>50 mpg w/ 3/4-ton pickup
 

I achieved a milestone today: >50 mpg in my 3/4-ton diesel truck over my 24 mile commute. I got an average of 50.2 mpg on the overhead this morning. Note: I know the overhead reads 10-15% better than reality, but I guess it's a pschological thing to break the 50 mark.

A year ago I never thought this would have been possible. A year ago I was excited when I got over 30 mpg for the first time. The biggest thing that's helped me is the daily fuel log that I've kept for the last year. That's improved my driving techniques (timing lights, P&G, DWB, even some EOC P&G) as well as route planning. I've also done a grille block, a bed cover, a block heater, an oil pan heater, an an engine blanket. The biggest change recently which put me over the top was switching to some 5W-30 synthetic oil, which has bought me another ~5-10%. In addition to that it's been nice to have the temperatures come up, which have helped a lot (about 1% for every 2 deg F).

One thing that helped on this specific run was that I'd gotten home late last night (after 9) and plugged it in right when I got home. Overnight low was only about 65 F, so with my engine blankets on my engine was nice and warm this morning. Here are the rest of the details:

Distance: 23.8 miles (SSE direction)
Temperature: 66 deg F
Wind: Out of the south at 2 mph with gusts up to 7 mph
Barometer: 29.9 in Hg
Relative Humidity: 96%
Conditions: Overcast

Dave,

Those MPG's are very impressive!

One thing that should be pointed out is that your actual barometric pressure is not really 29.9.

I see that your location is in Indiana, and thus you are not close to Death Valley, or either of our oceans.

Because of this, your elevation must be higher than sea level, and your actual baro is probably closer to let's say 28.9 or so, if your elevation is close to 1000 feet.

What they report on TV is the "corrected" baro based on subtracting out the effect of elevation on the "actual" baro.

So your actual air density during your MPG run is less than what the TV broadcasts.

It's usually found by taking the broadcast baro and subtracting one inch Hg for every 1000 feet elevation.

Someone located in Denver would actually be at:

29.9 - 5.0 = 24.9 inHg baro

Jim.

Yes, when I calculate air density I correct for elevation. The weather station that I use is supposed to be at 880 ft, so by my calculation I got a density of 1.16 kg/m3.

VERY impressive! Heck, anything over 20mpg is impressive for a 3/4 ton!! And this is (in part) due to the change in oil?

That's what put me over the edge. Best I ever did before the oil change was 45.5 mpg.

Congrats, Dave!

Even if it's not exactly accurate, I COMPLETELY understand the psychological motivation/reward from getting significant round numbers on the vehicle display! ( http://ecomodder.com/forum/showthrea...nda-21484.html )

Holy cow that's impressive! Makes me wonder what's possible with my '00 Excursion 7.3 PSD?

Congratulations sir, that's is an impressive number.

50mpgUS ...in that truck is...well left me...without speech.

After seeing this accomplishment with one of the heaviest pickups, with the biggest engines you can buy, who needs a sub 2L car, or even a Prius for that matter? It beats most of the VW TDI's and other tiny cars on this forum handily. It makes my 1.8L's consumption look laughable. This accomplishment defies any record I have ever seen or imagined.

if you can get 50 MPG in a truck how can I take my boat tailed car from 50 to 75 mpg?

Before we get too carried away, I should say that I expect my actual average mileage for this tank (which is almost over) to come in somewhere between 34 and 35 mpg. But that's an average over 1,100+ miles. Nobody goes that long without having some bad days.

50+ mpg in a pickup, NICE WORK!!

That's amazing, Congradulations on that but for those who say "who needs a 4 cyl car when this pickup can do 50mpg", let's not forget how much work Dave has to do to get that 50mpg. If he drove a Cavalier or a Neon the same way he'd probably get 80mpg

IIRC, 34 MPG would still be well over 100% over the EPA rating for your truck. Congratulations!

I'm only asking because I've seen it before as a tech, but. You are using oil for a "compression ignition" engine, correct? I just don't want to see you ruin your very expensive engine.

It's Amsoil Series 3000 Synthetic 5W30 Heavy Duty Diesel oil. If you look at the tech specs here you'll find it's pretty impressive stuff:
AMSOIL - Series 3000 Synthetic 5W-30 Heavy-Duty Diesel Oil (HDD)

It's specifically designed for diesels. I don't know of anyone specifically that's run this stuff in a 6.7L Cummins like mine, however, I had heard great reviews from guys who had used it for years in the 5.9L Cummins. The 5.9L was bore and stroked in 2007 to create the 6.7L engine, and I believe the lube system stayed basically the same, so I didn't see any reason why I couldn't use it in my 6.7L.

Damn you Dave!
Up until now, I actually thought I was doing good getting 28mpg average in my 3/4 ton!!

I take some small solace in that, not having any kind of instant feedback, I could potentially be getting 50mpg single trip averages now and then and just not know it, but if you end up with 35mpg tank average its still 3-4 better than the best I've ever gotten.

Alright, I take it back, I'm not upset. This is what one calls "motivation"

Thanks Jacob, but to be fair, your truck is 24 years older than mine. At least a few of those mpg's I'm ahead of you have to be attributable to common rail fuel injection, variable geometry turbocharging, etc. That being said, I envy that weather you have out in CA. Sometimes I think of you on those days when I leave my house and it's 15 F outside...:)

And overdrive. That's what I really want.

None-the-less, it is still inspiration and motivation, which I appreciate

I would like some more info on this, I have a 95 12v 4x4 CC LB 5.9 cummins and i can get around 24 mpg at 65 mph on the freeway. I Am also a AMSOIL dealer so i'm well aware of the oil used and how awesome it works.

