I was going to use a "fuel economy" title, but it seems inappropriate.
I've been keeping a few numbers on the last couple of trips I've done and here's a weird thing, there isn't much difference when hauling the big trailer vs the small one.
I don't want to suggest that this is generally applicable, so here are two of my cases and a couple of shots at explaining it;
1) 1763 miles. 4 horse head to head gooseneck trailer of unknown weight, with 4 horses (OK, 3 and a pony), 13.5 MPG.
2) 1486 miles. 2 horse bumper pull trailer weighing under 3,000 lbs. first half with 1 horse, 2nd half (return trip) with horse and one pony, barely made 13.5 until about the 1300 mile point, finally came in at 13.7.
So this means for every $135 I'd spend in fuel using the small trailer it "SAVES" me $2 ? Less than $2 a day. BIG FAT DEAL !
Both journeys were from Mass and went down through CT and NY to PA, MD, VA area, probably 80% or so the same route, both mid week (the traffic variable), similar weather conditions and construction delays. So I'm having a bit of a hard time explaining the lack of "savings" with the smaller lighter bumper pull trailer, especially as it was carrying less than half the weight IN it and it certainly weighs a lot less than half of what the big one weighs.
Possibilities;
My earliest guess was that I was compensating, i.e. feeling less drag with the small trailer and treading on the loud pedal harder to take advantage of it and make better time. I checked the logs, nope the average is within a percent.
Next guess was following vs head winds. This is still a possibility, since I have no way to rule it out or in - BTW, since the trip to Wyoming and the head winds on I-80 I'd like an air speed indicator on the truck, just for fun and so I know WHY the fuel is going at 4 MPG when I'm barely doing 50 MPH (-:
Anyway, they were at similar times of the day so I doubt that the DIFFERENCE in effect would be THAT much.
Now the current favorite theory; Aerodynamics, or if you're old enough "Streamlining" (-:
I'm beginning to think seriously that the goosie and truck make an aerodynamically more efficient combination than the bumper pull trailer and more widely separated truck, despite the wedge nose on the BP vs the flat nose on the Gooseneck. I can't tell from bug splat patterns, sure the BP looks bad, but so did the gooseneck a couple of weeks ago - OTOH, there are probably a few more bugs around now.
So anyone else notice this effect ?, or is it just me, my trailers, my trips, my "driving", etc ?
Posted 2005-06-10 7:56 AM (#26311 - in reply to #26293) Subject: RE: (relative) fuel use.
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Posts: 222 Location: Kaufman, Texas
Reg,
Although my trips are not near as far as yours, I also have not noticed much difference in fuel usage from pulling my 9" SW LQ 3 horse slant trailer with 2 horses versus pulling my 3 horse slant 16' BP with 2 horses. Wish I could get 13.5 mpg. Only get about 11 mpg with my F250 in either case.
Posted 2005-06-10 8:01 AM (#26312 - in reply to #26293) Subject: RE: (relative) fuel use.
Elite Veteran
Posts: 788 Location: Tenn/Ala.
No Reg, I've not documented like you have, but "seat of the pants" has told me several times that a small/medium goose will pull easier than a BP (on a long bed pick up). Like you, I've also likened it to airflow being more consistent over the cab & then around the trailer, rather than pooling in the bed & then smacking the BP.
On an aside, have had the opportunity to pull identical GN stock trailers- except one was 6'6" tall and the other was 7' tall. Made almost .5 MPG difference on same route. And the same seat of pants says the new trend towards 7'6" tall adds up too.
Had a customer tell me he gets 1 more MPG with his tapered nose LQ (12000#), than he does with his square nose stock combo (7500#).....
Posted 2005-06-10 9:33 AM (#26320 - in reply to #26311) Subject: RE: (relative) fuel use.
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Originally written by Texas Butch on 2005-06-10 7:56 AM
Reg,
Although my trips are not near as far as yours, I also have not noticed much difference in fuel usage from pulling my 9" SW LQ 3 horse slant trailer with 2 horses versus pulling my 3 horse slant 16' BP with 2 horses. Wish I could get 13.5 mpg. Only get about 11 mpg with my F250 in either case.
Thanks for the feedback.
I'm not that much of a detail oriented person, all credit goes to the truck for collecting the fuel and mileage numbers and Street Atlas with the GPS unit for collecting the logs. 13.5 on long trips, more like mid 11s on suburban/rural non highway trips. The head winds of Wyoming knocked me down to 11.5 and I didn't get it back on the return leg )-:
Then there's the speed thing, as I watch the "instananeous MPG" display there is a steep rise in consumption above about 57 MPH, trying to maintain 65 on the long grades is expen$ive.
Not that this is the most expensive part of being around hossies...
Posted 2005-06-10 10:04 AM (#26322 - in reply to #26321) Subject: RE: (relative) fuel use.
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Originally written by NoSpam on 2005-06-10 9:52 AM
Just curious, what is your MPG not pulling a trailer?
