The Andersen WD Hitch User Thread

[dkottum]

Howie, you're going to readjust your Andersen, this is how I understand the Andersen procedure in a nutshell, do you agree? :

1) Be on level ground pavement.

2) Measure inside top of trailer ball coupler to ground.

3) Install the ball mount in the drop bar so the top of the ball is 1 1/2" higher than that measurement.

4) Drop the trailer coupling onto the ball, but NOT to add weight just touching. Lock the coupling latch.

5) Tension the chains evenly until the urethane bushings are each compressed 3/8" to 5/8". (Estimate more or less
depending on tongue weight.)
6) Raise the hitch jack to drop all tongue weight on the ball.

7) Is the trailer level? If low in front, lower the jack to relieve tongue weight and apply more tension. If high in front,
lower the jack to relieve tongue weight and take off tension.

8) With the trailer level and tongue weight on the ball, is there equal drop at front and rear wheel wells of the truck?
If the front is high, go back to step (3) and lower the ball mount. If the front is low, raise the ball mount.
9) When trailer level and truck at original attitude, you're done. Make note of the number of threads left on the chain
adjustment or measure the thickness of the urethane bushing so you can repeat that adjustment each time.

Here's my own observations, everyone will have their own:

The adjustment of the ball mount is in 1 1/2" increments so perfection is unlikely. The important point is to level the trailer, and that the truck does not have a higher attitude in back (lighten rear axle) than front compared to unloaded attitude.

Go to the weight scales if that's what you want to do (not in instructions). If you have satisfactory weights, you're good. If not the hitch will not work for you.

If during the adjustment you break the chains, blow the urethane bushing out, or the bushing is about to blow out, the hitch will not work for you.

If you are convinced there is too much tension on the components and they make break , the hitch will not work for you. This is true of any hitch, but this hitch is new and we have limited experience with it. I have used in in some rough road conditions over my 3700 miles and I see no problems. I like it but I'll keep an eye on it. I'm keeping the urethane bushings away from direct sunlight and the hitch out of weather when stored.

doug k

[AirHeadsRus]

Originally Posted by Sean Woodruff

Well, you aren't really comparing apples to apples. (metaphor intended) (Is that a metaphor?) (BSCE, MBA)



I think your Anderson numbers need more weight on the front axle.




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How much more on the steer axle would be correct Sean?
The difference in the apples is with the Hensley;
Another passenger was in the truck, bed was fully loaded for camping and the 200 pound extra Hensley weight.
I guess with the Andersen set up, if I added the six hundred pounds back in the TV at least 200 pounds of that would show up on the steer axle and be perfect?
But in any case, even with the PP you would like the steer axle to be 3360 pounds like the empty truck?

[Rich of SCal]

Originally Posted by dkottum

Here is my install. Brackets tilted to chain, 3/8" bolt drilled through frame upper side of bracket, 1/2" hole drilled in frame to let outer set screw into lower side of frame. Top front of brackets rounded to clear propane cover and battery box. Compression on urethane bushing 1/2".

I think to get good weight distribution, chains should be tightened with no load on hitch ball, then lower trailer jack to put load on the ball. Will settle to desired trailer and truck level as jack continues to its store position.

Trailer perfect level, truck down 1" in back and up 1/2" in front. I'm okay with that. Handles nicely, quiet, couldn't induce sway moving steering side to side, trailer just followed.

Trailer has 16" Michelin LTX M/S LT225/75R16E on Sendel T02 wheels.

OK, took me 15-20 minutes to refind post number #764. So am posting it here for reference (or until all the "engineers" bury it again. lol). I have ordered my replacement trailer cord for the one I ruined drilling for the setscrew. Good thing I pulled and measured it...it is 10 feet long! So now I want to finish my Anderson hardware install before reinserting the cord back in the frame. I have the bottom set screws in already. I have a 4" 4 sided frame, which it looks like dkottum has also. I just need to add the top bolt. My brackets already have the extra hole.

So dkottum is your setup still working for you? Any advise before I start drilling? Note, I did get one of the first new tilted brackets, so I plan to mount it straight up. Any advise appreciated.

