GAS Mileage - how to make it better.

[dr_of_lovephd]

Well, I filled the tank tonight for the first time since the trip I mentioned earlier and my actual mileage was 20.5 mpg. Its not as good as the 21.7, but still pretty good. All told, I went 373 miles on 18 gallons. I guess the dic is fairly accurate but not exact.

[dcarson]

I am envious of all you guys. I get right around 12mpg give or take a half. 2500 4x4 with 6.0, and it can pull into a gas station all by itself. Gas does make a difference though. I will not let any vehicle in my family be filled up with generic gas. BP, Amoco, Citgo, Exxon, or Texaco for us, and primarily Amoco and Exxon. I had too many old carbs rebuilt because of bad gas.

[White Lightening]

Originally Posted by dcarson

I am envious of all you guys. I get right around 12mpg give or take a half. 2500 4x4 with 6.0, and it can pull into a gas station all by itself. Gas does make a difference though. I will not let any vehicle in my family be filled up with generic gas. BP, Amoco, Citgo, Exxon, or Texaco for us, and primarily Amoco and Exxon. I had too many old carbs rebuilt because of bad gas.

Greetings DCarson,

No need to be envious - every vehicle has its purpose. I have a good friend who advised me not to get the Chevy truck I ended up getting - if gas mileage was a concern for me. He has a 2003 2500 4x4 std cab long bed with the 6.0 and he claimed at the time that he never ever got more than 13, usually it was 12 or so. When I got my truck, he was a bit frustrated that I was getting so much better mileage than he was - so I bet him I could increase his by 15% and we'd measure it AFTER two tankfuls of gas had been run thru - then the third one was the measurement. Did it. Ended up just under 16 - and he was both happy it could be done - and ticked that he lost the bet to me :-)

White Lightening

[dcarson]

well then don't be a darn tease. How did you do it?

[White Lightening]

Originally Posted by dcarson

well then don't be a darn tease. How did you do it?

Greetings DCarson,

It was a series of things:
1. Ran the gas down to low level - then required specific gas station fillups (to assure good gas).
2. First tank of gas - use one of the cheap fuel cleaners (plastic bottle)
3. Second tank of gas - use good fuel cleaner in an aluminum can (I used Slick 50)

Reasoning to this point - first tank had to soften any accumulated crud in the fuel system (injectors etc.) - then the "real" one (Slick 50 version) is free to do its thing.

4. Tire pressure - all 4 tires.
5. Had someone check/inspect wheel bearings and pack/lubricate if needed.
6. Required driver to keep tailgate down on highway (to simulate a tonneau cover or cap to improve wind resistance).
7. Changed out air filter.
8. Did an oil change and used Slick 50 oil additive.
9. Washed and waxed the truck.
10. The "measurement" tank of fuel was the third tank of gas. He drove a highway route that he often drives but the rule was - no driving faster than the speed limit. Normally he gets about 12 to 13 mpg on this trip - instead he got just a hair less than 16.

For reference - 2500 HD 4x4, 6 liter V8 gas, 8 foot box, standard cab 2003 model.

Note: I recommended he switch to a FRAM Air Hog air filter instead of standard - but he didn't want to spend the money on it.

Note: He drives fast - my guess is had I been driving instead - we'd have kept that speed limit rule "a little tighter" and probably gotten to nearly 17.

White Lightening

[rabt]

i have a 2001 ext cab short bed with the 4.8 V8 and get 19 city 24.5 hwy
i also have a 2004 reg cab long bed 4.3 V6 company truck that i get 14 city 15 hwy

the V6's have to work way to hard to pull around these full size trucks ... that is my guess on the gas millage

[dcarson]

White litnin'
sounds about like me. I bought the truck used, so first thing I did is have a thorough service. That actually included buying new set of bfg's, run three tanks of premium gas with red line total system fuel cleaner in the first one, and chevron in the next two. I also run a bottle of fuel cleaner in about every third tank of gas. Oil was changed when I got the truck, and again in another 1500 miles just to check everything out. My truck has to stay washed and waxed because I have an aircraft detailing company and it looks bad if my stuff is dirty. Actually waxed with a straight teflon sealant. I need to keep the tailgate down more often. I do whenever I can, but I often forget. I have a new purolator air filter in, but am planning to switch to eithr a kn, green, or one of the new sponge racing filters.

1999 2500 4x4 6.0 ext cab. I am getting 12 and on the hwy with gate down can get about 13.5 I have started driving my nissan more now.

[White Lightening]

Greetings,

I didn't want to get off on a different subject with this thread - however I did have a question about which grade of gas to use for my truck. If anyone has an opinion - I'm all ears at the following thread.

http://www.automotiveforums.com/vbul...d.php?t=353128

White Lightening

[ryanszpara]

i got like 18 MPG this last weekend in my 02 5.3L doin like 90-95 the whole 4 hours.....also found my Govenor at around 99 mph.......

