Lucas Oil 10048 Synthetic SAE 75W-90 Gear Oil - 1 Gallon

Excellent gear oil! Provides smooth shifting, reduces noise, and enhances performance in both differentials and manual transmissions. The synthetic formula offers superior thermal stability and wear protection. Works great in extreme temperatures. No leaks or issues after prolonged use. A reliable choice for high-mileage vehicles and heavy-duty applications. Highly recommend!

The shifting is smoother, and I’ve noticed less noise from the differential. It’s easy to use, and I trust the brand for quality.

Great gear oil. Helps prolong the life of your race transmissions & rear ends.

Probably the best gear oil on the market. I have used it for years in Toyota trucks and SUVs. It says it quiets and smooths gears and rattles on the bottle. And it does! Immediate and noticable improvement in 5-speed manual Toyota operations. Also use in rear differential of Tundra, 4Runner, Sienna AWD, and Tacoma. This is the only 75w-90 gear oil I consider or buy.

The manual transmission I pot this in is quieter, and shifts smoother...

quality product ,combined with proper maintence helps me achieve better fuel milage and longer lasting parts.

Great gear oil

That’s what she said…ok, now that that’s out of the way, it’s true that the right lube makes a difference.I had to change the differential cover on my 2024 Silverado 2500HD after hitting a rock while off-roading and peeling the edge of the cover up. It wasn’t catastrophic, but just enough to break the gasket seal and get a slow leak.I ordered a new OEM cover, purchased a gasket from the local Chevy dealer, and decided to try this Lucas Oil 75W90, full synthetic, because that’s what my truck uses and the Lucas was about half the price of the AC Delco lube.It took a couple days for everything to arrive. I noticed the Lucas Oil gallon jug was nicely packaged with no leaks. The labeling read “full synthetic”, with additives to quiet rattles and squeals. So far so good.I pulled my old cover and drained all the old fluid. This is a nearly new 2024 truck with low miles, so the fluid was pretty clean with no metal shavings. Everything looked good. I cleaned the differential out, wiped out as much of the old fluid as possible, and then put it all back together. I added Lucas oil to the right level, checked for leaks, and took a test drive. Everything was great for about the first twenty feet, and then I felt a very distinct and noticeable grinding vibration coming from the rear axle.I drove the truck around the block and knew that the grinding was coming from the differential because it only did it when I was turning.I read a bunch of on line stuff on this subject and decided to leave the fluid in and try cornering a few times to see if the fluid would begin working. After a week it did not.Tonight, I replaced the Lucas oil, which was stillclear and devoid of any metal shavings, with the appropriate AC Delco recommended rear differential lubricant. After everything was installed and filled, I took a test drive. The grinding noise and vibration is gone and the truck is running like it should again.I’m seeing a lot of positive reviews on this site, so I’m guessing this stuff works for some people. It does NOT work for the 2024 Chevy Silverado, though. The oil weights are identical, and both are synthetic. The factory line, though, must have a secret that Lucas does not, because the difference is night and day.