01 extended cab 4x4 off road,5.9 with 36k miles i get 10-11 drivin easy. this is calculated at the pump i dont go by the overhead gauges. this is all around town driving i dont do any highway. truck is stock except for 285/70/17 bfg all terrain tires. after i installed these tires i though for sure my milage would drop but it did not.

 

I got a 01' 1500 Sport Ext Cab 4x4 with 5.9L, 3.55 gears, auto. Cold air intake, 2.5" machine bent duals with magnaflow muffler, and tonneau cover. On just highway I av. about 15. City varies from 12-14 depending how hard I drive. Got 15.9 once. Oh ya, the overhead computer isn't always correct. I check the mileage myself.

 

I just got my 96 2500 xtra cab short box, stock tire size added a K&N air filter my first three tanks of gas are as follows. mostly city, and some 4x4 15.25 mpg ; 50/50 city hwy 16.6 mpg and last tank was 100% hwy using cruise control to maintain a constant 100 kph and I got 18.8 mpg

 

ive got a 98 1500 reg cab, long bed and i get 10-11. All i have added is a heartthrob cat back dual exhaust. This is all city driving too with some off roading.

 

I have esentially the same truck with no mods. Do you thing the cold air intake and/or the duals helped much?

 

I think the exhaust helped on low end. It is a magnaflow which is quiter than what I wanted but didn't realized it until after it was done and wasn't paying to change it. The CAI is a cheap one from e-bay I got for $52. It came with a too long of S-bolt but I got another one from a friend that works. It does allow more air flow as I can hear it sucking the air and helped throttle response. I still need to build a heat shield though and I think that would help. As to the mileage when I first got the truck the best it would do is 15 driving on the highway. With the CAI and exhuast I get about 15 driving back and forth to work which is some stop and go but no real big cities. I have gotten 15.9 on the highway once after the mods. I am hoping to find out some more results from others about the fastman tb and may consider that.

 

Well when Dan called me from Fastman he said I can expect a 4-5 mPG increase on my 99 5.9 Sport 4x4, that may get me 11-12-13 mpg, I replaced O2 sensors put new plugs in and put a twister high flow exhaust (keeping my mandrels) as for CAI my verdict is still out on those I think i get cooler air from my fender well than inside the motor, i may attempt to build one of my own coming from the fender, I may even go for the patent, after the throttle body i have no idea what else to do, increase my spark, that still doesnt do anything about the fuel being dumped in,If your plugs are gray and nicely burnt I cant see improving a spark, I just think there isnt much ways around the gas guzzlers

 

Has anyone out there tried a Jacobs ignition setup? They make some pretty strong claims and I have seen an article or to to back them up, only it was with points ignition.

 

Oh murcy charlie you sound like me on the distance you travel and the town's spacing apart... I've not calculated anything as yet but I have a 98 Dodge Ram 1500 with a 4tech5 muffler and just the standard 5.9L 360 engine in mine and I fill up once a week and travel to and from work 4 out of 5 days and only use a half of a tank of gas and I travel 25 miles one way... so I'm guessing I get pretty good mpg's... who knows maybe not...lol

 

I hate to be an *** but your way of checking mileage don't mean ****! Guessing about how many miles you drive and saying you use about a half tank of gas is a bunch of crap. The guage can vary slighty and could be misinterpreted by a gallon or two which makes a big difference in such a small calculation. It also depends if you have a short bed or long bed because they have different size tanks I believe. The only accurate way to check is fill up, reset the trip meter and the next time you fill up divide the miles by the gallons.