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slowmover · 06-11-2012, 12:42 AM

12-15% tongue weight [TW] is the RV standard. Less than that isn't as effective, and up to about 18% is good (old SAE papers).

A weight-distribution hitch [WDH] is the requirement by the big automakers even on one-ton diesel dual rear wheel pickups past around 350-500 lbs TW. TW is not static . . that lever arm extending back to the axles can exert many thousands of pounds of force in adverse circumstances. A WDH has two jobs:

1] Restore the Front Axle to it's unhitched weight when activated.

2] "Distribute" the remaining TW between the tow vehicle and the trailer.

The effect is to keep the steering (especially) close to stock vehicle feel/action (some level of understeer), and for braking & handling otherwise to remain close to stock.

The addition of weight to the trailer axles helps that vehicle as well, especially in braking.

A 600-lb TW might wind up as 150-lbs back onto Front Axle, and the remaining 450-lbs spread between Drive Axle and Trailer Axle as 270-340-lbs on Drive Axle and the balance back to the trailer.

Obviously, a tow vehicle drive axle carrying around 300-lbs trumps 600. But the Steer Axle not being lightened is the key.

And, yes, a well-sorted WDH will certainly help mpg . . less movement inside the lane, less reaction to crosswinds, etc.

The addition of anti-sway devices (the right ones, not the old friction bar type) will definitely be noticeable.

There is new design in WDH hitches, and it's simplicity is appealing:

Andersen WDH

An apt discussion here.

That and LT tires (not ST tires: unacceptable failure rates on tires made on obsolete equipment [is the current surmisal]) would be high on my list for reliable trailer performance behind such a marginal tow vehicle (tall, short wheelbase and underpowered).

Same for a TEKONSHA P3 Brake Controller (at minimum). That's one helluva long trip.

Trailer tires should always be at cold sidewall maximum pressure. That and lug nut torque value is what I check before ever moving the trailer. Every time.

Trailers have a tendency to want to pass their tow vehicle. However well loaded they'll move around quite a lot in the lane. A good WDH damps this tendency greatly. It's noticeable at the steering wheel and at the fuel pump.

Lessened driver fatigue is the real MPG secret, and WDH plus best brake control adds immeasurably to this.

.

06-11-2012, 12:42 AM	#25 (permalink)
slowmover Banned Join Date: Oct 2009 Location: Fort Worth, Texas Posts: 2,442 2004 CTD - '04 DODGE RAM 2500 SLT Team Cummins 90 day: 19.36 mpg (US) Thanks: 1,422 Thanked 737 Times in 557 Posts	12-15% tongue weight [TW] is the RV standard. Less than that isn't as effective, and up to about 18% is good (old SAE papers). A weight-distribution hitch [WDH] is the requirement by the big automakers even on one-ton diesel dual rear wheel pickups past around 350-500 lbs TW. TW is not static . . that lever arm extending back to the axles can exert many thousands of pounds of force in adverse circumstances. A WDH has two jobs: 1] Restore the Front Axle to it's unhitched weight when activated. 2] "Distribute" the remaining TW between the tow vehicle and the trailer. The effect is to keep the steering (especially) close to stock vehicle feel/action (some level of understeer), and for braking & handling otherwise to remain close to stock. The addition of weight to the trailer axles helps that vehicle as well, especially in braking. A 600-lb TW might wind up as 150-lbs back onto Front Axle, and the remaining 450-lbs spread between Drive Axle and Trailer Axle as 270-340-lbs on Drive Axle and the balance back to the trailer. Obviously, a tow vehicle drive axle carrying around 300-lbs trumps 600. But the Steer Axle not being lightened is the key. And, yes, a well-sorted WDH will certainly help mpg . . less movement inside the lane, less reaction to crosswinds, etc. The addition of anti-sway devices (the right ones, not the old friction bar type) will definitely be noticeable. There is new design in WDH hitches, and it's simplicity is appealing: Andersen WDH An apt discussion here. That and LT tires (not ST tires: unacceptable failure rates on tires made on obsolete equipment [is the current surmisal]) would be high on my list for reliable trailer performance behind such a marginal tow vehicle (tall, short wheelbase and underpowered). Same for a TEKONSHA P3 Brake Controller (at minimum). That's one helluva long trip. Trailer tires should always be at cold sidewall maximum pressure. That and lug nut torque value is what I check before ever moving the trailer. Every time. Trailers have a tendency to want to pass their tow vehicle. However well loaded they'll move around quite a lot in the lane. A good WDH damps this tendency greatly. It's noticeable at the steering wheel and at the fuel pump. Lessened driver fatigue is the real MPG secret, and WDH plus best brake control adds immeasurably to this. . Last edited by slowmover; 06-11-2012 at 12:56 AM..