What are ya'll getting for mpg?

[aaronb]

Mine has been tuned by a local performance shop.had them correct the Speedo when they did it.

 

[90halfton]

how is everyone with "non" stock tires figuring their mileage? are you factoring in the % change in the speedo from stock?

my '98 rcsb, 5.7 w/170K, 4L60, 3.42'sand stock 265/75-16 was getting 12.5-13 highway at 74 mph.....8-10 in the city proper. i pass everything i can at WOT.

after i blew all that up i now have the GM Performance HT383E(w/ Voltant AB, JBA shorties, Magflo non CA cats and JBA single cat back), 4L70, 3.42 and 265/70-17 Duratracs getting 12.5-13.5 highway at 74 mph.....city driving is around 10. i should try it @ 65, but i'm impatient.

when i tune it i'm sure the fuel economy will go up.......as will the power.

i have a tonneau cover too.

After gear swap I had to solder jumpers in cluster.

 

[5spd Z71]

1995 K1500, 350 TBI, 35's 4.56 gears with a NV3500... I'll get 12-13 mpg. Doesn't matter if it's city or straight highway. 90% of the time I'll get 13's.

 

[Black_cirrus]

how is everyone with "non" stock tires figuring their mileage? are you factoring in the % change in the speedo from stock?

my '98 rcsb, 5.7 w/170K, 4L60, 3.42'sand stock 265/75-16 was getting 12.5-13 highway at 74 mph.....8-10 in the city proper. i pass everything i can at WOT.

after i blew all that up i now have the GM Performance HT383E(w/ Voltant AB, JBA shorties, Magflo non CA cats and JBA single cat back), 4L70, 3.42 and 265/70-17 Duratracs getting 12.5-13.5 highway at 74 mph.....city driving is around 10. i should try it @ 65, but i'm impatient.

Funny thing My burb has TBI 454/4L80 with 4:10's and I put on 285/70/17s and with the conversion was mid 7's, stock tires 245/75/16 was 9. (it goes up about 1.5 mpg or so when my wife isn't commuting 5 miles in it...) I got a drac from the junkyard pulled up the converter and a 245/75-16 with 3:73 drac is set about as close as I could get it. All my math was backed up with gps speedo check.

More to this post I drove a 97 RCLB 350 4:10 truck for work a few years ago and it got at most 12 at least 10.8, no matter how I drove or with a small trailer.
The 94 K1500 ecsb gets 12.5-14 most the time. With canopy or soft toneau cover. It got high 15's with no cat or 02 sensor highway at 70 with motorcycle on a small trailer (probably under 800lbs bike and trailer)

 

[shovelbill]

Funny thing My burb has TBI 454/4L80 with 4:10's and I put on 285/70/17s and with the conversion was mid 7's, stock tires 245/75/16 was 9. (it goes up about 1.5 mpg or so when my wife isn't commuting 5 miles in it...) I got a drac from the junkyard pulled up the converter and a 245/75-16 with 3:73 drac is set about as close as I could get it. All my math was backed up with gps speedo check.

More to this post I drove a 97 RCLB 350 4:10 truck for work a few years ago and it got at most 12 at least 10.8, no matter how I drove or with a small trailer.
The 94 K1500 ecsb gets 12.5-14 most the time. With canopy or soft toneau cover. It got high 15's with no cat or 02 sensor highway at 70 with motorcycle on a small trailer (probably under 800lbs bike and trailer)

my last rig, a bone stock 1990 K /5, sans the Flowmaster single side cat back, had TBI 350, 3.73's and 31x10.5 Cooper AT/3's. she got 7-8 city and 12 highway @ 74 mph....had 180K on the clock and burnt no oil......just a ponderous pig, LOL.

 

[cemeteryxgates45]

93 k2500 suburban 1 ton, 245/75r16E, 4.10, 350/4l80e getting 15-16 mpg on a good day 10-12 on a bad day, plow on/off, around 400 miles a tank (42 gallons but we fit 46 in it)

Sent from my E6790TM using Tapatalk

 

[Ironhead]

I have never checked the mileage on my 98 5.7, 4L60E, 3.73, stock tires. I figure I have to drive, so I have to have gas, and "it is what it is", a truck, not an economy car. Knowing the mileage, especially around the city, would be depressing.

 

[shovelbill]

After gear swap I had to solder jumpers in cluster.

i don't understand this....would you explain please?

 

[90halfton]

i don't understand this....would you explain please?

In an 88 to 94ish ( I guess ) the change of any type of drive line ratio change has to be addressed in the back of the gauge cluster. There are like, .02 amp fuses and from the factory depending on tire size, gears, whatever, they pop the fuses they don't want for the proper jumpers to still have proper continuity. There is a chart somewhere for which fuses you want for tire and gears. Simply have to pull cluster and cut out unwanted fuses and solder in jumpers where you want or solder in dipswitches for easy change later on. New vehicles you can just plug in a Doo dad and push a button.

 

[df2x4]

In an 88 to 94ish ( I guess ) the change of any type of drive line ratio change has to be addressed in the back of the gauge cluster. There are like, .02 amp fuses and from the factory depending on tire size, gears, whatever, they pop the fuses they don't want for the proper jumpers to still have proper continuity. There is a chart somewhere for which fuses you want for tire and gears. Simply have to pull cluster and cut out unwanted fuses and solder in jumpers where you want or solder in dipswitches for easy change later on. New vehicles you can just plug in a Doo dad and push a button.

You're talking about the equivalent of the DRAC, right? From what I can see in this thread, only 88-91 trucks have the electronics built into the cluster. 92-95 have the external DRAC, 96+ is all computer controlled.

http://www.gmt400.com/threads/gm-drac-vssb.31169/