Tips needed for eco-driving my diesel truck! - Fuel Economy, Hypermiling, EcoModding News and Forum

nubbzcummins · 12-25-2009, 11:08 PM

Quick specs: 06 dodge ram 2500 4x4, 5.9l turbo diesel, 2.5" lift in front to level, 4 spd auto with o/d, cruise control, 3.73 gears, 325/55r22 tires, intake, exhaust, programmer. Tranny has 3 modes: Normal, tow/haul, and o/d off. Normal will make shifts at higher rpms and only lock t/c in o/d at lowest speed of 57mph however if cruise control is on you can maintain locked t/c as low as 1000rpm and around 41mph. Tow/haul makes shifts around 100-200rpm sooner than normal, runs higher fluid pressure in tranny, locks t/c when shifting to 3rd at 34mph and o/d at 53mph. Can go as slow as 28mph in 3rd and 49mph in o/d before the t/c will unlock. O/d off operates like normal except no o/d.

Normal driving conditions: Drive approx 140 miles/day mostly highway with some city driving and probly a dozen traffic lights to deal with. Highway has 45-55mph max and city 35mph max. Terrain is mostly slow rolling hills, some flats, and some pretty decent hils.

With a truck with around 38 sq. ft. frontal area, a fairly bad cd, and over 7000lbs driving efficiently gets tough. Best technique so far has been cruise at 50mph and coasting in neutral down hills along with timing lights and keeping speed up as much as possible as well as keeping idle time to a min. Any help will be appreciated.

SentraSE-R · 12-25-2009, 11:14 PM

Do you need the truck for work? You could buy a $2000 beater econocar and pay for it in less than six months on the fuel savings alone.

If you have to keep the truck, you're doing the right things with it. The problem is, you can only do so much with a vehicle equipped like that.

MadisonMPG · 12-25-2009, 11:55 PM

You'll get lots of help on this site, I hope we can help.

MetroMPG · 12-26-2009, 12:37 PM

What's the truck's EPA estimate? Seems like you're doing decently already.

You'll likely find your best cruising fuel economy will happen at the lowest speed you can drive in top gear. The fact that your highway portions have low speed limits (45-55 mph) means you should be able to do that.

Does the truck have a resettable fuel consumption gauge? (I've seen these with a factory gauge, but I'm not sure whether you can control it.)

Arragonis · 12-26-2009, 07:37 PM

The most efficient mod you can make to this truck is to park it.

MetroMPG · 12-26-2009, 08:52 PM

Let's please keep this civil.

I really don't care what kind of vehicle someone drives - if they genuinely want to talk about ways to improve economy, that's good in my opinion.

MadisonMPG · 12-26-2009, 10:28 PM

Quote:

Originally Posted by MetroMPG

Let's please keep this civil.

I really don't care what kind of vehicle someone drives - if they genuinely want to talk about ways to improve economy, that's good in my opinion.

To a point, I agree with you, but once you get down in the teens you really need to get rid of it or get a good MPG car.

nubbzcummins · 12-26-2009, 10:55 PM

The other day I drove 1000rpm in o/d at 41mph as much as possible on my daily 140 mile trip to/from work and it went around 100miles per 1/8th tank mark on the fuel gauge where it normally gets 70-80 miles so it will deffinatly do better. Will drive like this the entire next tank to see what mileage I get. Would have to be a 1000+ mile tank. Tank will hold 38.4 gallons. Best tank to date was around 885 miles.