I have started looking at new trucks. Don't seem they offer what I thought I wanted. I wanted the iron block 5.3 with 3.73 gears like my 2005.
Seems if you get a 4WD, you get the aluminum block. If 5.3 they have fuel management which shuts it down to 4cyl. I think you can get 3.73 but no one has them. They have 3.42 for the lowest gearing. Maybe with the 6sp auto this isn't an issue.
Questions. Is there any problem with the fuel management system?
What kind of mileage is anyone getting from the 6.2 on the highway. The 6.2 with 3.73 should be a powerhouse.
Thanks
I'm not sure if it is the same. but I drive a 09 Avalanche - which is the same set up as you described.
Because of the new 6 speed automatic transmission, the deepest gears you can get is only the 3:42 ratio.
Again, I am not for sure - but I believe that the block is cast iron, only the heads are aluminum.
Anywho - the all aluminum block - which is the same one that is in my Pontiac Grand Prix GXP = is a very good piece - even better then the cast iron block that was in my 02
Absolutely no problems and the Pontiac was a 303 HP option in 2005 in the Pontiac.
The only problem I have with the 5.3 is the fly by wire, where you do not have a cable that physically connects the gas pedal to the throttle. There is a slight lag between the time you press the accelerator and the time it actually reacts to the input and tells the engine to go.
The 8 cylinder runs when you are going up hill or on the flat and level - while you demand it to accelerate.
The 4 cylinder kicks in when you are going down hill and when you take your foot off the accelerator.
Unless you press the button on the vehicle information center - you would never know which mode it is running in.
It also calculates gas mileage in real time.
I'm getting about 16 MPG around town and about 17 - 18 on a trip with no load.
Add a 7,000 racecar trailer and the gas mileage immediately goes down to about 4 MPG. You have to use the tow / haul mode and it keeps the transmission in a lower gear, longer - which makes the truck get crappy mileage.
No problems with the fuel management system, but you will loose approximately 25% of your fuel mileage when you use E-85 fuel.
This is with 20 inch wheels and fully loaded.
The four wheel drive has worked well, except I don't like having to shut off the traction control to go four wheeling.
No truck should have traction control!
Ground clearance really stinks.
I already tore one front spoiler off in 5000 miles.