Thanks,
Michelle
Who ? Me ?
I havn't measured it on comparable highway trips, mostly because if I don't take a trailer I don't take the truck. When the truck was new and I was driving it just for the pleasure of driving it I was getting around 17, it was improving as it loosened up but I doubt that it would have got above 18.
Posted 2005-06-10 11:06 AM (#26325 - in reply to #26322) Subject: RE: (relative) fuel use.
Veteran
Posts: 140 Location: Colorado
Thanks Reg, I was curious about the ratio. My Dodge diesel gets about 20 mpg on the highway unloaded, it gets about 10-12 when I have the slide in camper and 3H bumper pull w/ two horses, gear, water, etc.
It will be interesting to see how having the new (heavy!) gooseneck changes things... Maybe the horrible aerodynamics of my old setup were part of my low milage #'s. I can hope...
Posted 2005-06-10 11:18 AM (#26326 - in reply to #26293) Subject: RE: (relative) fuel use.
Member
Posts: 41 Location: n/a
I hope these are ok questions to ask. From what I am reading, this is what I am thinking. If anyone could please give me correct or incorrect on these statements. Thanks
1. Tappered nose is better on gas than flat nose.
2. Goose neck is better on gas than tag along / bumper pull
3. Shorter height (6'6") is better on gas than taller height (7'6")
4. What about width? Would a smaller width (6') be better on gas than a wider width (8')?
(I understand in comparing trailers it would depend on more than mentioned above such that as weight, etc... I am asking these questions as an in general or comparing two trailers completely alike)
Posted 2005-06-10 11:58 AM (#26329 - in reply to #26293) Subject: RE: (relative) fuel use.
Extreme Veteran
Posts: 326 Location: Palmdale, CA
Intutitively, that seems about right. When you look at the savings on a per day basis, the savings don't look that spectacular, but on a monthly, yearly basis, starts to look better.
Also, I bet at highway speeds, it doesn't take a whole lot more fuel to keep the small trailer moving, vs. the large trailer. The biggest difference would be starts from a dead stop and climbing grades. With those being minimal, I assume, the difference wouldn't be that great especially over a long trip.
Posted 2005-06-10 1:44 PM (#26343 - in reply to #26326) Subject: RE: (relative) fuel use.
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Originally written by keliy23 on 2005-06-10 11:18 AM
I hope these are ok questions to ask. From what I am reading, this is what I am thinking. If anyone could please give me correct or incorrect on these statements. Thanks
1. Tappered nose is better on gas than flat nose.
2. Goose neck is better on gas than tag along / bumper pull
3. Shorter height (6'6") is better on gas than taller height (7'6")
4. What about width? Would a smaller width (6') be better on gas than a wider width (8')?
(I understand in comparing trailers it would depend on more than mentioned above such that as weight, etc... I am asking these questions as an in general or comparing two trailers completely alike)
Thanks Kelly
I believe any and all questions are OK to ask, the answers are the hard part.
1) Tapered nose: I'm not convinced by the ad copy. I think the BIGGIE is with the partial vacuum that the flat backs of horse trailers pulls along behind them. {Brenderup might be different here ?}
2) From my very limited study I think the improved aerodynamics of the Gooseneck/truck vs the BP/Truck might be just about making up for the increased weight. I'm more than a bit surprised by this and have mixed feelings about it. I'm happy that the goosie is that good, but a bit disappointed that the BP isn't much better. I'm trying to not let this cloud my view of possible/probable causes.
3) Lower trailers push less air, but there may be an optimum height that works best (flows air best between truck and trailer). I absolutely WILL put up with the effects of having 7' 6" interior height in the trailers. If I was exclusively hauling minis or Shetty ponies it might be different (-:
4) Width is probably a factor, but A_Dynamics is sometimes harder to predict than a sw radio mast. The same truck and trailer width might be optimal. Thinking about it my big heavy gooseneck trailer is 8ft wide and the BP is only 7ft wide, so I guess the lack of savings is even more disappointing.
In light of another current topic I guess I should add that I'm a tire and hub feeler. Part of my regular stop routine involves checking all the tires and hubs for temperature. It even comes before watering the hossies, because in 15 or 20 minutes hubs and tires are likely to cool (a bit).
Posted 2005-06-10 7:33 PM (#26358 - in reply to #26293) Subject: RE: (relative) fuel use.
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Posts: 1416 Location: sc
well i agree it probably has a lot to do with aerodynamics. and here is another angle ive discussed over a beer or two.....
when talking about fuel mileage it generally refers to reasonably steady state crusing, because as we all know you dont get any fuel milage going up a hill. that being said lets look at a hypothetical diesel engine, say at 65mph in top gear it is putting 400# of torque to the ground. and a gasser making 200#. and again as we all know torque is bascially a measure of how much work is being done or in this case how much weight is being moved. now the math here is not perfect but i think youll get my drift. lets say it takes 100# of tq to move just the truck @65mph, now lets say it takes 200# to move the truck and BP and 300# to move the truck and GN. or even the other way around for the aerodynamics, at any rate the 400# has not been reached. its using enough power with either trailer to use more fuel than empty but hasnt hit the "point of diminishing returns" now using those numbers with the gassers 200# its going to have to kick down a gear to acess more HP and TQ to move the load which is why they get considerbly less mpg under a load. there are formulas for this type of stuff out there, but im not an engineer.