[silveradoking]

i get a bit more than 22 mpg. i got a 5.3 v8. i change my oild with mobil 1 with a kn filter, every 4000 kilometres, sorry guys i am in canada. my diffs have always used the royal purples max gear oil which gives it more horsepower and better mileage. i recently changed my trans oil, also royal purple and installed a oil cooler and a 3 quart pan from b&m, this gave it a smoother shift and it kinda feels like i have more horses under the hood. i have a kn filk kit installed, for better air flow. plus a soft tonneau cover which really helped me out. all in all when i bought the truck it wasn't good, i have had many problems with it, probably close to everyone listed in this forum but i love this truck.... it's is all in the matter of how you guys take care of it, and how you drive it...

[White Lightening]

Originally Posted by silveradoking

i get a bit more than 22 mpg. i got a 5.3 v8. i change my oild with mobil 1 with a kn filter, every 4000 kilometres, sorry guys i am in canada. my diffs have always used the royal purples max gear oil which gives it more horsepower and better mileage. i recently changed my trans oil, also royal purple and installed a oil cooler and a 3 quart pan from b&m, this gave it a smoother shift and it kinda feels like i have more horses under the hood. i have a kn filk kit installed, for better air flow. plus a soft tonneau cover which really helped me out. all in all when i bought the truck it wasn't good, i have had many problems with it, probably close to everyone listed in this forum but i love this truck.... it's is all in the matter of how you guys take care of it, and how you drive it...

Greetings Silverdoking,

I'm curious. It sounds from your post, like you have put Royal Purple in your differential and also plan on putting it in your transmission.

My understanding is that for Royal Purple to be used - you have to eliminate the prior oil based product so there is no contamination etc.. Tranmissions are difficult to understand how you could purge the past regular trans fluid - because dropping the pan doesn't eliminate a good percentage still in the transmission. So how do you get the fluid ALL out of entire transmission system. And I would think purging the diffential fluid would be similarly difficult. I'm considering doing what you did but I can't figure out how to get it switched out without diluting the Royal purple with the original fluids (or contaminating the performance of the expensive Royal Purple product).

1. What was your procedure for each?
2. What kinds of costs did you spend to accomplish it?
3. What kinds of benefits or improvements did you notice?

White Lightening

[silveradoman]

Maybe on the rear end I would flush it with diesel, but then wouldn´t the royal purple get contaminated with the diesel? do you flush out the diesel with gasoline and let evaporate?? hmm...

[silveradoking]

Just for your information..... When I changed my rear diff for example, I drained the fluid, then took the cover off, cleaned up, put a new gasket.... and put cover back... I then filled with the royal purple....now because it is just about 2 in a half quarts, I did not buy any cheaper fluid( I'll explain later). I put the royal purple in, then drove for about 50 kilometres, drained again the fluid and filled it again with royal purple.... I will change it again in 20, 000 kilometres, since I like to take care of it so much....the rear diff cost me about 5 quarts- $60.00 bucks canadian, and the gasket cost about $15.00. Almost the same for the front diff, minus the gasket..... For the transmission fluid it was a little more expensive, or a lot more.... but I feel with the improvements and money that I have spent is well worth it... I believe that my transmission will last me for a VERY, VERY, VERY, long time....I drained the pan, replaced filter.... At this point I was debating whether to flush it out, or not but with all the stories I have heard I decided to stick with my plan.... I also changed those little, dawm pieces of plastic... then put pan back... and filled with some cheap transmission fluid, as long as ut's new it doesn't matter... 5 quarts.... drove for a little while and did the same again... drop pan, change filter again... and out 5 more quarts cheap fluid.... drove a while.... and then only drained the fluid, the fluid this time..... I did this one more time... for a total of 20 quarts cheap fluid and two filters.... now the good part drain again.. this time fill with royal purple....I did this 5 times, and the last time using a brand new filter.... it cost me 3 filters--- $30.00 bucks each = $90.00 + 20 quarts cheap fluid $30.00 + 25 quarts royal purple.... I think it cost me around $210.00 Grand Total---$330. 00
I also added a transmission cooler, and the B&M pan for $200.00 ..... yes, it was expensive but well worth it.... now I will keep changing it every 30,000 kilometres... so it better dawm last me forever... I hope.....

[silveradoking]

I forgot to tell you that there was definately a performance inprovement, GAURANTEED smoother shifts.... I was very impressed... That is why I switched almost every thing to Royal Purple, just don't change your transfer case fluid to Royal Purple, actually there is no specificcally made for transfer case fluid from royal purple.. but the syncromax is supposed to go there..... but don't do it.... Auto Trac II is the only fluid for these trucks.... sorry for the long post.....

[silveradoking]

One more... that is the only way I could think about changing these fluids.... I did this all within my abilties....so I hope that the money, time, and care make this truck last forever??????? But I recommend that you change the rear diff at least to royal purple.... you can actually feel the difference, more horsepower thats for sure....