[AirHeadsRus]

Rich,
I mounted mine exactly like the instructions said. I did look at it tilted back at the top but went with the instructions saying mount straight up and down. . I used the set screw with a slight indention drilled in. I have had no issues with the hitch or bracket slipping.
Joe

[dkottum]

Rich, that photo is my Tundra for a short time, I now have it on a Ram.

My frame is 5" (actually slightly under which allowed me to tilt the brackets). I assume you have the 4" frame brackets, or should have.

Before you drill, using the Andersen bolts tighten the bracket tightly to the frame, ensuring the most direct angle of the chains. The trailer should also be on the hitch so you have the right distance to set the brackets back (if you screw this up not all is lost, you can lengthen or shorten the chains).

Do all your drilling, or at least start the drilling with the brackets firmly bolted to the frame or you may have trouble with bolt hole alignment when done.

I predrilled the outside bracket in the drill press, installed it all, drilled through the frame so as to start a hole on the inside bracket, took the inside bracket off and finished it in the drill press.

Then assemble it all, turn the outside set screw tight to make a mark, remove the set screw. Drill a hole for the set screw smaller than the set screw itself so it will not go all the way through, then install the set screw.

I could not get a drill behind the frame to drill for the inside set screw, so I just tightened it as tight as I could.

Take your time and think it through as you go.

Before final assembly i touched up all the bare metal with paint, and sprayed it with CorrosionX. The brackets have not moved in 3700 miles.

doug k

[Sean Woodruff]

Originally Posted by AirHeadsRus

But in any case, even with the PP you would like the steer axle to be 3360 pounds like the empty truck?

Yes, that would be ideal.


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[Tino643]

Version two of my custum brackets. Three and a quarter inches longer, two set screw and paint at the same color as a frame. With this setup, I should not have wear and the force on the plate will be strait.... It is, however, in this spring I'm going to give you news ... Sorry for English ....

[Tino643]

[Tino643]

The first one is the orignal and second the custum....

[AWCHIEF]

Tino, those look great. I think the square tube will work out to be better than the round. You have some nice metal working skills.
About your English, it is much better than my French. So you certainly have nothing to be sorry about.

[polarlyse]

It's probably me being anal about it but when I installed my brackets last month one of them somehow was off a bit. Don't know how these things happen but it couldn't have been my fault. It was off about 1" or so from the other side. Yeah, I know it really doesn't matter and I can adjust for it easily but I just felt better correcting it. Today being such a nice day I made the correction and feel so much better now. I had only taken it for a test drive at the time of installation but in Feb. we'll hook up and head south for awhile so I'll get a better feel for it at that time. I think I'll have to remove one link from the chains but I will wait on doing that.

So, I don't need to lay awake at night worrying about this job. It's done.

Oh yeah, and Tino, no apologies needed here. You're english is much better than my french. Your welding skills are very good too. Nice job.
And we've enjoyed several trips to visit Quebec over the years. Love that town.

[HowieE]

Roger

Unless Andersen had a count difference in the number of links on each side I can't envision any way you would have to remove a chain link if the brackets are set back to equal lengths on each side of the A frame.

Remember while Andersen suggest that equal displacement be maintained on each Acme screw that is only a suggestion and not a requirement as the hitch will self center against the combination of tension on the chains as you drive.

Unlike other WD hitches the Andersen applies the WD force along the center line of the hitch rather than the offset per bar that most bar systems are design with.

[Rich of SCal]

Originally Posted by AirHeadsRus

Rich,
I mounted mine exactly like the instructions said. I did look at it tilted back at the top but went with the instructions saying mount straight up and down. . I used the set screw with a slight indention drilled in. I have had no issues with the hitch or bracket slipping.
Joe

Originally Posted by dkottum

Rich, that photo is my Tundra for a short time, I now have it on a Ram.

My frame is 5" (actually slightly under which allowed me to tilt the brackets). I assume you have the 4" frame brackets, or should have.

