I have had both and must say I am IN LOVE with my 2015 5.3L CCSB. Great power and driving characteristics plus it will knock down 16-17 city and 22 highway. The AFM really works very well on the DI motors and I have had instances where the truck will be in V4 at 70 mph on a flat highway.

The interior and creature comforts of the 15 outweigh the 13 by a long shot and the truck just flat out rides smoother and is much more quiet.

Cold air, cat-back and tune should put it right in line power wise with the older 6.2L.

- Beau

 

Anyone have an idea of what the 2015 5.3 CC 2wd or 4wd is running in the 1/4?

 

I feel the new 5.3 runs damn near as strong as the older 6.2.

I really like the 5.3 in mine, runs good and gets good MPG also.

Best highway mileage I've gotten over 100m is 23.8 which is pretty good in my eyes for a crew cab 4x4

 

That gas mileage is great!

 

I love my 2014. Gets 22mpg hwy and around 19 city. Ran it last weekend at the track and ran 14.52 @ 95 spinning with just a tune. Can't wait to fill it up with E85 and add some bolt ons.