I have a 2023 Corvette HTC, Stingray that was purchased on June 6th, 2023. I have 6000 miles on it, and coming up to my 3yr trans oil flush interval based on the letter that GM sent out. I am not at the 7500 mile mark, and will most likely take me another 2-3 months to hit that mileage mark. My question is will I void my warranty if I hold off on changing the trans fluid until I hit the 7500 mile mark and do both oil and filter at the same time? My dealer is telling me that I need to do both now, and then the filter again at 7500 miles, which is NOT what the GM letter is saying, so just looking to confirm what will void the warranty and what won't. I can't imagine another 2 months on the trans fluid will make a difference, but I want to make sure I don't void the warranty.

 

Welcome to the forums. That's a good question. According to GM the fluid should be changed at 7500 miles plus or minus 500 miles, and it's not beneficial to replace the oil and filter before that mileage. 7000 to 8000k miles is the service window. The warranty is another good question for GM. There is an extension added in 2024 and later but I'm sure how that effects 2023s.

 

Welcome to the forum. First, GM has removed the flush requirement since if you drive a couple of miles or more to get the service done, the fluid is basically flushed
through the filter during that time. The transmission fluid has a 3-year life span and should be changed at or before that point in time. I just had mine changed recently at the 3-year point with only 5,000 miles and may have to do it again at 7,500 miles but I'm not sure but will check at that point in time because it seems like they keep moving the goal post on this requirement. I am not sure how critical the 3-year mark is but I advise checking one of the containers of fluid to make sure it has 3 years left on it.