ACDelco GM Original Equipment 10-4034 Dexron LS 75W-90 Gear Oil - 32 oz

I bought this gear oil to replace the differential fluid on my 2018 Camaro SS and so far, so good! I mean it's OEM, so it better work! I had to buy a hand pump to get it flowing, but it was such an easy job, I think anyone can do it. The price seems to have gone up about $10 since I last bought it, but I think it's worth changing out if your car has never had it done before.

Great quality diff fluid to replace on c6 corvette as it did reduce rear axle noise immediately.

The local dealership wanted $40 a quart for this. Um, no. This is why Amazon wins a lot of my business if I can wait for car parts.

You can't go wrong with factory fluids

This is the OE gear oil for the Camaro ZL1. No additive needed.The race prep supplement indicates you should change the rear gear oil at 500 and 1500 miles. When I did this at 500 miles on my 2022 ZL1 there were already a lot of metallic filings on the magnetic drain plug as the gears lapped themselves into a solid fit between mating surfaces. Completely normal. Also, make sure you note the drain and fill holes and ensure you can open the fill hole BEFORE you open the drain hole. Nothing worse than draining your oil and then finding out you can't refill it! These plugs are different than the coolant service ports. Do a little homework and identify them. Mine were on the driver's side for the fill and the bottom for the drain. Very easy process to drain and refill and if the car is level then the 1.2 liter capacity is the same as when it starts to come out the fill hole.

I flushed my diff twice using 6 of these quarts and my rear diff is quiet even in 40 degree temps. I followed the TSB instructions driving in circles etc.

Limited slip additives are already in this oil, so my GM truck's clutch packs for limited slip should be safe. For price & lack of information I deduct one star. Is this product hygroscopic? I have no idea. GM is very ambiguous when it comes to their description of the product. The way GM packages this, I assume products like Redline, or Royal Purple may actually be better. They cost the same or less, and give LS protection. I also only give four stars because this product's price is way up there with racing blends like Royal Purple, Redline, or other high performance racing products. I have no idea what type of synthetic this is. At least Redline tells their customers what they use as a feedstock base for their formulation. Delco, BMW, Volvo, Motorcaft, Mopar, Valvoline all keep it some deep dark secret, so I have no idea what to expect this product to do to certain materials. Just because GM says it is what should be used on GM manual transmissions & rear ends is just not quite good enough. I remember when GM's limited slip was new. My father's 4 speed Positrack dual exhaust 348 6 Pack Offie Impala, went through a clutch pack every 6-8 months.

After changing my gear oil at 5k miles to Mobil 1 gear oil, I started to hear a groan from the rear end while backing up cold and turning. After doing some research, I changed the gear oil to ACDelco Dexron, and my issue was solved.