I have heard of great MPG's on this forum (18-20 mpg) and no matter what I have done to mine, I can't get above 14. So I started thinking maybe we are not comparing apples to apples. I can believe that a standard truck will get better mileage, as well as a two wheel drive with a short bed. So this is what I have and I would be interested to hear from others with the same set up what kind of mileage you get.

1998 4 wheel drive with an automatic. Long bed. Extended Cab. Completely stock.
Thanks

 

My 1997 is the same truck as your 98 if its a 12V. I just got 17mpg on a recent 300 mile trip. It was mostly two lane roads, mostly flat with a few hills, speed limits were 65, I set the cruise on 73 and passed everything else in my way. Previous owner was a family member and said they had recorded as high as 20-22. His foot may be a bit lighter than mine.

What have you done to yours? Air and Fuel filter clean? Is yours a 3.54 or a 4.10 axle? How many miles on it? I've read where some of the cats can plug up causing lower performance and mileage as well.

 

It only has 71k original on it. I will have to check on the rear end. As I mentioned, it is completely original. I only put around 2-3k on it a year. Each year I start out with new oil and filters. I will find the rear end ratio and post it. Thanks

 

My axle is listed on a sticker on the underside of the hood. You can also request a complete build sheet with everything the truck was equipped with from Dodge.

 

I was getting 17MPG at 70MPH....I haven't checked for a while,but I think it may have gone down.But not sure.Not sure if running LC will cut my milage down.

 

I have ( had ) a 97 Ext. cab 4X4 Automatic truck that got good mileage. Since July I have been tracking each tank religiously.

Never got less than 15.5 all city, high of 21.76 mostly highway.

There was an event starting late Nov that took it down to 13.6 pretty consistently. At first I thought it was winter fuel, but I have done some hwy runs that should have brought it back up some, and the best to date is a 14.1 MPG tank.

I am working through things one step at a time to see where I lost it. I have noticed my lift pump ticking, and am in the process of gathering parts for a fuel pressure gauge.

So it is possible to get that mileage, and equally as possible to lose it. Now we just have to figure out where the heck it went.

 

I too have a 97 ext. cab long box 4x4 with an automatic. I bought the truck last April with 118k on it - and it now has approx. 128k. Until 2 months ago it had 4.10 gears with 265/75/16 tires AT tires. I averaged approx. 15 mpg including some towing and a lot of empty driving. The worst was 11.9 towing my Jeep with a slide in camper - the best was 17.8 empty driving to my cabin.

At the end of November I swapped in 3.55 gears to try to get better mileage. The day I did the swap it snowed 8 inches - and it has been really cold and snowy since then making it very hard to get a decent number but I am hoping for a consistent 2 mpg better with the new gears. I haven't driven it too much since I have a beater Honda Accord that gets 28 mpg and warms up a lot quicker! Hope this helps.

 

My truck is the same as yours except I have a 5spd. I have 245/75/16's on it with a 3.55 rear. The key to mileage for me is keeping my speed down so I stick to 65 on the highway. If I stick to mostly highway, I get 21-22 consistently. Since I rarely actually have real traffic, the empty mileage almost never goes below 20. The worst mileage I have ever gotten was 12mpg while towing a high windage trailer into a huge headwind.

 

With the 3500 in my sig. I regularly got 14mpg- I know its a 24v, but 4.10's and 35in tires on a dually didn't help.

My 96 2500 with skinny tires and 3.54 gears, worst of 17.8 - best of 22.3.

Admittingly I drove the dually a bit more aggresively, but even when I drove conservatively (slow starts and speed limit) best I would do is 16ish.

These are all hand calculations with speedometer adjusted for tire size.

 

I get about 16 in town and on the highway. The best I got was 20 mpg on a trip to SC driving a lot of back roads. I am converting to run on wvo. I was going to swap gears from 4.10 to 3.55, but I like how the 4.10s drive.

 

I just checked and found that I have the 3.54 gears. Thank you for all your responses. Sooner or later I will find the culpret to my low mpg. My truck only has 71K on it so I know it is not worn out.

 

When I first got my truck I couldn't get better than 12-13 mpg. After I learned to drive it I got up to 14-15. Then I regear'd it (4.10 to 3.54) and my milage went up to 16 all the time. Then since I fixed a few fueling issues and I'm getting mid 17's. My hope is when I finally get around to bumping my timing it will bring it up to 19 and maybe 20 with some new injectors.

1997 3500 DRW club cab 4x4 5 speed limited slip diff 159,000 miles.



samahi72:
What I would suggest for you is completly go through your fuel system (replace the folowing.... fuel filter, overflow valve, strainer, fuel heater, rubber lines from motor to frame, ect...) Lots of this stuff goes bad on these truck with just age... Then get yourself a BHAF (big honkin air filter). Then either staight pipe or get and exhaust system. Then have your timing verified and maybe bumped to 15-16..... I bet you pick up between 2-6 mpg with that stuff alone

 

That gives me some place to start. Here in Colorado we have to have the Cat Convertor so I am not sure how much good eliminating the muffler will do.

 

Go through the fuel system, and get the timing bumped for sure. My 95 still has the original exhaust intact, and stock timing, and with a plate and stage 1 injectors I get 17.7 mpg consistent. It's only a 160 pump in comparison to your 180 though.

Upgraded torque converter and valve body will do wonders for getting all the power to the ground and increase mpg.

Everything I've mentioned is stuff that is going to get done to my 95.

 

I average 17-18 out of mine when I go easy, I did get 20.4 with it once but I have this little problem with my right foot that just kills my economy