Shift weight to tow vehicle with Hensley

[wildwoodrver]

I've got to shift a few hundred pounds onto my Yukon from the Airstream. What adjustments to the Hensley Arrow will accomplish this?

Thanks.

[dznf0g]

What process have you used to determine your weight needs? The answer is to crank down (pull up) the jacks, but that may not be the appropriate answer here, without knowing all the weights and heights involved with a proper setup. Do you have more info to share?

[HowieE]

When setting up a WD hitch the object is not to just shift a given amount of weight from the trailer to the TV. It is rather to transfer some weight that would normally be carried by the rear axle to the front axle. The amount is a function of the tongue weight of the trailer and the spring system of the TV.

What you are attempting to accomplish is to at least return the weight to the front axle that the trailer reduced by the cantilevering effect of have applied the trailer weight behind the rear axle. This insures the steering system is in a normal configuration and improve sway control that would be reduced by the reduced weight on the front axle.

I generally look for a 60/40 ratio of compression on the rear and front axle as measured to the fender wells of each axle. Place masking tape on each fender and measure the height straight down through the center of the wheel. Mark a line on the tape and hook up and remeasure. Make adjustment to your WD system until you have the relationship you are after.

[wildwoodrver]

The rig has always towed and handled fine. With the addition of four AGM batteries for the solar package, i now weigh 3,600 #, perfectly divided 1,800 left and right on my 3,000 GAWR axle. I would like to shift as much of the 600# to the tow vehicle as I can.

Is it just a matter of lifting the Hensley spring bars ?

I don't want to spend the $ on weighing again until I'm pretty sure I've shifted the weight and also accomplished weight shift to the steering axle (in another thread)

Thanks.

[wildwoodrver]

I'm afraid the automatic level control on the Yukon will mess up the measurements you suggest.

Thanks.

[dznf0g]

Originally Posted by wildwoodrver

I'm afraid the automatic level control on the Yukon will mess up the measurements you suggest.

Thanks.

Not if you remove the fuse. I just got out of an Escalade EXT. I hitched per my instructions in the other thread on that one as well as a Yukon XL Denali in the spring of '11.

[dkottum]

The idea of shifting weight to lighten the trailer is not the purpose of weight distribution bars. It is to equalize the tongue weight put on the hitch, among the tow vehicle and trailer axles so that the front of the truck is not too light for safe handling, and the back of the truck is not overloaded.

It is quite possible and dangerous to lift the bars enough so the tow vehicle rear axle is too light for adequate traction. In theory the tow vehicle rear axle could be lifted off the ground with the weight distribution bars. Yikes!

No weight distribution adjustments should be made without measurement of the tow vehicle front and rear fender height to ensure they have been moved equally. Or more accurately, using weight scales to equalize weight distribution.

doug k

[danlehosky]

I once saw a picture of a late 60's Toranado towing with a WD hitch with no back wheels on the car. I believe it was on this forum but I can't find the thread. The weight had been shifted so drastically that the trailer and the front drive vehicle wheels were the only wheels on the ground.

Dan

[Airstreamer67]

It seems that picture was from a hitch manufacturer's ad demonstrating the effect of weight (re)distribution.

[HowieE]

Originally Posted by danlehosky

I once saw a picture of a late 60's Toranado towing with a WD hitch with no back wheels on the car. I believe it was on this forum but I can't find the thread. The weight had been shifted so drastically that the trailer and the front drive vehicle wheels were the only wheels on the ground.

Dan

Yes that picture was an ad using a Oldsmobile Tornado. It was just that an AD and did not represent anything that could be repeated on the road.

You have misunderstood the function of a WD hitch. They are as stated above only to used to return some of the tongue weight to the steering axle. Keep in mind in doing that a WD hitch INCREASES the weight on the trailer axles also. Yes the tongue weight is split by reducing the rear axle weight between th front axle of the truck and the trailer axles. That ratio will be a function of the distances between the hitch and those axles.

