02/26/2026
So a question we get fairly often is related to transmission service, "when should it be done?" So it depends on how you use it.
The pics you see are of my personal truck, 2022 GMC 2500 6.6l gas with 6L90 six speed automatic. This truck had 17,000mi on it when I got it, now the odometer reads 31,000mi.
Do I tow with it, yes. Often? Maybe I would average twice a month. Would that constitute serve duty service schedule by GM standards. Their definition is "frequent" towing. Doesn't seem like it to me.
All that to say, a transmission service is not on the normal service schedule for this truck, not in 120,000mi. In my opinion we see too many 8 and 10speed transmissions that have 60,000+ miles that have never been touched, and now have shifting issues. When we check fluid condition it more black then the red it should be.
Some issues can be resolved with a service, some it is too far gone. As you know nothing is cheap anymore, especially not 8 and 10 speed transmissions.
We recommend every 30,000mi, in most cases. And for those that plow snow also, don't forget those transfer cases.
Have questions how to best maintain your vehicle for longevity, give us a call. It is still less expensive to maintain than repair/replace vehicles and their major components, in my opinion.
If you made it to the bottom of this post, thanks for listening. I am getting off my soap box now.😏
