MPG with LB7

[DickWells]

Just figured out my last tankfull. Got 15.2 for 360 something miles, topped out right up to the meniscuss by rocking the truck--both fillups. That's solo driving, BTW. All in the Brownsville area. A lot of stop and go, city driving, with 3 trips to Harlingen and back thrown in. Am I happy? Don't know, should I be?
Here,s something to ponder. This was just LS diesel, bought at the same Murphy/WM pump, both times. I think this is better mileage than I got solo at home this last summer on ULSD. This isn't the first time that I've suspected poorer mileage with UL. Seems like I've read that opinion in here before.:( Maybe it's just part of the price we have to pay for going green?
Any thoughts/comments?
Dick Wells:)

[JohnC]

This was just LS diesel, bought at the same Murphy/WM pump, both times.


Are you sure? Around here the only way to get anything other than ULSD is to buy home heating oil...

[SuperPRO56]

Ive been doing back to back fuel runs on the different settings of the Edge. So far, I got 18.9 MPG on setting 1 (economy) and 17.5 on setting 3 (drive). All were done on ULSD treated with power service fuel treatment. I was pretty easy on it the whole run and got just over 400 miles on my 18.9 MPG run. Next one I do will be on setting 5 (extreme), but I will drive that one easy so I get a comparable run.

Last time I got 15 MPG was on race setting and drove with a heavy foot.

[Mark Rinker]

Questions:

Oil you run (brand and viscosity), frequency of oil changes
Air filter you run, frequency of filter changes
Tire size, pressure
Fuel additives and frequencyStop and go kills mileage. I suspect you'd bounce up to high teens if on a 300-400 mile, 65mph cruise with treated fuel, clean air filter, full pressure stock tire size.

[DickWells]

John C.: Yup, I'm sure. Like you, all I can get back home is ULSD, but here in Brownsville, all they have at Wal Mart is LS, 500 ppm. Got a guy here in the park who has an 08 DM. He can't fill up at WM, here.

Mark: My oil is Rotella 5-40 synthetic, running through an Amsoil dual bypass system. Around 6K on it right now, with honey color showing. Had to add a quart back about a thousand or so.
Air filter is S&B. Will need servicing soon.
Diesel services additive, every fill-up. Usually use the gray can.
Tires are GY Tracker IIs - 265 - 75s at 80 psi, cold, F and R. NOT great tires. They're not round! Can't wait for them to wear out, but it'll be a while.
Stop and go does kill the mpg. Also, I was running the Edge on level 3 and 4 through much of this tank. Took it pretty easy on the right pedal most of the time, but got into it a few times to scoot around some slow pokes.
I got over 19 a year ago, going home for Christmas. I had the Hypertek installed then, on level 3. I've swapped Edge units since then. In 07, going to Alaska, I kept the old Edge unit on level 2 (towing), and got 13.2, towing, with an all-up weight of 19500 for 8000+ miles. We left all the guns and the big Traxter ATV in OR for that trip. Dropped about 1500 lbs. Near as I could tell, I got the best mileage and had the best power on the caravan. We had six DMs, one 06 Cummins stick shift and two 7.3s in the mix. The rest were motor homes and a couple of SUVs pulling smaller trailers. At 10000 + lbs, my trailer was about the lightest. Most of the others were 5th wheelers. Biggest surprise for me was the 06 Cummins. I'd just blow by him on any grade with just a little push on the throttle. Amazing how the DM pulls in 4th lock-up with very little extra throttle opening. The Cummins heated up a lot on those pulls, and the driver told me that he was doing all that he could do in 3rd gear. I would have thought the Cummins would out pull a DM, but I was wrong. His trailer out-weighed mine by over 1000 lbs, though.
My old Edge unit served me well until we got back south. Did some funcky things that made me remove and replace it. Edge swapped it for free! So far, so good on the new one.
I'll be doing some cruising around south Texas after we get back from Christmas at home. We're flying. I'll keep it on level one, and get a better shot at solo mileage. One thing I can do now, is to get into my log and calculate everything from back when I got back from Alaska. It's all there, just never bothered to add it up.
DW:)

[Mark Rinker]

Sounds like you are well on top of all the variables, Dick.

My only advice to you would be change brands of oil. I used to use/burn lots of Shell Rotella, and once I made the switch my oil consuption has stopped. My recommendation would be Mobil Delvac synthetic (silver jug).

With your extra filtration, what are your oil change intervals? Do you have oil analysis done periodically to make sure you are in good shape? We do 8-10K intervals with Delvac standard and 10-12K with Delvak synthetic. Intervals are shortened during hot summertime towing, or any extreme conditions or loads.

Interestingly, these long oil change intervals almost always match the 'CHANGE OIL' request calculated by the ECM. Our driving patterns have so few start and stop cycles that the computer isn't calling for short change intervals, either.

[DickWells]

Thanks Mark: Haven't had the system in long enough, yet. Will get the oil checked before I start to tow again in Feb, or Mar.
Rotella has never been my favorite, either. Back when I was towing with my 6.5 Sub, I happened onto some Castrol Syntek blend 15-40. I almost doubled my miles before adding a quart. Wal Mart stopped carrying it, so I went back to whatever I could get. I'll try the Delvac when I change next time. Thanks for the advise.
Dick:)
PS: Is the Amsoil or Royal Purple worth the added cost, you think?

[JohnC]

here in Brownsville, all they have at Wal Mart is LS, 500 ppm.

Thought that was verboten! Even our off road fuel is ULSD.

[DickWells]

I was telling my wife today about your post, and the LS here in TX. I think I've seen it elswhere in the South, but not sure. She said, "Well, it is Texas, after all." Guess she's right. Texas is different. Sort of like being from the Independent Republic of Vermont!
Gotta drive by the other WM on the other side of town. They're about a dime higher there. Maybe they do have ULSD. BTW, I paid $2.389 with my Wally World card. Still too high, but less than half what I was paying a few months back.
DW:)

[Runaway_Dmax]

Sounds like you are well on top of all the variables, Dick.

My only advice to you would be change brands of oil. I used to use/burn lots of Shell Rotella, and once I made the switch my oil consuption has stopped. My recommendation would be Mobil Delvac synthetic (silver jug). .

x2, seems like everytime I tried to use any Shell oils my consumption went up.