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Andrew T · 08-07-2012, 04:44 PM

First of all I have not interest in any hitch company I just know what we have used over the last 43 years on thousands of combinations. I am pretty aware of the strengths and Sometimes the devil you know.... I am pretty leary about recomending something I have not tried myself rather extensively. For example we put 15000 miles on two Hensley's before we ever installed one for a customer.

I should likely buy an Anderson to try out. It is just over the years I have bought a lot of hitches that I wound up sitting in the corner after some testing. With the Anderson I just can't seem to make sence of it when I do the math, maybe I am missing something.

Take the 34' & Excursion example. To push the front axle of an Excursion down 1/4" requires about 200 pounds of weight. The front axle is just over 16' from the ball that means the hitch needs to exert 3200 pounds of torque on the reciever to transfer that weight. Likely 400 pounds is being transfered to the excursion's rear axle 5' away so that will take another 2000 pounds of torque for a total of 5200 ft pounds of torque on the receiver.

To leverage that torque we have the distance between the ball and the chain attachment on the bottom of the ball mount Likely about 9". So the chains have to pull back with a force of just under 7000 pounds to create the necessary leverage. with that force the bolt through the clevis pin is going to bend and I think the links would also stretch.

We occasionally break a larger link on a conventional torsion bar chain which has 28" of leverage to work with. I don't think the puck that slides up and down in the rear of the coupler was designed to operate with 7000 pounds of force against it. take a good look under your coupler this is not a particularly robust area. Again it might be fine but what happens after 50,000 miles? Underbraking your trailer should still be pulling on the tow vehicle and even without it is a short duration force not a constant.

One other element is that this hitch will always transfer weight in the direction the trailer is pointing. A conventional weight distribution hitch set up properly will always transfer weight to the front wheels of the tow vehicle instead of the outside rear wheel in a turn.

On the other hand I like the placement of the friction pad and the light weight for hooking up and disconnecting.

Just to clarify my concern.

Andrew T

HowieE · 08-07-2012, 06:29 PM

Andy

Your first assumption is pretty close but the math to get it is not. Yes I add about 175 lbs to the front axle with a Reese and Andersen hitch when the front end drops about 1/4 in.

Your assumption that raw torque is all that is at work is not correct. All a WD hitch does is Distribute the Tongue Weight between the front axle of the TV and the Trailer axles. It is greatly assisted by natural return force of the rear springs of the TV. It is not a Moment Arm analysis as you have described.

Keep in mind that the heaver bars of WD hitches only go up to 1,400 lbs. To produce this displacement of the front axle through torque applied at the receiver they would have to be I beams the size of the truck frame and the rear axle would have to be chained down to the ground.

On a very lightly suspended TV in a very sharp turn any WD hitch might cause measurable additional deflection on the outer side of the TV.

idroba · 08-07-2012, 06:57 PM

Andrew: The Andersen is different, for sure. I hope you get to try one out and see what you think of it in person.

I can't see that the torque on the receiver on the TV is any different from that in a conventional WD hitch. Both transfer weight by torquing the receiver and twisting (lifting) the shank of the stinger. I don't see it different on the Andersen. The Andersen twists the entire ball assembly which transfers to the stinger shank to provide the weight transfer. A conventional WD hitch twists the stinger shank due to a lever arm not any longer than that provided by the Andersen, that is maybe 8 or 9 inches maximum. The twist is provided not by the length of the spring bar arms, but by the short difference in height from the top of the bent bar or the trunion height. Andersen uses a different method, but to transfer the same weight, both must torque the TV receiver the same.

Those of us who have used the Andersen have noted no chain stretching, no bending of the clevis pin bolt. In fact Andersen suggests you leave it a quarter of a turn loose so it does not become stuck if you ever want to take it apart. After 2500 miles of towing, the pin bolt on mine turns freely and easily in it's threads.

The urethane bushings compress about 1/4 inch when set up to tow. I guess there must be some figures somewhere that tell how much pressure they must encounter to compress that dimension, but I sure don't know what it is. That would tell you the tension on the chains.

