I thought this would be an interesting thread to start, to see the most efficient way to drive. Has anyone compared their mileage driving like grandma with very little acceleration to driving with more accelearation. So the scenarios are...

1. Use little acceleration to get up to speed, so you spend more time accelerating, therefore burning fuel for a longer period of time.

2. Use heavier acceleration, so you get up to speed quicker, but burn more for a short time.

Just a thought that would be interesting to know... I can't keep my foot out of it anyway, so I'm a bad tester

 

Try using the tach for you test. Keep it under 2k for city. I try to do that as much as I can. It works pretty good. On the Highway at 75mph, Im just over 2k.

 

I don't think I could ever drive "like a grandma" enough to calculate my mpg, it would drive me crazy! However, the one thing I did try, that was very difficult, was to drive no faster than 65mph on a 320 trip (all freeway in a 70mph zone) and then do the same trip going 72mph (both times with cruise on). Going 65mph I got 19.5mpg and when I did 72mph, I got 18.7mpg. I have only tried this once however I believe the results. Wind drag makes a difference!

I think will will continue putting my foot in it to make sure my turbo stays clean!

 

When in top gear the magic number is 2,000 rpm's.

I find that if I cruice at 70mph (tach is at 1,900 - 2,000) then I get 18 - 19mpg highway in the summer.

If I cruise at 75 - 80mph and the tach is at 2,200 - 2,600 rpm's, I get 16mpg highway.

I have just learned to lock it in at 73mph with the cruise as this (with a 3.73 rear-end) gets me my best mileage and just fast enough that I can cruise in the right lane or even pass a few people.

With a 3.73 rear-end... 2,000rpm's is the max for bet mileage... and of course... if one drove 55 - 60mph then they would get better mileage... but who's going to drive that slow.

 

2000 should be the magic number as stated. This is where our trucks produce the peak torque. So with that said that would be where the least amount of load is on the engine, giving you better fuel mileage.

 

I have tried keeping under 2000rpm in town but is insanely slow to get to speed, and besides that it is just too hard to not put my foot in it. I Filled up today and averaged 10mpg empty and am hoping that the 35's have something to do with that. I've got some stock michelins on the way hopefully they will help remedy this.

 

Unfortunately having the 4.10 gears, I can't do 70 and keep it at or under 2000 rpms, I have to do between 60-65 in order to stay at that magical number. I have found out that I can do that when I'm pulling the horses or anything extremely heavy, but I just can't do that when I'm empty or pulling some trees. I'm not getting any younger, besides that, someone has to let the car driving people know that diesels have more horsepower then their dinky four cyclinders(and even some drivers of stock v8 cars have had wide eyes as I have gone by)

 

I have 35's on my truck and have never got that bad of mileage. Might want to look into that a little further.