Transmission kick down

[Walkercraig01]

I drive about 29 miles to work everyday one way. Yesterday was the first day i have drove the yukon to work there are some minor hills on the way and my motor is very quick to kick down to yet the power.. I'm wondering if adding a tune or performance parts would prevent the chances of kicking down. I also have a 2003 aviator and it doesn't kick down on the minor hills. When I get some time I'm gonna check the plugs and wires and see how they are. But as beautiful as it runs I think it just got a fresh tune up. Thanks

 

[Deephaven]

What year? If it is the 6 speed you can change almost anything you want on the transmisssion

 

[Walkercraig01]

2004 slt. It drives great and believe all maintain is up to date

 

[Mr. 960]

my 06 ECSB sierra with a 5.3 would climb 6-7 % grades at 75 MPH in over drive and the cruise control on. had a tune and it drives much better, but now it will kick down to 3rd in the same hills. Guess it's all in the tuning.

 

[Walkercraig01]

I'm just looking for better mpg. I get 19.5 on the way home from work according to torque and like 16 according to the vehicle