The only way to reduce the weight on the trailer axles is to lighten the trailer.

[dznf0g]

In fact, the OP's owner manual states that the rear fender height should be the same after WD as before hitching up. I DISAGREE WITH THIS. IMO, the front and rear fender height should be reduced by equal amounts after WD setup (in a perfect world). If I were to hitch up my 950# TW AS and have the same rear fender height after WD, I would have far too much weight on the front axle of the TV and not enough on the rear Axle.
On a 1/2 ton, with loaded AS and TV, I get about 1" "settling" on the rear fender height and about 3/4" on the front, verified by scale readings. (as a general rule)

[dkottum]

Surprised Hensley would have you adjust fender heights that way. That's wrong because it suggests all the weight shifted forward should go to the front of the tow vehicle. That could leave the back of a pickup dangerously light.

doug k

[SteveH]

The owner's manual for my GM pickup states to adjust the WD bars to return the front end of the vehicle to the same height it was before hitching up the trailer. This means moving the tongue weight from the ball to directly over the rear axle. I've had good success with this adjustment procedure, and if you think about it, that's exactly how a truck is designed to carry it's load.

I'm talking about a truck here, and not a minivan, or a sedan, or a sports car, or any other goofy thing some people decide to tow with.

I suggest you check your vehicle's owner's manual.

[HowieE]

There is no single answer as to how to adjust a WD hitch. It is a function of the spring rate of the TV. The important consideration is to maintain the steering geometry of the front axle. Too little or too much transferred to the front axle will cause problems. Too little equals a lose of steering control. Too much will cause tire problems.

I generally try for a 60/40 ratio in depression of the fender heights. This will change depending on the springs of the TV.

[overlander63]

Adjusting WD to shift more weight to the front axle also moves more weight onto the trailer axles, which is opposite of what was desired. That's how it works. The tongue still weighs the same, you are just moving the weight off the rear axle onto the front TV axle and trailer axles. So, adjusting WD bars more to move more weight to the front TV axle will overload the trailer axles even more.

[SteveH]

Yes, that is correct, and for the OP to achieve his desires, he should release the WD bars, removing the portion of the tongue weight from the trailer the hitch has moved back on to the trailer, (only about 1/3 of the tongue weight) but this is not a good thing to do, IMHO.

[dznf0g]

Originally Posted by SteveH

The owner's manual for my GM pickup states to adjust the WD bars to return the front end of the vehicle to the same height it was before hitching up the trailer. This means moving the tongue weight from the ball to directly over the rear axle. I've had good success with this adjustment procedure, and if you think about it, that's exactly how a truck is designed to carry it's load.

I'm talking about a truck here, and not a minivan, or a sedan, or a sports car, or any other goofy thing some people decide to tow with.

I suggest you check your vehicle's owner's manual.

OOPS, I stand corrected....completely missed the header line. I can live with this recommendation....although I think it is incomplete. BUT, and I don't know if you all know this, but automotive Owner Manuals MUST be written at a 6th grade reading level! Kind of hard to make complicated technical issues clear at a 6th grade reading level. One of my first assignments in 1984 as a new hire was to write Buick Owner Manuals. A very frustrating experience. I was always told to simplify sentence structure and use little words!

(A) Body to Ground Distance (B) Front of Vehicle







When using a weight-distributing hitch, the hitch must be adjusted so the distance (A) remains the same both before and after coupling the trailer to the tow vehicle.
If you use a step-bumper hitch, the bumper could be damaged in sharp turns. Make sure there is ample room when turning to avoid contact between the trailer and the bumper.
If you will be pulling a trailer that, when loaded, will weigh more than 5,000 lbs (2 270 kg) be sure to use a properly mounted weight-distributing hitch and sway control of the proper size. This equipment is very important for proper vehicle loading and good handling when driving. Always use a sway control if the trailer will weigh more than these limits. You can ask a hitch dealer about sway controls.