New GM 2500 6.0/6 spd combo

[Z-Michigan]

The 315 HP 5.3L has Active Fuel Management (or similiar), where it runs on 4 cylinders until more power is needed. Is this available with the 6.0L?

As far as I know, AFM is only available on the 5.3L engine in the 1500 series (or smaller GM vehicles). It might be available on the 6.2L used in the Escalade and Yukon Denali, but I'm 99% sure it is not available in the 6.0L used in 2500 and 3500 series trucks.

I have a 5.3L and find the AFM a useful feature. My 2007 Suburban 4x4 gets 16-17mpg in routine driving (except in the recent bitter cold weather) and as high as 20mpg on the freeway in ideal conditions.

 

[RollingsFarms]

As far as I know, AFM is only available on the 5.3L engine in the 1500 series (or smaller GM vehicles). It might be available on the 6.2L used in the Escalade and Yukon Denali, but I'm 99% sure it is not available in the 6.0L used in 2500 and 3500 series trucks.

I have a 5.3L and find the AFM a useful feature. My 2007 Suburban 4x4 gets 16-17mpg in routine driving (except in the recent bitter cold weather) and as high as 20mpg on the freeway in ideal conditions.

from what i've read and been told, the 4.8 is not AFM. the 6.0 in the 1/2 tons(Vortec max)is AFM but not in the HD's. many people were scared of the AFM in the 5.3 and opted for the 4.8 when the 2007's were first released.

 

[asylum575]

Thanks for all the replies. I will more than likely go with the 5.3AFM w/3.73 gears. Seems like it will fit my needs. I like, don't love my current 6.0, but the MPG are the pits. I've seen a bunch of leftover 07 crew cabs with the 4.8 and 3.42 gears. Not a good towing combination. Will try to hunt down a 5.3.
Funny thing, the other day my wife and I were watching the news and they were showing a local auto show. The reporters were drooling over the Maserati's and Porsche type vehicles. I turned to my wife and reluctantly admitted if I had the choice of a vehicle, I would probably go down to the local GMC shop and get a 3500 Dually with a diesel and allison tranny. Then take the money i'd save from buying an expensive sports car and finish restoring my 65 Stang.
OH MY GOD, I've turned into my father.

 

[bigtiller]

I just bought an 07 new body ext. cab 2500 HD,in Dec. with a 373 rear end. From day1 I have gotten 15 mpg, mainly highway. Pulling a 2horse trailer with the trailer tow on I drop to 9.5. This is a fast truck with 360 hp. I run about 70 (give or take). I was told if I had the 410 rear my mpg would be awful. I was a ford guy ( and still like Ford) but the 5.4 is gutless compared to the 6.0. I decided that the duramax was to much and couldnt justify buying it. Later John

I will second TX48. I have a GMC 07 ext. cab 2500HD 4X4 with 373 gears and 6 speed auto. I drove 564 interstate miles on a calm cool day and got 16.6 mpg at about 70 mph empty. Pulling my tandem axle trailer with a 2500 pound load dropped it to 10.

 

[zzvyb6]

I have the 6.0l + 6 speed in my 2008 Yukon XL AWD (=Suburban wheelbase size).

You can yank a trailer pretty quick with this setup. I have the rear camera, too, and that has ended all pain for backing up to hitch up a trailer.

MPG is about the same as my 2007 5l Tahoe with AFM (having 4 cyl mode)

The problem I have is that the truck has so much grunt and the tailpipe sound is such a viagra trip, that its hard to stay out of max throttle at a signal. When using some discipline, I get 17.5 to 18.5 mpg. Same as the Tahoe overall. A bit less when dragstrip action is happening. The Big Dodges and Fords give up at about 2nd gear.

BTW: that's 1800 rpm at 70mph for you geeksters. The rpm reduction gives the big motor an advantage. The sound alone was worth the money... Even the dogs know when I'm sneakin' up the driveway at midnight....

 

[asylum575]

Wow, 16-17MPG with the 6.0/ 6 spd. That's pretty good. I know what you mean about the grunt. My 6.0/4spd is just begging for me to punch it. Really takes off. As for sound, I had a 2003 Z71 Silverado with the 4.8. I threw a flowmaster and dualled the pipes. Finished it off with some Chevy bowtie chrome tips. Man, loved that sound. My wife hated the rumble in the morning as I went off to work. Been tempted to do the exhaust on the 6.0. Purely for fuel economy purposes, wink, wink. Maybe the 2500 series and the 6.0/6spd setup won't be too bad. Just seems to be alot of 2007 leftovers out there and few 5.3s out there. I'd be very happy with 16-18MPG compared to the 10-11MPG of the current setup.

 

[Diamondpilot]

If you like your current truck keep it. I see this mistake made all the time. Guys trading to get better millage. Lets say your current truck gets 12mpg and the new one gets 16 mpg. The 12mpg truck cost $0.19 per mile to drive and the 16mpg truck cost $0.25 per mile with gas costing $3.00 per gallon. Lets say you lose $5,000.00 on your truck. It will take you 83,333 miles to break even. If you lose $10,000.00 it will take you 166,666 miles to break even. You will end up with 1 more year of payments if you do the same loan terms, higher insurance on the new truck, ect. At the end of the day you gain nothing, you lose.

A guy I work with has a 2003 GMC that he claims 18mpg. He just bought a used 2004 VW Beetle to save money on gas. I brought to his attention he spent 12k on the car, plates, insurance, maintenance. I bet he will need 300,000 miles to come close to breaking even.

Chris

 

[asylum575]

Good point Diamond pilot,
Fuel economy isn't the only reason I'm looking for a new truck.
1- Is the fuel economy
2- 2006 GM vehicles have 3/36 warranty new have 5/100 on powertrain
3- Current truck is 2WD, would prefer 4WD
4- I've convinced the misses it's good move

 

[Diamondpilot]

If you have the misses convinced that is all that matters.

Chris

 

[Builder]

Thanks for all the replies. I will more than likely go with the 5.3AFM w/3.73 gears. Seems like it will fit my needs. I like, don't love my current 6.0, but the MPG are the pits. I've seen a bunch of leftover 07 crew cabs with the 4.8 and 3.42 gears. Not a good towing combination. Will try to hunt down a 5.3.
Funny thing, the other day my wife and I were watching the news and they were showing a local auto show. The reporters were drooling over the Maserati's and Porsche type vehicles. I turned to my wife and reluctantly admitted if I had the choice of a vehicle, I would probably go down to the local GMC shop and get a 3500 Dually with a diesel and allison tranny. Then take the money i'd save from buying an expensive sports car and finish restoring my 65 Stang.
OH MY GOD, I've turned into my father.

Naaahhh, that's normal.

I don't want some upitty richy-rich guy's sports car, either. I'd rather buy something that is a thrill to drive, makes me some money, tows my junk around, goes great in snow, etc..