About Weight Distribution Hitches...pics etc.

[project]

Bird and Dave.

Bird, My trailer weights 9400 dry and I think the hitch weight is 1100. (this gearbox is the small one). I would like to believe the dealer was more caring about the adjustment, (I doubt it) but I backed the truck up to the trailer and noticed the sag. I did say something about it and the reply I received" you ought to see some of the others" . That's why I'm on this forum to find out what's right.

Dave, I just came in from looking at the hitch head (label reads PRO SERIES)Its at the top setting. Are you saying to shim the "ball " shank up ?? It appears to have room for a couple of shims before running out of thread. I don't see anything else that would take a shim. Am I missing something?

Thanks Tony

 

[Bird]

Tony, since Dave apparently isn't online right now I'll answer for him. NO! He was not talking about shims under the ball. The hitch head (or ball mount) is bolted onto the shank. Some types don't just have the round holes for the bolts through the sides, but have a bolt that goes from the rear forward and you can put shims (washers) on that top bolt between the hitch head and the shank. The more washers you use, the farther back you tilt the top of the ball. You don't raise it; just just tilt it.

From your pictures, that appears to be a Reese hitch, or at least the Reese design, and does not use the shims.

 

[KentT]

Picking up on an early question -- whether the trunnion bars are round or square just depends on the manufacturer. Some think the square ones are more "bullet-proof" in that you don't have spring-loaded pins to hold the trunnion in to the hitch, which can get lost or broken. The round ones have those pins. When researching them, I found the square trunnions to be quite a bit more expensive -- so I went with the round ones for my own use, since I don't trailer that often. I've used a square-trunnion Reese and found it slightly more difficult to hook up than the round trunnion also.

I found my most recent one on sale online at JC Whitney, with free shipping. I think I paid $249.00 for what is regularly $299.00 -- one of the best investments in tools/equipment that I've ever made. Note that this is only the hitch -- not the receiver nor the anti-sway kit. IMO, anti-sway kits only become critical if (a) it is a tall flat-sided trailer (like a camper) catching a lot of sidewind, or (b) you're hauling loads that aren't fairly well balanced side-to-side. I've had no problems with sway at all hauling tractors and equipment on a tandem trailer without one.

I now have a Hidden Hitch (same as Draw-Tite) and it has the washers to shim the shank of the hitch. Each washer essentially moves the bars up or down 1"... Here's a good illustrated set of instructions on how to hook them up, measure, level, etc -- even attaching anti-sway controls.

http://site.drawtite.com/WeightDistributionDualCamSwayControl.pdf

 

[Bird]

Some think the square ones are more "bullet-proof" in that you don't have spring-loaded pins to hold the trunnion in to the hitch, which can get lost or broken. The round ones have those pins.

But not all the round ones have those pins. I had EazLift with round bars and they did not have pins. I'm not sure how to describe it, but you turned the bar at a 90 degree angle to the back of the car to insert it, then locked it in place as you turned it to point back at the trailer.

 

[KentT]

But not all the round ones have those pins. I had EazLift with round bars and they did not have pins. I'm not sure how to describe it, but you turned the bar at a 90 degree angle to the back of the car to insert it, then locked it in place as you turned it to point back at the trailer.

I turn mine 90 degrees also, to insert it, but it is a small spring loaded pin that goes into a groove around the top that holds the trunnion bar up in the hitch.

 

[Bird]

Kent, I know I didn't have any "pin" that I moved or removed, etc., but yes, there was a "groove" I guess you would call it in the top end of that EazLift bar. My parents had the same kind of hitch. They got theirs in 1971 and used it for 4 years. The EazLift that I had was one I bought in 1975, but only used that particular hitch for 2 years. So, since it's been 30 years, it's possible that I might have forgotten some details.

 

[Redbug]

Schism, Orezok and KentT...Those are some great links you posted! Really good info, some stuff I did not know, and more choices out there than I realized.

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Tony...I took some pics to show you what I mean about adjusting your WDH using the shims.

1st pic...Shows me pointing to the shims. The shims, (washers), go onto a bolt like piece which holds them in place between the shank and WD head. You can vary the number of shims in there, depending on your vehicle/trailer combo.

2nd pic...Shows how the shims cause the WD head, (and trailer ball), to be angled...that causes the WD spring arms, (when attached to the head), to be aimed more at the ground or downward. Since the WD spring arms have more distance from the trailer tongue, you can draw up further on the chains. That makes the spring arms take more weight.

3rd pic...Everything assembled, now take notice how the WD head is angled on the truck, (like it's looking more at the ground), and the chains are pretty short, but not enough to let the spring arms hit the trailer tongue when turning. By angling the WD head that way with the shims...and shortening the chains...it causes more trailer tongue weight to be transferred to the front wheels of your truck. It is in effect a fulcrum! Now also take notice how the dog is angled from the truck...

