Jump to content
Mopar1973Man.Com LLC
  • Welcome To Mopar1973Man.Com LLC

    We are a privately owned support forum for the Dodge Ram Cummins Diesels. All information is free to read for everyone. To interact or ask questions you must have a subscription plan to enable all other features beyond reading. Please go over to the Subscription Page and pick out a plan that fits you best. At any time you wish to cancel the subscription please go back over to the Subscription Page and hit the Cancel button and your subscription will be stopped. All subscriptions are auto-renewing. 

Fuel Efficiency of the 04.5-07....


Recommended Posts

Judged a retriever hunt test this past weekend NW of Madison, WI.  They were paying mileage, and I needed fuel before the trip anyway, so I filled up with 29.995 gallons and had 628 miles on the tank of fuel for a tank average of just over 21mpg!!! 

 

To and from the hunt test was about 130 miles each way with about 75 miles of driving to the hotel and test sites over the weekend. Had just over 400 miles on this tank of fuel before the gauge dropped below 1/2 tank!! Was a very hot, humid weekend here also.  My truck has always gotten stellar mileage in the hot weather.

Link to comment
Share on other sites

Still on the same tank of fuel from my above post.  Just thought I'd add this picture for y'all.  Took it whist driving today to go dog train.  Shows the level left in my fuel tank and how many miles I have (at the time) on the tank!!  Enjoy................I sure am!! :cool:  :cheerleader:  :thumbup2: post-7-0-91086300-1401996465_thumb.jpg

  • Like 1
Link to comment
Share on other sites

  • Staff

Warmer air is two fold, but mainly the resistance is lower and the fluids are always warm. 

 

It goes back to winter temps kill winter mileage, not winter fuel. Many people refuse to believe it, but it's true.

 

It simply takes less hp to drive at speed in summer than winter, the a/c does hurt but not as much as the warm air gains.

 

My car mileage usually peaks in April, warm enough to be very efficient and minimal warm-up and not using the a/c often. Once it get really hot I lose about 1 mpg over April, but still 1-2 better than winter.

 

I might look into the files and see if I can find out much timing is even changed by IAT on a CR.

  • Like 1
Link to comment
Share on other sites

Warmer air is two fold, but mainly the resistance is lower and the fluids are always warm. 

 

It goes back to winter temps kill winter mileage, not winter fuel. Many people refuse to believe it, but it's true.

 

It simply takes less hp to drive at speed in summer than winter, the a/c does hurt but not as much as the warm air gains.

 

My car mileage usually peaks in April, warm enough to be very efficient and minimal warm-up and not using the a/c often. Once it get really hot I lose about 1 mpg over April, but still 1-2 better than winter.

 

I might look into the files and see if I can find out much timing is even changed by IAT on a CR.

 

The one trip of mine back from NoDak that I've referenced a few times here was in temps of about 20*F.  Twas roughly the same temp at home as when we left.  We did have a 10-15mph NW wind blowing us home;  but I was running the truck 75-80mph, and still got right at 21mpg.  Just the truck loaded to the gills with 3 guys, 2 dogs, and hunting gear for 4 days.  Just saying.

Link to comment
Share on other sites

  • Staff

My best tank was also in cold weather, sub freezing for most of it. The kicker was the 1000' drop over 300 miles and the 10-15mph tail wind.

 

I didn't say you can't get good mileage in cold, you just get better in warm air under identical conditions otherwise.

Link to comment
Share on other sites

Filled up today just as the DTE on the Lie-O-Meter hit 0.  Wound up with 720 miles on the tank and filled up with 32.4 gallons for an average of 22.2mpg.  Probably about 80-90 miles of the tank were towing my work trailer.

  • Like 2
Link to comment
Share on other sites

  • 2 weeks later...
  • Staff

My current tank, only 1/3 burnt, is looking very good. I was about 220 miles at 3/4, normally I am ±110 towing and ±180 empty. I ended up towing the TT 18 miles, and now am hooked up to the TT with a full load, around 19K GCW, so the mileage will drop quick on my way to fuel up... but I would say I was all of 20-21 for the first 200 miles of the tank, very good for me.

Link to comment
Share on other sites

546.xx as the needle centers the 1/4tank mark.  Could be another 700+mile tank............but I've gotta work tomorrow and the  next day towing the trailer.  Overhead Lie-O-Meter is reading 27.8mpg and  246DTE.

 

 

This tank wound up at  21.3mpg.  Not complaining one bit.

 

The tank I'm on now will be a typical summer tank and be in the 19-20 range.  Much more towing.

 

Have a Kentucky trip scheduled for Sunday-Wednesday.  I'll post mileage results.  Plan on going down with the 3 dogs and some carpentry tools to help a bud frame out an "out-building" on his property.  I'll keep the speeds at my normal 65-68mph on the Interstate to and fro.

Link to comment
Share on other sites

This tank wound up at  21.3mpg.  Not complaining one bit.

 

The tank I'm on now will be a typical summer tank and be in the 19-20 range.  Much more towing.

 

Have a Kentucky trip scheduled for Sunday-Wednesday.  I'll post mileage results.  Plan on going down with the 3 dogs and some carpentry tools to help a bud frame out an "out-building" on his property.  I'll keep the speeds at my normal 65-68mph on the Interstate to and fro.

 

Kentucky trip report...................

 

Left my house with 2.5 miles on the tank of fuel as I fueled up about 6 hours earlier.  Drove down to Berea, KY;  spent 2.5 days there and drove back to the NW side of Indianapolis, IN all on 1 tank of fuel.  That's 724 miles, and I stuffed 32.7 gallons in;  for an average of 22.1 mpg.  Was running 65mph with 10mph crosswind to and fro.

Twas another 215 miles home after the fill up. 

 

Truck ran great.  Just under 210,000 miles now.

Edited by dorkweed
Link to comment
Share on other sites

It seems that even CR engines are affected by the warmer air. :think:

My 05 does way better mileage in hot weather and or in the mountains. Normally hangs in the 16 mpg range easy dd around here, last trip a few years ago to Phoenix and back 4500 miles in 10 days averaged 19.8 overall lots of hot weather and mountain driving that trip.

  • Like 1
Link to comment
Share on other sites

I truly believe now that the "free-spin" hub kit has gained me at least 1mpg.............................and that's saying after 40,000+ miles after the install!!!  I think I can say that for me being more anal than most about mileage and such. The hubs run cool even in really hot weather......................they ran warm just after the install but I think that was just the bearings "setting/breaking in" IMHO!!

 

If I hadn't done the free-spin kit;  it'd be a matter of a few more months where I'd be changing the front axle U-joints based on historical averages for my truck.  Just rotated tires and lubed the front end, and the axle U-joints look great. Pumped int the grease and got grease oozing out from all the cups on both sides.

 

I make it a point to lock the hubs about once per month and drive about 30-40 miles to make sure the U-joints and the front diff seals stay lubed.

  • Like 1
Link to comment
Share on other sites

  • 3 weeks later...

I'll chime in here with my '06. drive 75 miles one way to work running 72-85mph lie-o-meter says 28+to 27.4. Actual measured is 19-21 depending on where I fueled. If I keep the speed below 70, I gets up to 35+ on the lie-o-meter. Never had the chance to measure that, for actual milage.

Link to comment
Share on other sites

×
×
  • Create New...