Due to general wear and stress cracks in my 37 year old coupler that I found when I first installed the Andersen (after de greasing the coupler, i saw the stress cracks on the inner cup of the Atwood coupler) I had my coupler replaced. I would bet there are many out there which might have the same issue, if inspected carefully. However, I towed my first 250 to 400 miles on the old coupler with the new Andersen, and saw no danger in doing it. My personal feeling is that the coupler is equally strong in all directions, and since the Andersen puts very little movement on the coupler parts there actually might be less wear on the rear locking mechanism than with a conventional WD hitch. But I have no way to prove it one way or the other.

I feel, but again cannot prove it with any numbers that the stability I note with the Andersen is a result of all the forces being in one vertical line, through the center of the ball and extended ball shank. On a conventional WD hitch, there is a side to side force caused by the push and pull of the spring bars, each offset two to three inches from the ball centerline. That sideways push from one or the other spring bar, or both in combination, has the effect of making the spring bars twist the TV with a side pressure, which is not present on the Andersen. I emphasize that this is speculation on my part. I do know it is a very stable towing combination.

You have gained a lot of respect in the towing business. I hope you get a chance to try the Andersen in person and see what you think. So far, those of us who have used it have run into no issues of any consequence. Howie E has a big 34' rig, I have a smaller 20' one, we are both happy. Something must be right.

AWCHIEF · 08-07-2012, 07:15 PM

Andrew, I would respectfully suggest that you and anyone else that have concerns give Andersen a call. They are very willing to discuss any and all aspects of the hitch with anyone that calls. They have done extensive testing and can supply many of the numbers that some here keep demanding. I am not an engineer and personally could care less about the numbers game. I did not really understand much of the technical information that passed to me when I was shopping for and setting my hitch up.
Buy one and give it a try. They are fully guaranteed and can be returned for full refund if the customer is not fully satisfied. Believe it or not they tell me that not one unit has ever been returned. I personally have never heard or read one negative comment from anyone that has actual real world experience with the Andersen WD hitch system.
I think if you were willing to consider both of these suggestions you concerns would be alleviated.

Andrew T · 08-07-2012, 08:08 PM

I am pretty sure my torque calculations are correct they are simply a function of distance and weight transfered, spring rate actually has nothing to do with it. I have checked them with a strain gauge and they calculate out the same.

A conventional hitch transfers weight to the front wheels because of the reward angle of the ball mount. In a turn the bar on the inside of the turn rapidly looses pressure but the one on the outside which is pointing towards the front wheels rapidly increases in pressure. The net effect is in turns weight continues to be transfered to the front suspension. If the pivot point is 90 degrees to the ground then pressure is transfered ot the outside rear tire. Again a function of direction and distance nothing to do with spring rates.

I am intriqued enough to try one.

Andrew T

HowieE · 08-07-2012, 09:03 PM

Andy

I would have to agree with you if there were no trailer involved and the rear axle was in fact the fulcrum around which the force was applied. Then yes it would be a simple force times distance on one side of the axle equaling force time distance on the other.

Leave us not try and convince one another as it has been over 50 years since my mechanical engineering classes.

As you mention get one and all will be answered. I trust after that you will never sell another Reese. If the Andersen ever fail like this and the many other Reese failures I have had I may consider coming back

purman · 08-07-2012, 10:32 PM

2500 miles and a few to go till home,and still in loving the simplicity of the thing. Not a problem..

StanandLynn · 08-08-2012, 12:53 PM

With several trips under our belt, including returning now from a 2000 miler, we are still very pleased with ours.

AirHeadsRus · 08-09-2012, 02:00 PM

I am now over 2,000 miles towing with the Andersen hitch. I am still very pleased with it however I did have one issue which I do not know what to think about it. On I-81 on the way back to Virginia from Airpocono, I ran into some really nasty weather with very high wind gusts. That was not really a problem until a semi passed me on a bridge right when a very high gust was blowing. I was in the right lane and the truck was in the left. The gust hit the truck which swerved into my lane. I swerved as well and about the same time he pulled up and exposed my trailer to the gust. Before I could digest what was going on the computer on the f-150 took over both the throttle and brakes. It appeared to me in that split second the power was cut and the brakes were applied in 4 short bursts. What ever it did fixed anything that was wrong and no other problems on the rest of the trip.
I assume that was the beginning of sway but the anti sway combination of truck and hitch stopped it cold. It was nice to have that working for me as I was more concerned about the truck pushing me into to guard rail.