Posted 2005-06-10 7:56 PM (#26359 - in reply to #26358) Subject: RE: (relative) fuel use.
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Originally written by chadsalt on 2005-06-10 7:33 PM
well i agree it probably has a lot to do with aerodynamics. and here is another angle ive discussed over a beer or two.....
when talking about fuel mileage it generally refers to reasonably steady state crusing, because as we all know you dont get any fuel milage going up a hill. that being said lets look at a hypothetical diesel engine, say at 65mph in top gear it is putting 400# of torque to the ground. and a gasser making 200#. and again as we all know torque is bascially a measure of how much work is being done or in this case how much weight is being moved. now the math here is not perfect but i think youll get my drift. lets say it takes 100# of tq to move just the truck @65mph, now lets say it takes 200# to move the truck and BP and 300# to move the truck and GN. or even the other way around for the aerodynamics, at any rate the 400# has not been reached. its using enough power with either trailer to use more fuel than empty but hasnt hit the "point of diminishing returns" now using those numbers with the gassers 200# its going to have to kick down a gear to acess more HP and TQ to move the load which is why they get considerbly less mpg under a load. there are formulas for this type of stuff out there, but im not an engineer.
I think you might be refering to "specific fuel efficiency", which is the fuel consumed per unit of power produced. It is commonly quoted for marine and stationary engines, which are both typically constant load and constant speed, so it is more meaningful than for a truck or car.
Another thing with diesels is that they are very efficient at low revs and low load, e.g. when idling in traffic. Unfortunately this also translates to very little excess heat, so they can be cold and miserable as commuter vehicles that idle a lot in a traffic choked city.
Posted 2005-06-12 9:47 AM (#26399 - in reply to #26361) Subject: RE: (relative) fuel use.
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Posts: 560 Location: Mena, AR
I have aa 2004.5 Chevy 1-ton dully, crewcab, with the TTL duramax. I added the Banks Monster exhaust, Air Raid Air Filter, and the PowerChip. Before the add on's I was getting 8-10 mpg pulling a 3 horse, 8 ft wide, 10ft LQ, and 11-12 pulling a 2 horse stock/combo bp with small dressing room. Now I get between 10 & 12 mpg pulling the 3H LQ,(gotten as high as 13mpg on flat ground, no stops) and 12 to 13.5mpg pulling the bp. I get between 17 & 18.5 on the highway, not pulling anything. I stay real close to the speed limit, and I'm not a heavy footed type driver at all. I've been manually tracking my milage for about two months.
The one thing that I've noticed makes the biggest difference is if I keep my rpm's at 2000 or below. The speed doesn't seem to matter as long as I stay below 2000 rpm's. Any kind of hill is a killer for mpg along with starts & stops.
Posted 2005-06-12 10:42 AM (#26400 - in reply to #26399) Subject: RE: (relative) fuel use.
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Posts: 2689
Originally written by bjhouten on 2005-06-12 9:47 AM
I have aa 2004.5 Chevy 1-ton dully, crewcab, with the TTL duramax. I added the Banks Monster exhaust, Air Raid Air Filter, and the PowerChip. Before the add on's I was getting 8-10 mpg pulling a 3 horse, 8 ft wide, 10ft LQ, and 11-12 pulling a 2 horse stock/combo bp with small dressing room. Now I get between 10 & 12 mpg pulling the 3H LQ,(gotten as high as 13mpg on flat ground, no stops) and 12 to 13.5mpg pulling the bp. I get between 17 & 18.5 on the highway, not pulling anything. I stay real close to the speed limit, and I'm not a heavy footed type driver at all. I've been manually tracking my milage for about two months.
The one thing that I've noticed makes the biggest difference is if I keep my rpm's at 2000 or below. The speed doesn't seem to matter as long as I stay below 2000 rpm's. Any kind of hill is a killer for mpg along with starts & stops.
-Betty
Agreed, if you try to maintain your speed on hills and the trannie downshifts - up go the revs, up goes the fuel consumption.
I'd rate the factors; Starts(getting to speed), hills, revs(downshifts on hills), speed above about 57/58, headwind when you're unlucky. About the only thing I know that helps is to allow the speed to drop a bit on the long grades - not to the point of needing to put the 4-way flashers on, but I don't have a problem with dropping a bit below the speed limit.
BTW, those add ons aren't going to pay for themselves in fuel savings, but you knew that already (-:
(relative) fuel use.
