Hello, i currently have a 2005 6.0 awd escalade that has way more motor than what i need for hauling my family around, and the motor has 225k on it so in the future im looking to swap in a 4.8 from the same year. I realize that the computer will need tuned due to the difference in stroke and displacement probably impacting injector pulse widths (not sure), thankfully in ohio we have place that can do such a tune. Are there any known complications thatll arrise? Keep in mind this is for less power and more mpg, im used to 1.5l-1.6l compact cars and have driven a fully loaded 4.8 box truck as well as a couple passenger trucks with them, so im not concerned about it having too little power to get the job done. I do not intend to race or tow with it. Thanks for any help!

 

You can get a mpg friendly tune, or smaller wheels and tires. If that's all you want, then sell the escalade since it's also the heaviest of the bunch and get a tahoe with the 4.8L. I'm sure if you ask around on the right board, or locally, you can trade and have them put cash on top.

 

I already have the escalade, i dont have $8000-$10000 to buy such a tahoe as in ohio they are either rusted to death or plenty expensive. My question was is there anything im not accounting for in regards to the swap, not "what different suvs would get better gas mileage", so the comment to just buy a different vehicle isnt really helpful.

 

4.8 you’ll end up with worse mileage. Will require higher rev to do push a heavy *** truck

 

Ive driven several 4.8 vehicles with more load than i will ever put on it hauling my children around and they got much better mileage and didnt struggle a bit.

 

So you think a tahoe is $8-$10K, and the escalade wouldn't be worth as much? Good NBS tahoes are 5K in the southern states, and good NNBS tahoes are 7K. It's less than $1k to ship em anywhere in the country.

Well not sure what load you're referring to, but an escalade, is 10%-15%, OR 500 to almost 1K lbs heavier than an equal Tahoe or Yukon that would have come with a 4.8L. If that was a pickup, they are even lighter. Unless you put a thousand pounds in the bed, or filled all of those seats with kids, you didn't equally compare a 4.8L equipped vehicle to the weight of yours sitting there empty.
The 4.8L stock, just has a terrible torque curve. It does half it's power below 4K rpm. I'll go ahead and let you have fun with your thread after this, I would bet anything you will not only get worse mileage after you do this, but you can easily improve your mpg to as good or better than a stock tahoe with just a tune designed for it.

 

What is your current mileage? I’d be EXTREMELY surprised if you get better mileage out of it.

I suggest a Rav4 or a highlander lol


Anyway your question was about complications. No, just need a tune and it will be good.

 

OP, you may not see it, but it just isn't about the engine. People swap 4.8Ls out and put in 6.0 and get right about the same mileage, and some even get better when driving without the extra fun. It just isn't the engine that is your MPG problem, it's the weight of the escalade.
The 4.8L is about 1mpg highway and city better than the 5.3 IN A TAHOE
The 5.3L is about 1mpg highway and city better than a 6.0 IN THE SAME ESCALADE
A tahoe/yukon is about 1mpg highway better than an escalade.

The Escalade weighs 10-15% more than a Tahoe. If you have stop lights and stop signs, you will not improve your mpg. You're planning on doing a lot of work to accomplish nothing but give you less power.

 

Yeah, no complications going from a 6.0 to 4.8. Just a tune for what they call "segment swap." Everything is identical on the LS family of engines, be it the 4.8, 5.3 or 6.0.

Isn't the bad MPG related to the AWD? It's a full time AWD, right? You can't turn it off? The owners manual of my suburban says "auto" gets slightly less fuel mileage than "2H" IIRC.

Oddly enough, for several years the 2500 Express Vans/Box vans came with 4.8s and 6.0s (either mated with 4L80e), but no 5.3s. The 5.3s were only on the 1500 vans. Not sure why GM did that.

 

The Denali/Escalades were full time AWD, it's not a selectable transfercase. I don't know that it would actually get better MPG with a 4.8L, it's a heavy rig and demands a certain amount of power to move it efficiently.

You might drop down to a 5.3L, get a custom tune focused on MPG and then make sure all the vitals are in good shape, proper tire air pressure, no dragging brakes, front end parts in good shape so as to not be pulling/dragging, etc.

Any Cadillac is pretty much the exact opposite of conservative, it's all about luxury and style, which usually means weight in a vehicle and MPG is totally an afterthought.