Next try water injection.
I am up at least 5% towing and loaded.

What oil have you been running in that '95?

I'll have to remember the 5w-30 next oil change. She's about due for one. Very nice >50!

I expect my actual average mileage for this tank (which is almost over) to come in somewhere between 34 and 35 mpg. But that's an average over 1,100+ miles.

Where the rubber meets the road . . . really impressive.

I actually thought I was doing good getting 28mpg average in my 3/4 ton!!


We'd not only have to find a way to factor different engines/trucks, but account for climate, terrain and truck use.

I'd be willing to be that the IDI Ford would "take" the 6.7L CTD if it were tasked with JA's specifics . . until a couple of weeks went by (given DD's persistence).

For what it is worth, JA "works" his truck. DD isn't. But the fuel economy lessons of both are revealing for the percentage change to the baseline.

.

inspiration and motivation productive and successful.
more on that soon, just wanted to thank you for getting it started...

I see from you're fuel log that you've added a belly pan and put up some impressive numbers on your last few test runs. I welcome the "competition". Keep up the good work!

BTW, this current tank of mine is looking like it will be my best tank ever by far. On my last tank I averaged 38.5 mpg on the overhead (34.2 mpg at the pump). 900 miles into this tank, I have an overhead average over 43 mpg and my fuel gauge is just a little over the 3/8th mark. :D

WoW! Very good numbers. Both of you are "in my sights" now. ;) I've seen a best-ever of 25mpg in my truck in Northern Utah, on I-80. That was only with a bed cover, a 1/4 grill block and a partial belly panel for mods. The air was a lot thinner up there though...
I agree Diesel_Dave, learning to adjust your driving habits is a good step in getting better mpg... I've run synthetic in my truck since the 1,500 mile mark, so I couldn't tell you what the gain was. Are you running an electric radiator fan? By the way, I modeled my front wheel arch fairings after those on your truck--thanks!

I don't have an electric fan on mine. My factory fan is a clutched mechanical fan. Even with the grille completely blocked off, my fan almost never switches on.

My old clutch fan may have been locked up, or maybe it wasn't a clutch fan at all, but it spun at all times. I replaced it with an electric, which came with an adjustable thermostat. Was pretty easy to install. The only load on my engine other than the wheels is the water pump.

UPDATE:

I filled up this morning and my real mileage for the whole tank came in at 41.0 mpg over 1,435 miles. See the details here:
http://ecomodder.com/forum/showthrea...0-a-22273.html

But you haven't yet reached 50 MPG. :p

Huge round of congratulations deserved here. 41 MPG out of a 3/4 ton truck? That's awesome!

I had to leave something to shoot for ;)

I have considered blocking the entire chrome area of my grill, and opening up the small black plastic slot in the bumper (typically where a winch would live) and using that with a clutch fan or E-fan. I'm sure it'd work on the highway. Then I could put some sort of aero nose on the front!:thumbup:

==>This weekend I installed a used Taurus 3.8L e-fan. Much better than the Zirgo and knock-off (pair of) fans I was using. It's one that several in the Dodge RAM community pick for their e-fan mod... It's a two speed, but I've not wired in the high-side yet.

Unreal, DD . . congratulations!!

Memorial Day to Labor Day ought to be a real record!

.

Damn, that's incredible.

pretty impressive improvement from the oil, wondering if you ever updated the differentials to synthetics, made the biggest or at least equal to the engine oil change in seat of the pants test so far for me last time I used it, unfortunately switched when i changed out a seal on my 300 k Ranger about four years ago, now running the valvoline semi stuff, redline worked great for me, the axle bearing surface was like polished chrome. will be going back to it this week or next time i get a dry day to change it. and will post test when done, I have an old American Flyer train set and it would barely chug around the tree, I took a match heads worth of the redline red chassis grease and put it on the tiny worm gear motor drive and the train now goes so fast it fly's off the track on curves, so I'm hooked on their stuff, even when new it never went like that,

I put some Amsoil Severe Gear Synthetic Extreme Pressure Gear Lube 75W-90 in the differential and some Castrol Transmax ATF+4 Full Synthetic in the tranny. Can't say as I saw any sudden, noticable improvement, but I'm not positive what fluid was in the differential before I changed it.

That being said, my mileage has fallen off much less this winter than last. I suspect the synthetic fluids helped with that.

Good on that, my little 2.3 Ranger has almost 400 K now of which i've driven most, one advantage i have with this testing stuff is i've only got 88 HP so any difference is noticable right away , Great work on your truck, lots of good ideas,

After re-reading this entire thread, I was going to ask what your typical driving speeds were, but as I went through I see you aren't necessarily trying to hit/maintain the speed limit. That was a foreign concept to me until now. Do you aim for a certain speed for 6th gear? I ask because I can get just over 20mpg in 4th, but I can lately hit over 30mpg in 5th at 40-45mph...

A daily fuel log? Interesting concept. Makes me wonder if I can push my commute past 30mpg. May require me rearranging my daily drive to avoid morning rush hour.

I also did some Google searching and learned I can leave my block heater plugged in for extended periods. Thought I'd risk cooking something, so I've almost never had it plugged in more than 20 minutes... Gotta thank MetroMPG for posting stats on temp rise: Experiment: how long should a block heater be plugged in? - MetroMPG.com

DD, ever look at a filtermag? I don't think it does anything for FE, but it does trap ferrous debris in the oil filter... www.filtermag.com

Wow. Ive heard for years that there was a guy who drove a chevy avalanche hybrid that claims 50 mpg on i95 he purchased used from Richmond Ford. I guess that isnt as far fetched afterall? :thumbup: