You just need a bigger gas tank! I can make 500-550 on my tank! I run between 11 and 13 with my 7.4 unless I'm towing. 400 mile trip with 9000 lbs through mountains and I'm still at a solid 9. Not a single complaint over here from me. My wife isn't too happy about the $120 fill up every week!
M.P.G. question
- Thread starter Jack Schneider
- Start date
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96 K1500 305 5.0L 6” 35 12.50 15 3.73
And I avg 14-14.5 daily commuting. 17 miles. 10 highway @ 60-65 7 miles in town stop and go. Best of 15.5 mpg. Best was to work and back only while going fishing and back and forth to the gym it’s typically 14.1-14.5 every time. I don’t drive it hard, but every once in a while.
Mods are vortec box delete, throttle body mod, shorty headers, 2.25 y pipe, 3” exhaust, ls1 fans, 170 t stat, 89 tune.
Here is my mpg as the mods were added
100% stock with 35s it got 14.1 best avg 11
Shorty headers added no change best but 11.5-12 mpg avg
89 octane PCM for less tune best of 14.4 mpg but avg was 12.5
Built a custom 2.25 y pipe to connect to 3” exhaust and avg 13 best of 14.4 still
Added ls1 e fans and a 180 t stat and avg is now 14.0-14.5 with a best of 15.5.
From stock to now she runs night and day difference and as you can see the mpg improved quite well.
And I avg 14-14.5 daily commuting. 17 miles. 10 highway @ 60-65 7 miles in town stop and go. Best of 15.5 mpg. Best was to work and back only while going fishing and back and forth to the gym it’s typically 14.1-14.5 every time. I don’t drive it hard, but every once in a while.
Mods are vortec box delete, throttle body mod, shorty headers, 2.25 y pipe, 3” exhaust, ls1 fans, 170 t stat, 89 tune.
Here is my mpg as the mods were added
100% stock with 35s it got 14.1 best avg 11
Shorty headers added no change best but 11.5-12 mpg avg
89 octane PCM for less tune best of 14.4 mpg but avg was 12.5
Built a custom 2.25 y pipe to connect to 3” exhaust and avg 13 best of 14.4 still
Added ls1 e fans and a 180 t stat and avg is now 14.0-14.5 with a best of 15.5.
From stock to now she runs night and day difference and as you can see the mpg improved quite well.
L31MaxExpress
I'm Awesome
^^^Didn't you know that 180*F thermostat is running your engine too cool and killing your MPG!^^^
Complete and total sarcasm by the way from people who believe everything the hear and have not tested it themselves.
Not trying to start BS, but maybe He doesnt know. Explain how a lower temp thermostat kills fuel millage.
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Oldblue98
I'm Awesome
I have Hypertech tuning for mine, and I did exactly what you are talking about. I went back to 195 degree and put all settings back to stock. And brought mileage back to a consistent 15 mpg around town. I don't know what hwy would be , my truck has not been out of town in a long time. Seems to actually run smoother !? My proof is at the pump ! I did not do this on posters say so, I did this quiet some time ago.
I'm guessing that is a slight against me, I'm so glad that your TUNED vehicles are running so well with a lower degree thermostat. You never did give any evidence that your mpg went up or down with JUST a thermostat change, just conjecture about 2-3 hp from dyno run pulls.
I have for a FACT increased my mpg by doing nothing more than changing my thermostat from a 160* to a 195* with 100% stock programming.
Again, this has been PROVEN by others not only on this forum but on LS1 tech as well.
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QUOTE="Oldblue98, post: 1021604, member: 20171"]I have Hypertech tuning for mine, and I did exactly what you are talking about. I went back to 195 degree and put all settings back to stock. And brought mileage back to a consistent 15 mpg around town. I don't know what hwy would be , my truck has not been out of town in a long time. Seems to actually run smoother !? My proof is at the pump ! I did not do this on posters say so, I did this quiet some time ago.[/QUOTE]
I mean each motor is different some like hot some like colder; just gotta find that sweet spot for them
I mean each motor is different some like hot some like colder; just gotta find that sweet spot for them
shorepatrol
I'm Awesome
I'm around 14mpg in town, 19mpg highway unloaded, 10mpg or less towing. 33's and 3:73
L31MaxExpress
I'm Awesome
You knocked me in the other post and my L31 likes running cooler. It was stock tune blacl box when I swapped the thermostat back in 2006 as well. I honestly do not see how the thermostat is hurting your MPG. Mine hurt my MPG because the engine would detonate on stock tuning and the PCM would go into low octane mode which would neuter the timing advance it had. On a 105°F day I jad ZERO power with the coolant temp at 3/4 on the factory gauge. My cooling system was in good shape at that time as well. New radiator, new fan clutch, clean condenser, etc.
First of all, I absolutely was being a cheeky **** I'm glad you picked up on that. Second of all, I never denied that your vehicle ran/runs better with a lower temp thermostat. I'm merely stating that your vehicle seems to be the exception not the rule in regards to mpg. Finally and I believe most telling of the whole situation, my truck has never sat that high on the factory coolant gauge. Not with the factory original 195* t-stat and not with this new one. My truck sits at 1-2 hashes above 1/4. It has never gone past the 1/2 mark on the gauge.
Perhaps your t-stat was fubar, in either case you have better things to do, I have better things to do. So let's just agree to disagree.
Perhaps your t-stat was fubar, in either case you have better things to do, I have better things to do. So let's just agree to disagree.
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