Engine/Transmission (1998.5 - 2002) Real world MPG improvement

[SS]

I decided to see how much I could improve my fuel economy purely through driving habits. By my signature my truck is not the best for fuel economy -4x4, 4. 10 gears, tires, lift, bumper, etc. , but it's not the worst either - manual trans, 2500, running empty. I know that some trucks don't do as well as others, but here's my experience.



Previous 4 tanks (calculated by hand, speedometer verified): 17. 14, 16. 57, 16. 62, 15. 78 - 1,873 miles and 113. 419 gallons equalling 16. 52 mpg over that period.

Last tank: 19. 51 mpg



Same route driving the speed limit, shifting at 1500 RPM, VERY easy on the throttle. Just by doing this I increased fuel economy by 18%. For the record it about killed me trying NOT to use the smoke pedal. I have no doubt that some trucks can get into the mid 20's and I'm baffled by guys who call anyone who claims that they do a liar.



Anyway, these are my observations if you are interested.

 

[darkhorse]

For the record it about killed me trying NOT to use the smoke pedal. I have no doubt that some trucks can get into the mid 20's and I'm baffled by guys who call anyone who claims that they do a liar.



Anyway, these are my observations if you are interested.

I second your experience. When I'm being really good I can nurse 25 mpg out of my truck. That's a steady cc 65 mph & no over 10 psi accelerations. Not easy to do. "Normal" daily driving gets me closer to 18 mpg.

 

[hemijustin]

my speedo is way off... but i used my gps and i got like 12 miles to the gallon. but then i cant keep my foot out of it. i get the same towing my trailer as i do regular driving. but then i usaly dont go over 75 with my trailer eather. and i usaly run around 85 out on the road. were can i get my spedo recalibrated?

 

[RStacy]

I decided to see how much I could improve my fuel economy purely through driving habits. By my signature my truck is not the best for fuel economy -4x4, 4. 10 gears, tires, lift, bumper, etc. , but it's not the worst either - manual trans, 2500, running empty. I know that some trucks don't do as well as others, but here's my experience.



Previous 4 tanks (calculated by hand, speedometer verified): 17. 14, 16. 57, 16. 62, 15. 78 - 1,873 miles and 113. 419 gallons equalling 16. 52 mpg over that period.

Last tank: 19. 51 mpg



Same route driving the speed limit, shifting at 1500 RPM, VERY easy on the throttle. Just by doing this I increased fuel economy by 18%. For the record it about killed me trying NOT to use the smoke pedal. I have no doubt that some trucks can get into the mid 20's and I'm baffled by guys who call anyone who claims that they do a liar.



Anyway, these are my observations if you are interested.

I like your post. I got 22-24mpg on the interstate keeping it under 70mph. at 70mph i was down to 19 +/-. Then I put the 305's on and went down 21 as an all time high so far. will be going to charlotte nc this weekend (about 2 hours) and i'll check it again. By the way, did I mention that with me and the tools that stay in the truck (everyday work tools) that we (my truck and I) weigh in at 8250 lbs. checked the scales the other day! So with roughly 800 lbs in tools in the bed, I can drop 16 mpg in town. (with easy driving) normally I come in AROUND 14-15 though. with the ac and a heavy foot!!! I don't think I ever went below 12. Well not counting when the hub assebly was hanging on by one bolt. Oh yeah my truck just turned 229,xxx on the clock. Looking for a VP! (I don't have all the luck)

 

[Cummins Thunder]

Best I have ever seen was 16. 9 MPG Steady 75mph on I-10



I get around 12-14 day to day... Kind of makes me want a 2wd SRW

 

[JRihani]

I'm also looking to improve MPG but I have a potentially good setup to do so (see sig).



My best hand-calculated tank was the first full tank I ever put in the truck... long interstate trip. 23. 34 MPG. I commute about 60 miles round-trip everyday mostly going 60mph on a combination of highways around Indianapolis. I've never recorded less than 20mpg in the past 2,700 miles put on the truck, all hand-calculated.



I'm about to put a full A. R. E. topper on the bed and am looking forward to seeing what that does. I'm also about to switch to Royal Purple synthetic tip-to-tail... interesting to see if that does anything



Keep us posted on MPG improvements!

 

[terrywerm]

I used to get a maximum of 18 during the summer, but that was with 285's with a mud tread. Ever since switching to 265/E's with a much more civilized tread, my mileage came up to 20 to 21 on a daily basis. I typically drive 52 miles per day, round trip to work and back, about 50/50 for street / highway.



If I behave myself and step softly on the pedal, I can pull the mileage up to 23, but it is pretty tough to NOT use the power available when you KNOW it's there. Truck hasn't been bombed yet, but it is on the horizon, planning to upgrade the clutch, then add Mach 1. 6 sticks and Marco's ECM. I know I'll get some added power, but I just hope I can keep my foot out of it enough to keep the mileage up!



Oh, I almost forgot: My son has a Chevy S-10 with the 2. 2L in it with a manual trans - he's only getting 18-19 MPG. Granted, he might be a little heavy with the right foot though.

 

[trqmnstr]

Yeah, I once posted that I got 24. 7mpg on the highway and had a few members tell me that was impossible. They said I must have figured it wrong because they only got 16 or 18. The next day or so, there was a MPG thread and everybody that posted got between 20-26 mpg. Call me a liar now.

 

[bkroupa]

I was skeptical of some of the MPG claims, before I bought mine. With 4. 10's & 245 tires mine averaged 19mpg cruising 70-75 on the trip home from Alabama where I bought it. I went to 285 tires & my average mpg increased by ~. 2, I had the timing bumped to 16 & it jumped to 21 summer running A/C & 21. 5 during out very mild winters. I swapped out the 4. 10's for 3. 54's & my last 4 tanks have been above 22. 6 with a best of 22. 99 (made a run from Freeport to Huntsville & back driving 70-75 mph on that tank in addition to my regular drive).

My commute is mostly 65 mph hwy speeds 120 miles a day. I fill up at the same place most of the time & fill to a visible level each time. I have no doubt that people without tow mirrors/clearance lights & tires with less rolling resistance can get 24mpg+ on a trip.

BTW the exhaust, BHAF & tonneau cover didn't show any mpg gains at all for my normal drive. I did notice a little less mpg penalty for going 70 & faster with the cover on.

 

[CumminsFarmer]

Best I got was 22 mpg on the way home when I bought the rig. Since then Ive done the mods listed below, and put 285/75 tires on. Best I get now is 20, 18 normal city, and 17 on the gravel roads out to the farm. I dont have a computer chip, which Im told tweaks for performance. The 'stage 2 injectors' are stock injectors that have been hydraulically honed to improve injection patterns. Added roughly 80-90 horsepower, but obviously does nothing for computer performance. Any input on the chips?