Before you drill, using the Andersen bolts tighten the bracket tightly to the frame, ensuring the most direct angle of the chains. The trailer should also be on the hitch so you have the right distance to set the brackets back (if you screw this up not all is lost, you can lengthen or shorten the chains).

Do all your drilling, or at least start the drilling with the brackets firmly bolted to the frame or you may have trouble with bolt hole alignment when done.

I predrilled the outside bracket in the drill press, installed it all, drilled through the frame so as to start a hole on the inside bracket, took the inside bracket off and finished it in the drill press.

Then assemble it all, turn the outside set screw tight to make a mark, remove the set screw. Drill a hole for the set screw smaller than the set screw itself so it will not go all the way through, then install the set screw.

I could not get a drill behind the frame to drill for the inside set screw, so I just tightened it as tight as I could.

Take your time and think it through as you go.

Before final assembly i touched up all the bare metal with paint, and sprayed it with CorrosionX. The brackets have not moved in 3700 miles.

doug k

Thanks guys, for the feedback. My frame IS 4", but the brackets have extra holes for a 3" frame. My thought was to drill through the extra upper holes and add bolts there in addition to the set screw holes to keep the bracket from tilting back under tension. I was set to get some extra 5/8" bolts and nuts for those holes. Upon closer inspection, however, I see a couple of problems. For one, that puts the extra bolt holes very close to the upper edge of my frame. But the bigger problem is that there is not enough room for the heads of the bolts or the nuts to turn with both holes having bolts at the same time. So I could drill 2 smaller holes at a lower point like you did, dkottum, but the bracket material is much thicker than my frame steel and I don't have a drill press to use. So I think I will just drill the set screw holes (one left to do) for now and try that before going any further, as you did, AirHeadsRus. Unfortunately, there isn't enough room on the inside of the frame to drill, so those set screws will just have to be screwed in as tight as I can get them, without the drilling. I have already mounted the brackets while hitched up, and I have them so the upper bolts are gouged into the frame material. Hopefully, the set screws will be enough to stop slippage. I will leave some masking tape in place so I can check it for any slippage.

[dkottum]

Originally Posted by HowieE

Roger

Unlike other WD hitches the Andersen applies the WD force along the center line of the hitch rather than the offset per bar that most bar systems are design with.

And that force is applied with a "spring" bar lifting vertically to apply tension. The Andersen chains pull back horizontally eliminating the spring bar.

This is a feature of the hitch that would make it difficult for me to return to a conventional w.d. hitch.

Every few hundred miles with our Equal-I-Zer we would come onto an old segmented concrete highway or uneven pavement that would send pitching and porpoising moves through our truck and trailer. Sometimes so bad we would have to slow or find another route.

I have not driven those same routes yet, but in 3700 miles around the country we have not experienced that porpoising with the Andersen.

doug k

[polarlyse]

Hi Howie. Hope the " storm of the century" didn't make too much of a mess. Personally I came out pretty much unscathed but around us was trees all over the place. My son lives in S. Brunswick and had 2 come down. Lots and Lots of firewood for his wood stove.
I know what you mean but I think I mounted the brackets just a tad too close to the ball and had to crank down on the chains to get the proper compression. I could move them back an inch or two or remove a link from the chain. I will take a look at moving them after I put a few miles on it and see how it rides. And yes, the thread count was different on each side. No big deal but I just wanted to keep things balanced.

[Road Ruler]

My view.....

Conventional WDH's are more sophisticated compared to the Andersen in the way they transfer weight to the front axles. There is more going on than just lifting the rear of the vehicle. There is a very effective twisting/rotating motion that occurs in the hitch head with the torsion bar design.

The Andersen uses a simple lever system that is only linear but does results in some weight transfer. The Andersen design appears to be less effective.

[HowieE]

Originally Posted by Road Ruler

My view.....

Conventional WDH's are more sophisticated compared to the Andersen in the way they transfer weight to the front axles. There is more going on than just lifting the rear of the vehicle. There is a very effective twisting/rotating motion that occurs in the hitch head with the torsion bar design.

