Mod ideas needed for my enclosed trailer

[Braebyrn]

I would like to improve on the mod that was made for my enclosed trailer and would consider comments and suggestions. I can make it out of fiberglass, sheetmetal, stainless, lexan, etc. These ideas would be for the front and back of the trailer.

If it needs to be pointed, or shaped differently, thats fine. I will be driving another 7000 miles in a week to test them out again.

Also I like the idea of the mod for reducing the space between the truck and the trailer, and would like some discussion on that. I see that the Nosecone company makes custom noses for trailers and also that Wells Cargo uses them. I stopped by the Wells Cargo factory in Idaho a few days ago and took a few pictures. What I don't understand is why they don't go all the way to the bottow of the trailer? Maybe its because of rock chips?

[Braebyrn]

Where can I get a copy of the template to lay over a photo of my truck and trailer? I have seen the link with one over a van, but didn't know if someone had one by itself?

Thanks
Rick

[Braebyrn]

Some interesting articles that I found tonight....... http://www.sti.nasa.gov/tto/Spinoff2008/t_3.html

http://www1.eere.energy.gov/vehicles.../06_clarke.pdf

Just need to figure what would be best for my truck and trailer combo.

[slowmover]

Cap on the tow vehicle if it's a pickup. The closer it matches the trailer height the better.


Huh? The tow vehicle and trailer are more than 30" apart. Treat each vehicle separately is the only choice. There won't be a way to reduce that gap and the trailer needs the space on tight turns. Might as well work on a degree in Redneck by hittin' the boneyard for a shiny ol' chrome wing to mount on the cab. And chicken lights.

Running 75? No way that combination can be handled safely. This is foolishness. The posted speed limit is, itself, too high for a rig like this. A classic example of "speeding, under the limit". And I'd sure like to see proof of better fuel economy at 75 (so would Detroit, Cummins, Peterbilt, etc).

Don't feel the passing trucks as much? Hitch rigging is not correct (and tire pressure on both vehicles is suspect). Where are the scale readings which show the hitch rigging verification?

3-4 mpg better? Questionable record keeping is likely. What is the percentage change is what matters AND over how many miles (and details about altitude, trailer weight, general weather, etc, apply).



This discussion -- enclosed trailer fuel economy improvements -- is too narrow a focus if one is contemplating ROI (return on investment). Trailer towing so significantly changes the dynamics of driving that, for a given trailer and tow vehicle, the best money spent is in perfecting trailer tires, trailer brake performance, hitch rigging, and TV/Trailer electrical. Fuel economy is only a sub-set of Economy and focusing on FE first is putting the cart before the horse.

If one trailer allows for 18 mpg behind a given vehicle, but another allows 12 mpg yet lasts twice as long, has better brakes/suspension and is capable of better skidpad numbers . . . and the use is predicated on only 10k annually (or more, or less), the second trailer is a FAR better choice.

First, what is the best trailer to study? Easy, the U-Haul 6'x6'x12' enclosed trailer. (In private use this trailer would NEVER wear out).

U-Haul: Equipment specs

Short, narrow, close-to-the-ground; outstanding construction and design, rounded edges and corners. Will live forever under abusive conditions. What does it need for better fuel economy? Little, as improved suspension and brakes (independent and disc, respectively) are worth FAR MORE than a nosecone or trailing edge device. One might round the corners/edges more, but trade-offs in capacity must be known first. It must also be suitable for a weight-distribution hitch as proper hitch rigging -- the effect of the trailer upon the tow vehicle -- has more of an effect on Economy than do aerodynamics (the costs of poor road performance).

Then, and only then, do aero aids begin to justify their expense.

Money spent on an off-the-lot conventional trailer should be spent towards safety: hitch rigging, tires, braking, handling, lighting; then longevity (method of storage & maintenance), THEN fuel economy. Build standards are low -- throughout this and the RV industry -- and corrections should be made.

The following should be part of any trailer towing kit:

- SHERLINE Tongue Scale
Sherline Trailer Tongue Weight Scales

- Dedicated Torque Wrench
Ace® Torque Wrench - Specialty Wrenches - Ace Hardware

- Tire pressure gauge (trash low quality ones)
QUICKCAR TIRE PRESSURE GAUGES

- Locking Wheel chocks (if tandem axle)
Fastway OneStep Wheel Chock System for Tandem Axle Trailers and Fifth Wheels

- Laminated wheel chocks (need enough for both vehicles)
LAMINATED WHEEL CHOCK at Material Handling Solutions

- Tires
On The Wings of Goodyear | RV Tires - Tire Selection - Marathon®

- Brakes
Dexter Axle - Trailer Axles and Running Gear Components - 3.5K Disc Brake Retrofit Kit - LH

- Brake Controller
http://www.maxbrake.com/brake-controller.php

- Shock Absorbers
Monroe Trailer Retrofit Kit - Shockwarehouse.com

- LED signal/clearance lamps
Super Bright LEDs ? Clearance, Marker and Tail Lights for Trucks

- Upgrade tow vehicle electrical
http://forum.sounddomain.com/ubbthre...page/1/fpart/1

- MODULITE
Upgraded Modulite Circuit Protected Vehicle Wiring Harness with 4 Pole Trailer Connector Tow Ready Wiring 119176
Information on Modulites

- Trailer brake re-wire
RV.Net Open Roads Forum: Towing: Independent Brake Wire Feed Upgrade

And so forth.

