What kind of mileage should I be looking at. We have a 1998 2500 with a 12v and 3.5 rear. Mileage is around 12mpg city or highway. Fuel and air filters are new. My mechanic says that's the way it is and there isn't anything to adjust.

Previous truck was a 1991 Dodge Cummings 2500 getting between 22 and 26 mpg regardless of load.

TIA

BeemerBob

 

I get that because I drive in town alot. Is your truck stock? Do you drive alot in town? Welcome and please fill in your sig so we know what you have.

 

Do you let you truck warm up for long periods of time?

 

I am modded with about the least efficient injectors that I could put in my truck; 370s. I get about 15 around town, and 19 highway. I drive like a madman. there is definately something wrong with your truck. do you have an auto or manual?

 

My mileage is about 10-12mpg in the city. Maybe 16 on the highway. Thats with the upgraded convertor and a new lift pump and overflow valve. Im guessing my pump is worn a bit since thats the only thing left. Another odd symptom I get now is fuel pressure that fluctuates a bit and a dip down to as low as 10psi at WOT.

 

Sorry about the lapse in specifics. This is a 1998 Dodge 2500 12V with a 3.5 rear. It is a stock truck, nothing fancy no upgrades, it's just a truck, my wife's to be clear. She uses it around town, rural driving and hauling her horses around in her gooseneck.

The oil filter was changed out a month ago as was the air filter. We are just miffed that the mileage isn't anywhere near what we had with her previous Dodge (1991 2500 Cummings, stock). THat puppy got between 22 and 26 mpg regardless of what we were doing.

BeemerBob

1998 2500 12 V stock 3.5 rear.
How's that???

 

Alright thank you. If she is driving in town all the time then I don't believe it will get any better, but then again I could be wrong. I drive mine in town 6 days a week and the most I have ever seen on mine is 12.69.If I drive the highway a few times a week I might make 14.

 

I used to have a truck with a auto and 3.55's, and it got 21 mpg average. The truck I have now is auto with 4.10's and I am getting about 17 average. Both were/are stock 12 v's. I think you should be doing alot better since you have the 3.55's.

 

Id look for problems with fuel pressure, timing, loose torque convertor, dragging brakes, clogged injectors.
Seems to me that the lower HP pumps get worse mileage. I wonder if a 215 runs higher pressures than the 160 as well as more volume?

 

I get 17 to 17.5 around town with my mods.
You of course have checked for leaks? Any smoke at exhaust? Timing ?Maybe lose the Cat.?
Seems to me you should be doing better. Might as well put some performance stuff on , may help.

 

Not meaning to jump on but; the first thing I would check is the timing. My 97 3/4 with a few up grades gets 17-21 no matter what. The timing doen't cost much and will enhance performance if not improving mileage.

 

im at 16mpg town.

20.5 mpg highway.

i've rolled out 700 miles on a long all highway trip one time to PA before the fuel light came on.

 

Check my bio 12 in town 17.7 hwy duelly

 

I'm also gonna suggest having the timing bumped, or doing it yourself. I would go to at least 15* More would be better for milage, but would hurt low end a bit much for a stock truck that tows.

 

pump timing or ignition?
or both?

im looking for better mileage... im getting about 16.2 right now, not towing.