Real world. Mpg

[Sparkysikes]

I want to LS Swap my c3500 crew cab dually. Either 5.3 or 6.0 (LQ4)

Has anyone done this and how is their freeway mpg. Not theoretical. Also what freeway gears you have

Currently my 6.5td gets around 12 mpg empty or loaded. Best highway MPG ever was 15.7

 

[stutaeng]

I've got a 00 K3500 CCLB SRW 5.7/4.10s, but I don't drive it enough to want me to check MPG information.

I DD a 06 Suburban 2500 LQ4/4.10 2wd and that one says like 12.something on the cluster when I bought it, and hasn't changed. City vs highway doesn't seem to make a difference. Not a direct comparison, but you get an idea. In my opinion, MPG is more related to how heavy the vehicle is, than power... on a naturally aspirated engine of course. I think these heavy trucks don't do better than 11-13 MPG.

I'd say the 6.0 is going to be a better option for you. Look into the GMT800 3500 2wd DRW with the 6.0 engine for MPG. I think the empty weights of those and your truck will be similar for an apples to apples comparison.

 

[smokymtn65]

6.5 Burb 15.6 ave best 18
6.2 k-10 18 ave best 21
7.4l no idea yet
2010 we measure in gallons per mile LOL
07 15.5 hwy 12.5 round town never been right after delete & tune

 

[L31MaxExpress]

I want to LS Swap my c3500 crew cab dually. Either 5.3 or 6.0 (LQ4)

Has anyone done this and how is their freeway mpg. Not theoretical. Also what freeway gears you have

Currently my 6.5td gets around 12 mpg empty or loaded. Best highway MPG ever was 15.7

You will probably lose 40% MPG with a 6.0L gas compared to the 6.5. 8.1 will get the same mileage as a 6.0L in that heavy pig.

5.3 is a dog in a light truck. I never had a problem leaving 99% of them light to light and beyond in my 5.7L powered Express van.

 

[Sparkysikes]

At that point I'd leave my 6.5 as she pulls like a ***** ape.

 

[TheAutumnWind]

Apples to oranges but its a big heavy suv with a similar engine.. I have an lq9 in an 05 escalade esv platinum. DIC always says around 12 mpg avg with a lot of city miles.

I can get it to say 17 to 18 mpg on highway only.

You should definitely do the 6.0 instead of the 5.3l imho