Quote:
Originally Posted by MeteorGray
I once was interested in buying a travel trailer with a V-nose. After all, such a nose configuration works for boats in water; why not trailers in air?
After looking into it, I decided against the trailer because owners reported no perceptible economy gain, and some said that it didn't handle as well in side-winds.
I ultimately decided against it, mostly because the trailer's design had the tongue weight too heavy for my tastes.
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Crosswinds are what matter. Low ground clearance on independent suspension. All edges radiused. Full-enclosed. FE will follow.
Not owning one at present isn’t any bar to start testing:
1). TARE weight of tow vehicle. This can be combined with;
2). Highway FE test of tow vehicle.
— A CAT Scale 45-50/miles from home out on Interstate. Obtain weight after topping fuel tank to auto shutoff. Correct tire pressure to spec (cold read at home).
— On a loop back to the same location, 100% use of cruise control at your choice of 62,3, or 4-mph. Same as when towing. As you know, keeps you right below commercial traffic. The catbird seat. (I’d note accel/decel events plus forced pass).
This is
the optimum MPG. Can be reproduced by anyone. Changes are only temps, winds and traffic volume.
Engine hours against average MPH is the data desired to make judgments.
If you have — or have had — another travel trailer, then the tow vehicle loaded to the same weight value, but unhitched is the real number wanted.
A). What is the percentage drop from the previous? Against what weight increase (per axle)? (Assumes tires are again optimized. Numbers on the book).
B). As TT Towing FE is more about
mechanical deficiencies against an almost universal 40% towing penalty, getting a baseline on:
1]. TV wheel alignment, steering slop, brake drag and engine air handling (is where to concentrate). Verify.
2]. The (not previously discussed) TRIP PLAN. Where to stop (location in same lane of travel) Where to park & how to park. (Easiest egress).
All familiar with your commercial driver experience. Choices all made in advance.
The familiarization loop can be used with stops each time. A rest area. A travel center. A KOA Campground. A WallyWorld truck-friendly (Trucker Path). A 200-mile total loop for testing incorporating these stops. Refining the how-to.
As it’s never obvious until one does it.
Drive one trip leg at a time. Only. (Kills anxiety).
The ideal is steady-state cruise. Any deviation is what kills FE with a heavy (relative) rig. Accel & decel count total per trip. Laid-back attitude. Get there when you get there.
— If a gasser, a vacuum gauge dash mount (time manual control of downshifts versus using rpm).
— A feedback gauge showing percent of engine load. (Least isn’t best overall, but an acceleration strategy is). Otherwise, keep load under 80%.
Obviously, some of this needs a trailer. But the first two scale tickets and two loops won’t. Nor will attending to TV mechanical.
Gear wanted:
— Brake controller. A TUSON DIREC-LINK is current state of the art. It’s better than the ones integrated with today’s vehicles.
— A Hensley-patent hitch. (Hensley brand or improved Pro Pride). Cheap at twice the price for what it does.
— Budget item to convert TT to DEXTER TOR-FLEX axles with disc brakes.
— Budget item to use TUSON Trailer Brake Actuator for Antilock.
The transitions are what matter (accel/decel). Thus the need for average mph against engine hours for a trip.
Total Time Steady State is far less than people expect. Even after cutting idle time, the need to minimize energy use in transitions are the killer.
One can cut the number & degree of steering inputs to a minimum. Same for use of throttle and brakes.
But where the TT design/equipment is obsolete (leaf springs plus drum brakes) there’s a minimum to accommodate them which isn’t THE TRUE MINIMUM.
AFTER these comes aerodynamic considerations. The above are safety-related (loss of control accidents lead the pack for all RVs), as familiarization can be a painful process. Takes 10k-plus miles over a wide variety of year-round conditions encountered.
Commercial driving is a help. A step up. But it isn’t enough to cover the twins of Safety & FE.
Test, and record. Most FE gains around here aren’t being subjected to noise-elimination. Mechanical deficiencies addressed. Baseline performance improvement (the TV can also be improved via wheels/tires, shocks, anti-roll bars, etc).
I “know” what I should be averaging with my rig. And isn’t the 15-mpg average for which I’m called dishonest using a one ton to pull a 35’. It’s 17+. All of the above applies.
You can start today if you desire.
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