Actually they both work the same way by applying a rotational force about the point that the TV receiver attaches to the frame of the TV. The difference is how they generate that force on the shank of the hitch.

Now it is interesting that the principle objective of the Andersen hitch, Sway Control, has slipped aside in the comments of those attempting to discount the hitch and are now centered on WD. While WD is still a consideration in many cases it is not as important as it was 30+ years ago when most were towing with lightly sprung cars. Trucks have mostly replaced cars as the TV and come with much heaver springs sets thus tongue weight no longer has as detrimental effect on the stability of the rigs. Long gone are the days when you headlights analyzed the condition of the telephone wires strung across the road as you drove along without a WD hitch.

For those attempting to discount the hitch lets get back to what is does in comparison to the competition.

This Bees does fly and that is what it is all about.

[Ron Gratz]

For those who are interested in load transfer data and theory --

Front Axle Load Restoration (FALR) is chosen as the indicator of load transfer effectiveness.
For measured front-axle loads, FALR is defined as the amount of load added by application of WD
divided by the amount of load removed by tongue weight (with NO WD applied).
For measured front-axle heights, FALR is defined as the front-end lowering due to application of WD
divided by the front-end rise due to tongue weight (with NO WD applied) .
When the front end is observed to be returned to the unhitched height, the FALR is taken to be 100%.

The data indicate FALR=100% can easily be achieved for low tongue weights.
However, for tongue weights in excess of 1000#, it is not clear that FALR=100% can be achieved.

The curves labeled "FALR Theory" are calculated from: FALR = 100*CT*2*LA*(1+BOH/TTL)/TW/BOH
where
CT = chain tension in #/chain
LA = lever arm from ball center to chain in ft (assumed to be 6.5"/12 per Bruce H.)
BOH = ball overhang in ft (assumed to be 5')
TW = tongue weight in lbs
TTL = distance from ball to mid-point between axles (assumed to vary from 12' for TW=400# to 20' for TW=1200#)

Contributors of data can be identifed by their TW and achieved FALR in the following table:

TW - FALR - Load/Height - Contributor - DataSource

400---100%----hgt.----SteveH------Airforums.com
400----91%----load----Bruce H.-----Lanceowners.com, RV.net, Airforums.com
900----75%----hgt.----gallifrey------RV.net
600----54%----load----hbillsmith-----RV.net
800----50%----load----airheadsrus---Airforums.com
1250---45%----load----housedad-----RV.net
960----43%----load----renojack------RV.net
600----43%----hgt.----zues----------Airforums.com
670----40%----load----HowieE-------Airforums.com

Ron

[slowmover]

50-60% FA restoration, on average: Insert wishful thinking for the balance of the remainder.

.

[dkottum]

No wishful thinking here Red, mine levels the trailer and resets the attitude of the truck. Which makes me wonder why the broad range of results in the table. Although I am not here to prove/disprove this hitch, I post what I know from use. Otherwise take your pick of the armchair experts, who represent most of the thread.

Improper installation/adjustment procedure or inadequate hitch. I noted a couple of adjustment issues on his thread.

Andrew Thomson cast great doubt about the hitch supporting an early contention that the hitch would simply stretch the chains. When he finally tested on a severely modified suspension vehicle, he told us it wouldn't work and posted completely bogus photos as evidence. This comes from the hitch expect.

HowieE is a user of the hitch who has been attempting to get his properly installed and adjusted, but is going against a headwind for assistance. It's winter in New Jersey and perhaps has set it aside to spring (I would). He has a level trailer and light transfer of weight, with little bushing compression. This suggests he simply needs to move his ball assembly in the drop bar to get more weight transfer and bring the trailer back to level. Did he get help? Heck no, Andrew Thomson instead tells him he is getting inadequate weight transfer, suggesting to all the hitch is no good.

Take your pick of the information, I don't think their is any fair resolution from the commercial vendor and am scratching my head about the various tables posted. Thanks to Ron Gratz for posting the chart. The variable seems to be whether these people have set up the hitch properly.

Red' has got his numbers and jumped to a conclusion. My experience with the hitch suggests no-so-quick.

doug k