6L90 Pan Drop Question

[UltimateToolReviews]

Hi Everyone, I am planning on doing the pan drop fluid+filter change on my 22 2500 and there is very little on Youtube/elsewhere on info about it. I've done this before on other trucks, but I always like to be 100% on transmissions as they can be fussy. Explain to me like I am 5 as I am basically trying to find the easiest way to do this without a lift.

 

1. I see you can add fluid on the drivers side fill port, any reason I can't just add the 6 quarts back into the clean pan and bolt it back up? Yeah it's harder, but far easier to measure and it will be exactly as it was before.

2. Best place to get the filter and gasket? (I know Amazon and rock auto are good options)

3. Do I need to have the truck running and the transmission at operating temp for the pan drop change? See question 1.

 

Thanks for your help!

[CamGTP]

No way I'd fill the pan with fluid and try to bolt it up, you're going to make a mess doing that. Just fill the transmission through the dipstick tube. Measure what you take out and dump the same amount back in, check the level and add as needed.

 

The GM Dealer or any auto parts store to be honest, the filters are pretty generic and a good filter is going to do the job. The pan gasket should be a rubber coated metal gasket. I always clean them and reuse them because that is how they are designed. Or get a new rubber coated metal gasket. Napa usually sells a kit with a new gasket that is that style.

 

Change the transmission with it cold, unless you want to take a hot transmission shower if you aren't careful. Bolt everything back up and fill it will fluid, then let it run for a while to build heat. Check your level and go for a drive, get the transmission nice and hot with some more aggressive driving, then recheck the fluid level.

[UltimateToolReviews]

Thanks for the help, I wish these trucks had a transmission dipstick, probably will be a mod for the future.

[CamGTP]

Oh yeah that's right, GM removed the dipstick on the new body style trucks.

[Pryme]

5 hours ago, UltimateToolReviews said:

Thanks for the help, I wish these trucks had a transmission dipstick, probably will be a mod for the future.

It’s a very easy mod. I did it in about 30min. There is a sticky with part numbers. 

[UltimateToolReviews]

Sweet, I will install that first. Dip stick is always an easy way to add fluid. 

 

Edit - Dang, I can't find the dipstick parts in stock anywhere for a resonable price, everyone wants more for shipping than the part is worth. Waiting for rock auto to get it back in stock.

Edited April 28, 2025 by UltimateToolReviews