Choosing the proper weight distribution hitch

[Musikaldave]

When choosing the proper weight distribution hitch for the tow vehicle and trailer, is it mandatory that the numbers regarding the height of the tow vehicle and trailer be on the money?

For instance, I did a rough measure of my vehicle on somewhat level ground (the hitch itself was level) and I came up with 19-1/4".

For the trailer I came up with 16-9/16 (the driveway slopes a 1/2 inch toward the tounge over the length of the trailer so It's not perfectly level.

When putting those numbers together I'm coming up with a 2-11/16" drop from the tow vehicle to the trailer.

My question is, how much of that difference can I play with and still be in the safe zone. Can I per say be an inch high or an inch low etc?

I appreciate any response!

[Sunline Fan]

Hi Dave,

Ideally, no, but it depends on the hitch system you want to install. If you want to do a dual cam, you want the setup as level as possible or else the bars will back out of the cams when level on the road, causing the trailer to wag side to side, in and out of each cam. If you just want to do a friction sway/WD, then the slight unevenness should be no big deal.

Remember, you only use those dimensions to first set what holes the hitch head goes into on the drop bar. Then, you need to have the trailer hooked up and the whole rig relatively level (and perfectly straight too- so pull it forward straight a few feet to center it).

Hope that makes some sense... In short, you can go it like you have, but the quality of your hitch setup results depends on how level the driveway is/how accurate the measurements are.

[JohnB]

Hi Dave,

I think what you are asking is, how much drop shank do I need? If so you missed a step and if you set it the way you stated you removed too much weight off the rear axle of the truck.

The truck tow ball unhitched should be 1" to 1 1/2" higher then the TT ball coupler with the TT level. You really need to measure this on level ground to make it easier. If you have true flat ground, just not level, then set the tongue jack to to create the bottom of the TT frame to the true flat ground to be parallel and then measure the TT ball height. Ground to inside of coupler.

See here:
TT level






Now the truck squat height


The truck rear is going to squat from the weight so it needs to start higher when unhitched. When you adjust the WD hitch the TV front comes back to unhitched or slightly above. Not below unhitched height. The rear of the truck will squat some, generally in the 1" to 1 1/2" range for most trucks once WD is adjusted. If I knew the truck and loaded TW I could estimate closer.

The truck may or may not be level. WD is correct when the front end is returned close to unhitched weight. The truck rear ends up what it is. Some trucks are real high in the back unhitched, some are closer to level. A truck being level is nice, but not the sole answer to having WD set up correct. If the rear of the truck is back at unhitched height, then you removed too much weight in the back, the front is over compressed or you have a receiver over flexing problem.

The camper should be as level as it can be adjusted on the WD shank once the truck WD is set. You can only adjust 1 hole up or down. If you cannot get right on level then you need to pick which is next best. 1 hole high is not good. Some TT's can aggravate sway being 1" to 1 1/4" or higher. If the holes are 1 1/4 apart and you have either 1/4" high or 1" low, then pick 1" low over 1" high. Once you pass 1/2" high, it is better to be 1/2 low then high.

Being a full 1 1/2" low is not good or better either as the TT axles are not loaded as equal.

TT level is best, next is slight nose down as opposed to a lot of nose up.

Hope this helps. Ask more as needed. Glad to explain more

John

[Davis]

This might be a useful site for you guys:
Largo, FL Trailer Hitch - 5th Wheel Hitch - Trailer Parts