MPG is better with...

[Goofyexponent]

It's too early to say for sure, but I think I picked up 2 MPG or so when I did my ZF swap. Once I run a few more solid tanks through it and calculate mileage...I will know for sure.

Anyone who did an auto to manual or vice versa swap will be the PERFECT candidate for this. The only thing that changed was the Auto for a Manual in my truck.

With my winter tires, realistically, I was getting 17 - 18 MPG with my E4OD...but I am getting closer to 19 - 20 MPG now with my ZF....3.55's in the rear.

 

[Agnem]

I'm cringing Scott!



And I thought my 7.3 was bad.

 

[The Warden]

This may not help that much, but my old E-350 van (6.9l n/a, C6, 3.54 rear end) typically got 13 to 14 mpg...compared to my truck when I first got it (6.9l n/a at the time, T-19, 4.10's) which got 14 to 15 mpg.

With the ZF swap, I'm now averaging 17 mpg out of my truck, and if I'm gentle on the throttle and set the cruise at 55, I can get 19 to 20. I can't wait to see what my mileage does after I get the Doug Nash unit installed

 

[snicklas]

I understand Mel.... if I kept it under 2500 like most of the IDI's run.... I would make the truck mad. The one thing with a 6.0, believe it or not, it loves to be worked. I do not abuse my truck, but I do not drive it like a grandpa. I have run mine like this since I got it, and I have not had EGR or Turbo problems. Keep a 6.0 stock, and run it somewhat hard once in a while, it is very happy. Put around in it, and it get really mad.

If I drive it to work for a few days, after Momma had been running it in town, at low speeds, getting the kids from school....etc and I drive it, there is a definite power difference. When I get on the interstate the first time, I will do a hard, WOT accel onto the interstate. I can see haze from the exhaust. After a couple of those, it runs much better, and has more power.

 

[Diesel JD]

I did a C6 to T18 swap, nothing else changed. My mileage is all over the place before and after. Seems to be that using B100 in a suburban environment with some highway I get 13-13.5, all highway I get 15.5-16 with the T18. In all honesty I got similar numbers with the C6. There seems to be more power available with the manual though. It'll be interesting to see what I get when the brownie is finally installed. Honestly I love rowing gears though, so I'm biased against the autos, I'm always sad when I get to 4th that I don't have a few more.

 

[JLDickmon]

keeping your foot out of the go pedal makes the most improvement..
so does proper tire inflation

 

[seawalkersee]

There's about a 600 rpm difference at cruising speed, so Mel's theory is obviously at work here.

Not a theory...its facts. Im not sure why but I was getting 18ish with mine prior to the rebuild. Now that I am in the rebuids, I have to run it for a while to get it right. I already know the power is going to be better, but I am really interested in the efficiency of the thing. I will run it NA until I get the mounts built for the blower. Who knows how long the test will take after the install since it MAY be a restriction at idle, but if it runs right, I should have good numbers with a blower within a year...With that being said, I have some property for sale. Something about a golden bridge comes to mind. 2-3 years it is.

SWS

 

[RLDSL]

And it's even more better ( such grammar ) with two manual trannys in there

 

[Goofyexponent]

Ok!

Time for some actual distances and volumes.

We took out annual trip to Pugwash (way up north from here) and I was REALLY surprised.

Two years ago, I drove the trip and burnt a little over 1/2 a tank.

365 kilometers on 46 liters works out to 7.93 kilometers per liter (365/46=7.93)

This works out in miles per gallon..

365 kilometers to miles (365/1.61=226 miles)

46 liters to US gallons (46/3.78=12.16 gallons)

so....this works out to 18.58 miles per gallon (226/12.16=18.58)

That was with 265/75R16's (mild tread), Dana 50TTB, 2" F250 rear blocks and a healthy E4OD.

THIS year...we made the trip again. This time the truck had a D60, 235/85R16's (AGRESSIVE TREAD), Dana 60 fromt, 4" lift blocks in the rear, 1200 pounds of gravel in the bed and a ZF 5 speed.

We drove to Pugwash with the truck, and back home, then I took the truck to work in a blinding snowstorm at 1 am and then back home the next day.

I put 380 kilometers on the same amount of fuel as our one trip to pugwash.

Seeing as I was in 4th gear in the snowstorm on the way to town, i see that as bad for mileage.

I averaged 8.44 kilometers per liter (380/45=8.44)

In miles per gallon this works out to be..

380 kilometers is 236 miles (380/1.61=236 )

Again, 45 liters is 11.9 gallons (45/3.78=11.9)

So, I got 19.83 miles per gallon (236/11.9=19.83)

You might think that there is a difference because I drove to work. You are wrong.

We moved to Nine Mile River, which is between Pugwash and Halifax. Where I work is litterally 2 miles from where we used to live. We drove through a snow storm last year too, same as I did on my way to work when we got back. It's the same trip, same roads, same distances, the only thing changed was the 5 speed....and the fact I had WAY more weight in the bed. The extra 15 kilometers is accounted for too. I have a bit of a hike to the fuel station, just over 14 kilometers one way. I fueled up before we left home to head to Pugwash, that is the extra 15 kilometers.

This is hard fact. Actual numbers I gathered I went from 22.3 mpg Canadian last year to 23.7 this year.

The ZF seemed to really come though on this one. I gained MPG despite adding weight and agressive tires.

 

[oldmisterbill]

I've ben wondering about 3:55 behind my non wastgated E40D with -locked convetor-maybe turn the fuel back down a bit since I don't plan on towing heavy again. I could just keep my foot out but sometimes it gets to be too much fun just to lay it wide open.
I also wonder how low the E40Ds low is compared to a C6. I am considering towing some with a light single axle trailer. However it wouldn't be daily - just on occasion. My ole 84 with 3:55 & a C6 did light towing (under 10,000) locally just fine. Except I think I used low range a couple times in the New England hills when I had to start up hill.

 

[david85]

The E4OD feels very much like a C6 up to 3rd gear. 1st gear is barely noticable as having a bit more torque and 2nd should on paper have some extra too but I couldn't tell. Reverse is weak though and you will want to use low range if you have a lot of weight to push backwards. Even forward could use the extra help if you have the transfer case.