What MPG gain can be expected from a tune?

[CountryBoy19]

I have a completely stock 5.3L Flex-fuel engine in a Yukon XL. 4l60E & 4.10 gears.

Currently getting around 15-16 mpg. We do a lot of travelling, including interstate. It's not unusual for my cruising RPM to be around 2300-2500 depending on how much I'm pushing my speed. I think that's cutting into highway mileage.

I plan to keep the vehicle for years to come and I plan to keep it as stock as possible in regards to cosmetic & performance mods. But I can't help but wonder if a tune will pay for itself with improved fuel-economy. I don't care 1 bit about performance enhancements etc, it's our family car and I want to shave a bit off the fuel budget. IE, we're on-track to put 25,000 miles on it this year. Even 1 mpg improvement yields about 100 gallons of fuel saved in a year; @ $3/gal that's $300. 2+ mpg improvement pays for a tune the first year...

I know the temptation from most is to say "get the tune" because many here like them for added performance. But realistically, my only consideration is financial cost and potential reduced engine longevity (does a tune for economy just lean the engine out at cruising speed?).

 

[Sasquatch]

In all the research i did prior to getting a tune most people stated that they gained 1-2 mpg after their tune.

I switched to 20 inch wheels right before i got my 93 tune from blackbear so i really didn`t see an increase in mileage due to the weight and larger diameter tires but it remained about the same as with the stock 16 inch wheels so i know it did something to help.

 

[adriver]

I won't try to talk to you into a tune, but if you do decide to get one, I would do e-fans too if you don't have them. I'm not sure what year you have, (and am guessing its 05+ on suburbans/XLs that only has the E-fans too). I'm guessing an XL already has the larger 34 inch radiator but if not its about ($40 used,-$80+ new). Then you need the fans from an 05-06 or 07-13 ($40 used-$70+ new), a harness ($20 if you pull, about $120 new), and you need the pin turned on in the ECU. That comes from an aftermarket adjustment usually $100+. Any one of the tuners will include that in the tune. If it helps the mechanical fan clutch is a semi-common problem that you would be getting rid of before you need to replace it.

+ 1 on everything I have come across says a tune is 1-2mpg increase.

You could get better gears is you're doing that much highway, but I'm guessing its not worth it. I would at least learn up on it, changing gears, and e-fans in case something ever does break and NEEDS to be fixed. At that point, it would definitely be worth changing.

 

[cheyenne383]

ROIs with mods are for significant others, not MPGs....

Get the tune, enjoy the better shifting, reduced torque management, and other notable benefits. If you can keep it at 65 or under you'll see better mileage than a tune will ever provide. I've tuned countless GM trucks and SUVs and never regretted it, the driveability is well worth the money and time but the benefits were never efficiency driven.

If you're really only return driven skip it, I doubt you'll see a serious MPG improvement with anything aside from a gear swap. With 4.10 gears speed is your enemy looking for mileage.

 

[jasonc]

I have a completely stock 5.3L Flex-fuel engine in a Yukon XL. 4l60E & 4.10 gears.

Currently getting around 15-16 mpg. We do a lot of travelling, including interstate. It's not unusual for my cruising RPM to be around 2300-2500 depending on how much I'm pushing my speed. I think that's cutting into highway mileage.

I plan to keep the vehicle for years to come and I plan to keep it as stock as possible in regards to cosmetic & performance mods. But I can't help but wonder if a tune will pay for itself with improved fuel-economy. I don't care 1 bit about performance enhancements etc, it's our family car and I want to shave a bit off the fuel budget. IE, we're on-track to put 25,000 miles on it this year. Even 1 mpg improvement yields about 100 gallons of fuel saved in a year; @ $3/gal that's $300. 2+ mpg improvement pays for a tune the first year...

I know the temptation from most is to say "get the tune" because many here like them for added performance. But realistically, my only consideration is financial cost and potential reduced engine longevity (does a tune for economy just lean the engine out at cruising speed?).

Get a flex fuel emulator to start http://www.pointaengineering.com/Fl...for-GM-GMC-Products-CLICK-FOR-INFO-000001.htm unless you plan on running E85. This is suppose to improve MPG's and sometimes a rough or weird iddle

 

[mikeyss]

My old 05 Tahoe has 4.10 gears and black bear tune, anything over 75mph with a 4L60 will eat your gas, no matter what. But with a tune, it won't have to downshift near as much, saving some of your gas mileage.

 

[adventurenali92]

My old 05 Tahoe has 4.10 gears and black bear tune, anything over 75mph with a 4L60 will eat your gas, no matter what. But with a tune, it won't have to downshift near as much, saving some of your gas mileage.

Also as an added benefit to what he stated, the tune optimizes shifting patterns. Shifting less and much more smooth shift points will give you a little longer life span on your transmission as it reduces operating heat. Heat is the biggest killer of a transmission.
That’s a money save right there.

 

[No Tyme]

With my 5.3 Silverado the Black Bear tune improved the trans shifting but not much on the mpg front. Since I sold it and went back to an Avalanche with 5.3 I don't see a need for a tune. I improved my mpg's with an AEM dry filter and cleaning of the maf sensor. Went from 15.3 to mid to high 16's. I just think for a 6,000 pound sled that's not bad. Oh, I run 89 octane because of the 9.5 compression.

 

[jwth]

I have a completely stock 5.3L Flex-fuel engine in a Yukon XL. 4l60E & 4.10 gears.

Currently getting around 15-16 mpg. We do a lot of travelling, including interstate. It's not unusual for my cruising RPM to be around 2300-2500 depending on how much I'm pushing my speed. I think that's cutting into highway mileage.

I plan to keep the vehicle for years to come and I plan to keep it as stock as possible in regards to cosmetic & performance mods. But I can't help but wonder if a tune will pay for itself with improved fuel-economy. I don't care 1 bit about performance enhancements etc, it's our family car and I want to shave a bit off the fuel budget. IE, we're on-track to put 25,000 miles on it this year. Even 1 mpg improvement yields about 100 gallons of fuel saved in a year; @ $3/gal that's $300. 2+ mpg improvement pays for a tune the first year...

I know the temptation from most is to say "get the tune" because many here like them for added performance. But realistically, my only consideration is financial cost and potential reduced engine longevity (does a tune for economy just lean the engine out at cruising

 

[jwth]

I am running a custom tune on a 5.3 4x4 Yukon and run at 24 mpg more or less on the highway. It does drop to 22 when running in AWD in the winter.
Good from 45 mph up to 80 mph.
I have been running it for 1 1/2 years so it is no fluke.
No I did not buy the tune. It is a private one.