ANY one of these -- dollar for dollar -- is worth more than add-on aero devices. And, if the trailer is at 2500-lbs or above (or at the weight where a weight-distribution hitch is required for a given vehicle [and NONE are exempt, including the heaviest pickup]) then hitch rigging is paramount.

Frankly, a study of how to drive for economy -- while towing -- is time/money better spent than tack-on aero aids. The return is greater, the $$ are lower, and it is subsumed under what truck drivers know as "trip planning". The details of how to accelerate, what pace to maintain, what braking distances, when to get off the road, what kind of roads, etc, etc, are more fruitful.

So here are two questions:

1] In what manner will a blunt-front trailer's performance improve with aero add ons?

2] In what manner will it DECREASE? (for it will)

.

[Weather Spotter]

slowmover:
You seem to think that safety is more important the FE, I agree. But lets keep on topic of helping Braebyrn get beter FE out of his setup.

I think that Braebyrn is working off the beaten path here, good for him!

Trailer towing has room for great FE improvement. I know on my car when I pull our little 5' x 10' open grate trailer my FE sucks. I also tend to notice aero changes more than normal. I like the boat tail on the back of the trailer.

For the front look at ways to reduce the gap if possible. I might try building insulation foam (Dow blue Styrofoam) on the front of the trailer. You can shape it if needed and if you make it to tight it will just break off without damaging the truck pulling it. Try to slope the height of the truck to match the trailer, a long slow slope is better (think Kammback in reverse) to keep air flow attached. You might be able to make a sheet of colorplast come off the truck and rest on top of the trailer, this would keep the air attached but allow the trailer to pivot.

[Braebyrn]

Slowmover,
I follow all of your comments except the tongue scale. I think is a great tool and I should get one.

I use a infrared temperature tool to check the tires for the correct load. It has been my way of leveling the load. But it requires me to drive for about 10 minutes to heat up the tires. Not the best way to do it for sure.

Driving 75 with a wall behind the truck is not smart you are right, but I wanted to see how well the mod worked. I slowed down to 62-64 and found that range worked well too. Tires are cooler too!

I will have to go thru all of the fuel reciepts and post them. Like you stated, Altitude, weather, tire pressures, etc. will skew my results. I drove up passes, flatlands, construction zones, and many other different weather conditions and even the longest cattle herd I have seen. Messy too! The extra crap on the wheel wells and trailer, didn't help me much either.

What can I do different for the hitching for the sway from passing cars or cars passing? I have the load leveler bars, but do not use the sway bar.

But when I added the last boattail, it amplified the sway caused by passing vehicles.

[RobertSmalls]

Originally Posted by Braebyrn

Where can I get a copy of the template to lay over a photo of my truck and trailer? I have seen the link with one over a van, but didn't know if someone had one by itself?

Thanks
Rick

Here's Scania's successful trailer boattail. They would have better aero with progressive curvature, but they wanted to be able to fold the extension flat against the sides of the trailer with the doors open.



A copy of the template: http://ecomodder.com/forum/showthrea...rt-c-9287.html

Examples of the template used correctly, and one example of incorrect usage: http://ecomodder.com/forum/showthrea...zx2-11266.html

[Braebyrn]

Originally Posted by Weather Spotter

slowmover:
You seem to think that safety is more important the FE, I agree. But lets keep on topic of helping Braebyrn get beter FE out of his setup.

I think that Braebyrn is working off the beaten path here, good for him!

Trailer towing has room for great FE improvement. I know on my car when I pull our little 5' x 10' open grate trailer my FE sucks. I also tend to notice aero changes more than normal. I like the boat tail on the back of the trailer.

For the front look at ways to reduce the gap if possible. I might try building insulation foam (Dow blue Styrofoam) on the front of the trailer. You can shape it if needed and if you make it to tight it will just break off without damaging the truck pulling it. Try to slope the height of the truck to match the trailer, a long slow slope is better (think Kammback in reverse) to keep air flow attached. You might be able to make a sheet of colorplast come off the truck and rest on top of the trailer, this would keep the air attached but allow the trailer to pivot.

Is this what I could do on my setup or is over the top too much?

[Weather Spotter]

Your pic adds too much additional height.

Try going from the top of the cap to the front of the trailer (leave enough overlap so it does not fall down when you turn).

[Braebyrn]

Like this?