is sold out. Pennzoil is nearly as good for the first 3,500 then seems to degrade much faster. Every truck varies. My rear differentials were probably neglected from the previous owner and exceeding the payload rating numerous times or perhaps someone possibly did not try too hard to get the perfect backlash / etc from the factory. These are my recommended milage drain marks: 15,000-25,000 rear diff 30,000+ front diff (will likely look good for you) 25,000 transmission 40,000-60,000 transfer case (unless this takes you years as in acid is more of a factor than viscosity) 30,000 for power steering 7,000 for engine Brake fluid 2 years if you dare :p Save yourself $150-$400, help your car, and buy the good fluid and do the transmission, transfer case, and rear differential yourself. It's easier than an oil change. No filter required. Fill ports offer idiot proof over/under filling assuming you're on level ground. I do it in the walmart parking lot with a 7qt oil container. Some brake cleaner. Scotts shop towels. Gloves (yes plz). Some empty distilled water containers. And a funnel. Might need a partner to hold the empty containers up while you pour the used oil. The front differential requires 10mm and 12mm hex to ratchet attachments and is much more tricky to access. Worth it though. :)
A**.
For manual transmission GL-4
I had trouble finding a GL-4 manual transmission fluid and I think this is a very good product. However I think it's overpriced, but so are most other things in life. This actually smells like transmission fluid and not gear oil. Time will tell how good of a product it is. I want to give 4 stars because I think it's overpriced, but since it's less expensive than Toyota I'll still give it 5 stars
A**M
Miracle Juice!
I put this in a 2002 Chevy Tracker (rebadged Suzuki Vitara) with a 5 speed stick transmission and lever operated transfer case. The factory specification calls for a 75w90 GL4 gear lube in both but a previous owner had put GL5 rear end gear lube in them. GL5 eats at the "yellow metal" brass/bronze used in the gear synchronizers in the transmission and transfer case. As a result of this the transfer case would not shift into low range and the 5 speed stick was very tricky to shift. Hard shifts, having to force it into gear, being stiffer when it was cold, just overall not smooth. I was worried because a friend with a Jeep had a similar occurrence and ended up replacing his whole transmission because it became unshiftable and wouldn't hold gears. Read a review of this Redline and it's specific use for manual transmissions. Figured it couldn't hurt and put it in the transmission and transfer case. IMMEDIATELY it was smoother to shift just sitting in the garage with the engine off. I backed out of the garage and was able to promptly push it into 4lo for the first time since I have owned it. Worked great and I backed right up a small hill without any trouble. Several weeks later it's shifting better and low range is back. I will say the transmission was obviously damaged and the transfer case is still not smooth going into low range but I CAN go into low range now and the transmission is definitely smoother. I can only imagine what this stuff would be like in a transmission in better shape than mine. It's not cheap but considering how hard it is to find GL4 rated 75w90 anymore (I bet your local parts store doesn't have it or has a few quarts at most) I'd highly recommend this Redline product.
M**W
Worth it
Used in my 2002 7.3 with a ZF6. This stuff is awesome transmission is quieter and shifts smooth. Just wish Redline used a bag instead of the hard bottle. It is a real pain to fill the case but worth it.
D**N
Good Stuff
Good stuff!
R**D
FANTASTIC FOR TOYOTA MANUAL
I have a 2015 Scion XB (Toyota) manual transmission and changed it a few weeks ago and used that Ultra 1 GL-4 and my manual transmission started having clunky gear shifts. I just changed it to Red Line MT-90 that's actually recommended by Toyota and what a difference. Immediately felt the shifting smooth as silk. Oh well, live and learn. Buy what's recommended by the mfg because they know what they are talking about. My fault.
M**.
Ottimo prodotto
M**L
Changed out the gl-5 transmission oil that was in my 2006 tacoma to this oil. With the old oil the truck shifted rough and slow, would grind into 3rd gear every shift, felt like a worn synchro. With this new oil the shifts are smooth and it just pops right into the gear. 3rd Gear goes in perfectly 95% of the time, sometimes get some feedback of the synchro when I put it in but its minor compared to before. Would Recommend it for any vehichle especially with brass synchros, but if your owners manual says gl-5 only stick to that. Great oil just pricey might be possible to find it locally for cheaper.
M**S
Viskas gerai.
A**A
Used it in my safari dicor. Awesome performance. but the price is on higher side.
P**K
Ottimo lubrificante, il cambio ora é fluido e non si impunta piu.
Trustpilot
1 week ago
1 month ago