Trans Shift issues 03 Yukon Xl Denali

[TheAutumnWind]

FWIW I have had the transmission flush done with 3 trailblazers and 1 tahoe and 3 suburbans. All with over 150K. If you don't opt for the flush...then just get a pan drop. If you have the deep pan that will replace about 6 or 7 quarts. The end goal is to replace as much fluid as possible. Because fluid level and condition is a main cause of transmission failure.

100% do a couple pan drops

 

[01ssreda4]

You have a 60 NOT an 80 and it sounds like its on the way out (worn clutch packs). I would suggest finding a good builder who is fair on price and plan to have it done. Here's my recent swap.

http://www.tahoeyukonforum.com/threads/yukon-down-awd-delete-headers-converter-etc.81191/

 

[Chizzychase]

If you do have the 60e then it probably is on its way to a rebuild. Torque converter is starting to go more then likely causing it to shift hard and have a hard time shifting under harsh load. Mine did the same thing and one day I nailed it to pass someone on the highway and it started smelling like clutch and now it's making a grinding noise and whines as I accelerate. So it's rebuild time for me.
My advice is do a service to it but DONT flush it drop the pan and drain as much out as you can and fill it back up with new atf and a new filter and baby the crap out of it all the while you're saving for a rebuild because it will need one soon

 

[adventurenali92]

The 2003 Denali XL came with the 4L60E not the 4L80E. I'd say save for a rebuild as well. I tried all the simple steps with fluid and such and replaced the solenoid pack and it did nothing to fix the problem so I ended up having my 20p6 4L65E trans rebuilt anyways. Not cheap but well worth the money I spent on it.