Better mileage ?

[RWestbrook]

2003 blackslt 3500 dually, 47re auto trans, 24 valve diesel











Since my truck has hit 10 k miles, my fuel mileage has increased 4 to 5 mpg while pulling a 10k lb. trailer every day. I havn't done anything to the truck. Is there a break in period for the new diesel?

 

[David Muench]

Yes, usually 10-15k miles.

 

[jlhartak]

A friend had a 1st Gen, he said his mileage increased until about 40K. I have 30K and seem to be getting slightly better mileage as I go along. Your truck is loaded most of the time so that might shorten break in.

 

[Parshal]

I wish this were true for mine. The only way I see better mileage with the EZ installed. With it removed, I get the same mileage I did a 1000 miles.

 

[ladyjaine]

Have you gone from winter to summer blend? That also affects miles per gallon.



Jean

 

[E7mack96]

I can't get better than 16 mpgs... Highway, or city driving, 55mph all the way to 70 mph.



I miss my 2001. It got 20 or better on a regular basis

 

[djbobo]

EMACK

I get a wopping 13. 9 mpg 50/50 city highway driving - calculated. It won't stay in overdrive going up grades to boot. 4500 miles so far. Can anybody beat those numbers?



dj

 

[ShannonPhillips]

I average 13-15 mpg with 50/50 highway vs. city. So far not to impressed.

 

[djbobo]

Shannan

I assume you've adjusted for your 35" tires. If not , I still remain 'The low number ' king. If you have . let's call it a tie.



dj

 

[ShannonPhillips]

djbobo, Unfortunately, yes I have adjusted for the 35's, I have no idea why the mileage is so poor. My interstate travel is at 65 mph, so it really stinks!



Thanks Shannon



By the way, I may give this to the wife and get me a 12 or 24 valve!

 

[RWestbrook]

Also check your tire pressure from the factory. If you are pulling a load you will need to inflate to the correct amounts. This gave me about 1. 5 mpg better.

 

[robobx]

I used to get over 20 all the time, city and highway. once I hit 11-12,000 miles it dropped. I can't hit 20 on flat highway under 60 mph now. my driving habits have not changed. I would think I should be getting better mileage now, no more winter blend, over 20,000 miles, and charlotte is damn near flat compared to pittsburgh(where I lived and got 20+mpg)

 

[jlhartak]

Robobx, You might check for a intake restriction or something fuel related. It may just be you are now in an area where the refinery blends diesel of a inferior grade to what you had in Pittsburgh. I know on long trips I have had the odd fill up that calculates several MPG less than the average of fill ups on either side of it; this doesn't seem to be related to any road/driving factors so I think it is just moving thru areas served by different refineries.

 

[MattSt]

Originally posted by E7mack96

I can't get better than 16 mpgs... Highway, or city driving, 55mph all the way to 70 mph.



I miss my 2001. It got 20 or better on a regular basis

Same for me. I actually hit 16. 1 on a 100 mile trip going 60 the whole way. My 30 mile commute to work (75 mph) is getting me 15. 2-15. 6 That's with a 6 speed and 3. 73 gears. Glad I didn't get the 4. 10's!



I'm about to throw a chip, exhaust, injectors and intake on it and at least give it an excuse for getting crappy mileage!



My old 2001 chipped would get 15 towing 10,000#'s on numerous trips in the flat lands. I just don't get it. I put the empty trailer (4800#'s)behind this pig and it's 13. nothing.

 

[Kilby]

Originally posted by djbobo

Shannan

I assume you've adjusted for your 35" tires. If not , I still remain 'The low number ' king. If you have . let's call it a tie.



dj

I only have a couple of tanks worth on mine but I'm down to 11 mpg or less. I really do hope it gets better and you still remain the low number king.

 

[THanley]

Better Mileage?

I have a 2003, 2500 SWB with the 3. 72 gears.



I usually run unloaded and get 15 to 17 around town and the following at speed:



55mph --> 24mpg

65mph --> 19mpg

75mph --> 15mph



As you can see, speed of travel has a big impact on fuel economy.

I travel in Iowa and South Dakota where it's flat for the most part.

 

[EBramwell]

I've noticed that my truck is now getting on average 16mpg unloaded twn/hwy driving, and it has 4. 10's. Now pulling one of my trailers that weighs around 10 thousand will nock it down to about 10 mpg. This is running at around 60 - 70 mph. I've got 4500 miles on it also.

 

[HBrink]

With only 734 miles on the odometer, and a bone stock 03 truck (see sig), I am getting an average of 16. 5 mpg on short commutes less than 15 miles and a couple of highway trips. I'm very pleased with the economy so far and expect some improvement after I get some time on the engine while towing my 35 foot Alpenlite trailer.



Take care,

Harry

 

[djbobo]

Kilby- you da man



I started filling up at a different station & driving under 70 & the overhead is staying steady at over 17 mpg. Cant wait to do the math in a few days.

I'm going to expeirment with additives for the fuel before my 800 mile trip this weekend to see if it won't help a bit. Let you know if anything drastic happens.

Maybe our drive trains & engines are a little tighter than most.



dj

 

[djbobo]

Kilby- you da man



I started filling up at a different station & driving under 70 & the overhead is staying steady at over 17 mpg. Cant wait to do the math in a few days.

I'm going to expeirment with additives for the fuel before my 800 mile trip this weekend to see if it won't help a bit. Let you know if anything drastic happens.

Maybe our drive trains & engines are a little tighter than most.



dj