 

[Bird]

Nothing like good pictures to get a point across. Good show, Dave.

 

[Redbug]

Thanks Bird. I've learned more from you guys than you can imagine. Just sharing a little of what I know, too.

 

[project]

Dave and Bird, Its more clear about changing the angle of the WD head. Dave I have a different setup than yours. I think mine is a Draw-Tite Pro Series. The labels only show Pro Series. As I checked the angle of the head, mounted in the truck receiver, It very close to 90 degrees,(level, straight out from the reciever)) possibly turning up slightly. (Dave, opposite from your photos) By rotating a six sided washer,(different length sides) one on each side of the head, it will create different angles. If I angle it down, will this raise the rear of my truck up when I mount the WDH? My goal is to reduce the truck sag while keeping the trailer level. Dave, I learned a lot from your post and all the replies you received. I should forward this entire thread to my dealer.

thank you, Tony

 

[Egon]

I have had two different WDH as the first one broke an arm.

The first had washers and bolt for leveling the ball. The second had a two multisided plates that were rotated for levelling.

 

[Redbug]

Tony,

To answer your question...Yes.

You need to rotate your six sided shim washer to adjust WD head angle looking more towards the ground. Then, with your trailer jack cranked down on the ground supporting all the trailer weight, (and maybe more), attach the spring arm chains to your trailer tongue. Shorten the chains up! Then crank your trailer jack up...till it's off the ground. I'll bet your truck will be level! Your truck will then have a lot more weight transferred to the front of your truck.

You just have to play around with the WD head angle, and the number of chain links to take up...in that order.

 

[Reg]

Probably should have started the explanation with a clarification.
Weight Distributing Hitch is a misnomer, the weight doesn't get distributed at all, it stays right where it is.
Then lead into the explanation of a LOAD RE-distributing hitch...
(-:

 

[Redbug]

In reality that's true Reg...The weight is really the same pulling down on the truck's rear end. But what a WDH really is...a fulcrum. When weight causes the truck's end to sag, that puts more stress on the on the spring arms. The spring arms try to keep the truck/tongue/trailer in a horizontal line at equilibrium. With more weight added, the horizontal line becomes more like a V...looking at the truck/tongue/trailer combo. The spring arms in turn react by flexing to return the truck/tongue/trailer back to equilibrium...the straight line. The spring arms rotate the shank in the truck's reciever to make everything straight again. It used the weight against itself. Whew, that was a mouthful.

About fulcrums...here's a an interesting real life question...
A pulley is suspended in a tree. A rope goes through the pulley block and back down to the ground which is attached to a 100 pound weight. You lift the weight using the rope going through the pulley. How much force, (pounds), is exerted on the pulley in the tree to lift that weight?

 

[Kendall69]

How much force, (pounds), is exerted on the pulley in the tree to lift that weight?

100 pounds

 

[Skyco]

I'll add that getting the right weight spring bars is crucial. They need to be matched somewhat to the trailer toungue weight. Unlike the head itself a higher rating isn't necessarily better. IOW if you have around 750 tongue weight get the 750 bars, if you have 1000 get the 1000 bars. Too stiff of bars and ride is tense, to weak and it is too bouncy. I have a toy hauler with very high tongue weight since all the RV stuff is up front. A buddy had a light weight trailer, we were camped together with both units and discovered his bars were much stouter than mine- we swapped and we are both much happier, it does make a difference

 

[KentT]

If I understand how they operate correctly (and I think I do), the weight actually does get distributed -- i.e. load is reduced on the back axle and transferred to the front axle.

To make this easier to visualize - picture a "hard connection" between the trailer and the truck's hitch -- no up or down movement is possible. The weight of the trailer tongue would be spread to both the front and rear axles of the truck. The rear axle would no longer be a fulcrum, but would be one of two "pressure points" instead.

If you don't think a WD hitch really distributes weight -- try adjusting one too tight and you can literally lift the back tires of the truck off the ground....

 

[Egon]

back tires of the truck off the ground

Years back there was an add for front wheel drive showing the back wheels off the ground!

That has been mentioned here before.

 

[Redbug]

Answer to fulcrum/pulley question...

How much force, (pounds), is exerted on the pulley in the tree to lift that weight?

Answer...200 pounds. The weight itself weighs 100 lbs, and you have to exert 100 lbs of force on the rope going over the pulley to lift the weight. Both sides total 200 lbs force on the pulley.

 

[Kendall69]

100 lbs.

Howstuffworks "How a Block and Tackle Works"