57904 75W90 GL-5 Synthetic Gear Oil for Hypoid Limited Slip Differentials - 1 Quart

Great lubricant, lasted in the car for several years.

Exellent

great product for a great price.

best oil for my e46 differential. Recommend on many forums.

Great product, delivered on time !

After hearing about it on a MX5 Forum, I tried it and found it an excellent product. Noticeable difference in the Differential Gear.

Mejor aceite para mi diferencial

Red Line Gear Oil consistently delivers superior performance under high-stress operating conditions, making it an optimal choice for both professional and enthusiast-grade mechanical applications. Engineered with advanced synthetic formulations, this product offers exceptional thermal stability, shear resistance, and long-term protection across a wide range of gear systems. In real-world application, the oil has demonstrably improved drivetrain smoothness, reduced operating noise, and contributed to extended service intervals—resulting in reduced downtime and maintenance overhead. Its performance in high-load and high-temperature scenarios reinforces its reputation as a category leader in gear lubrication.

デフ特有のガリガリ音も少なく効きもとてもいい感じです。 夏場やサーキット走行するにはもっと固めのでもいいかもしれませんが街乗りではとても十分です！

If you are aren't familiar with Red Line automotive lubricant products -- be informed that most knowledgeable mechanics consider it to be the best line of petroleum products available. My cars are all currently FWD, but I have a long history of ownership and maintenance on 4-speed manual transmissions and RWD differential units. Presently, I use this gear oil in the differential of my Yamaha shaft drive motorcycle. My recent experience . . . The original Yamaha factory gear oil had been changed to Valvoline Synthetic at a few thousand miles. At about 16,000 miles on the odometer, I had noticed a little bit of audible gear while decreasing speed down to a stop. I figured it was time for a gear oil change and this time installed the Red Line 75W90 Synthetic Gear Oil. The whine immediately disappeared. Would it have disappeared if I had used any other oil? Probably. Or maybe not. Either way, I really like knowing I have the best lubricant available in the gear unit. I'll should also mention. This stuff is super slick, and claims to reduce heat dramatically and increase efficiency (gas mileage) a few percent (we'll see). It's so slick that the manufacturer suggests that for limited slip applications, a limited-slip additive is probably not needed to eliminate chatter (I recall in years installing a rebuilt Chrysler 8 3/4 posi unit and had to do exactly that -- put in an additive to prevent chatter -- so Redline is claiming I possibly wouldn't have had to do that using their lube -- an interesting claim). UPDATE: After putting about 6,00 miles on this Redline in the differential (motorcycle), I've "touch-tested" regularly, and can report with confidence that this stuff absolutely reduces operating temps. A lot. Even after extended high speed/summer temperature use, the differential temp never got much past "warm to the touch". With the original Yamaha gear oil, it got HOT. This is great stuff.

Excellent customer service, perfect product