Enclosed Trailers....

[PxTx]

This is a real helpful post. Seems like my gas engine has cost me $2,652 more in fuel to drive the 156k that I have on it now. Maybe I have more confidence and certainly more experience in my oil changes. I've only changed the oil every 10k in my truck, but it uses a quart (since new) about every 4-5k. Seems like my buddy with the 06 D is 2x as many oil changes as I am doing. I'm sure I would like a Duramax if I owned one.

Just to clarify, what kind of milage would you expect out of a Duramax pulling an enclosed trailer?

Are there any confirmed aero mods with measurable gains on mpg? Even if there were, for the few times a year I pull my trailer, I don't know if there would be a positive ROI.


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chevy454</div><div class="ubbcode-body">We've had a couple 8.1L rigs and 3 generations of Duramax trucks, and here are the general numbers I use when people ask about cost differences...

I've driven the same route to/from work (55mph speed limit, open highway) for 3+ years now, with 3 different 4x4 trucks...and I've kept nearly every fuel receipt I've ever gotten in this time. The 8.1L was a ccsb, and generally got 11-12mpg as a daily driver, and would *occasionally* slip in a 13mpg if I ran over to West Plains (25 miles of 65mph 4-lane)...and this was with an ecm tuned for mileage (Wait4Me). My LB7 Duramax was a cc/drw, and it would see 16-18mpg, but was a chronic injector eater as are all LB7s (unfortunately). My current truck is an LLY ccsb, and sees 15-17mpg, but will slip in an 18mpg if I see the 4-lane...dad's '06 gets nearly identical to my truck. Having said that, here are some numbers I use when people ask about cost to drive...

8.1L = $3.25/gallon, 12mpg = 83.3 gallons per 1,000 miles = $270.72 (regular)
8.1L = $3.55/gallon, 12mpg = 83.3 gallons per 1,000 miles = $295.71 (premium)
LLY = $3.75/gallon, 17mpg = 58.8 gallons per 1,000 miles = $220.50

The higher the fuel prices are, the more savings you'll see from the Dmax...plus, you can easily add a tuner that will gain mileage/power at the push of a button on the Dmax, versus the gas truck which will only see marginal gains. But, aside from the higher initial buy in price (you can really tighten it up if you buy used), you have the additional cost of 2 more quarts of oil at service time plus the price of a fuel filter every 15k miles with the Dmax. I loved my 8.1L, but my Dmax just does pretty much everything better... </div></div>

[ORIGLS6]

My son has an '02 D'max/allison 4WD Crew cab Dually. He has the tune-on-the-fly programmer, 5&quot; exhaust and an upgraded air box. He runs right at or over 20 mpg on the highway. I hooked my 20' enclosed trailer to it and it pulled the mileage down to 19! [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img] He pulled a 40' open gooseneck with two mud trucks (full size 1/2 ton p/u), and still got 15 mpg on the open road.
The DuraMax engine is one of GMs best products, and like Rob said above, you can get pretty good pricing on them if you're looking to buy used.

[RAIIIT/A]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ORIGLS6</div><div class="ubbcode-body">My son has an '02 D'max/allison 4WD Crew cab Dually. He has the tune-on-the-fly programmer, 5&quot; exhaust and an upgraded air box. He runs right at or over 20 mpg on the highway. I hooked my 20' enclosed trailer to it and it pulled the mileage down to 19! [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img] He pulled a 40' open gooseneck with two mud trucks (full size 1/2 ton p/u), and still got 15 mpg on the open road.
The DuraMax engine is one of GMs best products, and like Rob said above, you can get pretty good pricing on them if you're looking to buy used. </div></div>

The Duramax engine is technically an Isuzu product..

[Chevy454]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pxtx</div><div class="ubbcode-body">This is a real helpful post. <span style="font-weight: bold">Seems like my gas engine has cost me $2,652 more in fuel to drive the 156k that I have on it now. </span> Maybe I have more confidence and certainly more experience in my oil changes. I've only changed the oil every 10k in my truck, but it uses a quart (since new) about every 4-5k. Seems like my buddy with the 06 D is 2x as many oil changes as I am doing. I'm sure I would like a Duramax if I owned one.

Just to clarify, what kind of milage would you expect out of a Duramax pulling an enclosed trailer?

Are there any confirmed aero mods with measurable gains on mpg? Even if there were, for the few times a year I pull my trailer, I don't know if there would be a positive ROI.</div></div>
Oil changes are up to the owner's discretion, but my manual says every 3,000 miles for gas engines and every 10,000 miles for the Duramax. There seems to be the same mpg gap between the gas &amp; Dmax when loaded vs. empty (~5mpg) assuming the driving habits are the same...the problem I've noticed with our trucks, at least, is that our Dmax powered trucks pull the trailers so effortlessly that we tend to speed more often, which really seems to hurt the mileage because the turbo is moving so much more air.

And like Cumby stated, the newer diesels respond so well to such simple mods as an airbox and/or exhaust...many guys are getting their trucks tuned with EFI-live and seeing low-mid 20s empty. I tried and tried with my 8.1L, and while I loved that truck and it was a *great* truck, it never responded mileage-wise...taking the torque management off was worth the tune, though.

Aero mods...I've heard a camper shell helps, as does a wing to get the air over the nose of the trailer, or even switching to an &quot;aero&quot; trailer...but I've never tried any of the above.

I'm not sure I understand the part in bold...