AWCHIEF · 08-09-2012, 02:20 PM

Glad to hear the Ford F150 anti-sway system actually works. Hopefully I will not have to test it on my F150 anytime soon.

dkottum · 08-09-2012, 03:59 PM

I have read two stories about the F-150 sway control. One that it applied only truck brakes to control sway, and another that it also braked the trailer.

Anyone know?

This in combination with the Andersen Hitch is interesting.

doug k

idroba · 08-09-2012, 04:28 PM

My 2012 Jeep Grand Cherokee Overland also has trailer sway control, but I have not had any indication that it worked or not. The Andersen seems to do any control needed, but my experience is only with trucks passing me on the Interstates. Absolutely no push, pull, or any reaction from my rigs.

Oh, my Jeep did not come with a built in brake controller, so whatever it does would only be to the TV itself.

AWCHIEF · 08-09-2012, 06:21 PM

Doug, if I understand my owner’s manual correctly it only applies the TV brakes, but there is more to the system than that. It also controls the throttle. The combination of the two helps to control the sway. The factory trailer brake control also works with the SYNC system to control the trailer brakes using integration with the onboard computer rather than relying on magnets, g-meters or hydraulics as some other brake controllers do.

HowieE · 08-09-2012, 06:46 PM

If the automatic sway control on the TV applies the Brake Lights it would apply the trailer brakes also since that is the signal that the trailer brakes work off. Now that said that signal would be of such short duration that it is questionable what effect it would have on the trailer

SteveH · 08-09-2012, 06:57 PM

Has anyone heard before of the F150 anti sway system ever being activated with any other type of hitch?

AirHeadsRus · 08-10-2012, 10:24 AM

Quote:

Originally Posted by SteveH

Has anyone heard before of the F150 anti sway system ever being activated with any other type of hitch?

That is a good question Steve. When it activated, it was so subtle and short duration in control had I not known it had this feature, I would have just shrugged it off.

Airslide · 08-10-2012, 10:33 AM

Quote:

Originally Posted by AirHeadsRus

I am now over 2,000 miles towing with the Andersen hitch. I am still very pleased with it however I did have one issue which I do not know what to think about it. On I-81 on the way back to Virginia from Airpocono, I ran into some really nasty weather with very high wind gusts. That was not really a problem until a semi passed me on a bridge right when a very high gust was blowing. I was in the right lane and the truck was in the left. The gust hit the truck which swerved into my lane. I swerved as well and about the same time he pulled up and exposed my trailer to the gust. Before I could digest what was going on the computer on the f-150 took over both the throttle and brakes. It appeared to me in that split second the power was cut and the brakes were applied in 4 short bursts. What ever it did fixed anything that was wrong and no other problems on the rest of the trip.
I assume that was the beginning of sway but the anti sway combination of truck and hitch stopped it cold. It was nice to have that working for me as I was more concerned about the truck pushing me into to guard rail.

Great feedback on new technologies.. glad to hear it worked out.
Im sure that would have been the perfect storm for under hitched / dated vehicles.

Vinnie

purman · 08-10-2012, 04:28 PM

Where is the pressure on the ball??

As you can see in the pictures of my ball, (which now has 3000 miles on it) There is some wear on the back of the ball, but most of the wear is on the side back on both sides, which doesn't hit the ball lock, as so many are worried about.

also, you will notice wear on the top front of the ball, not the back!!

Now some of this will depend on the wear of your coupler. Mine is over 40 years old. Others my have different wear on their ball,

(don't go there) It would be good to see some pictures of them.. Stay out of the gutter please

So if you get a chance post some pics..

ROBERTSUNRUS · 08-10-2012, 04:42 PM

Quote:

Originally Posted by SteveH

Has anyone heard before of the F150 anti sway system ever being activated with any other type of hitch?

Hi, is this a praise for Ford doing it's job, as per design, or is it to try and find fault in a new hitch?

SteveH · 08-10-2012, 05:36 PM

Quote:

Originally Posted by ROBERTSUNRUS

Hi, is this a praise for Ford doing it's job, as per design, or is it to try and find fault in a new hitch?

Not trying to find fault with anything, or praise anything. If I was trying to do either, my intentions would have been clear and no one would have asked, I guess.

It is interesting, however, that this is the first time I have read about the Ford stabilization system kicking in. May not actually be the first time, just the first time I have read about it. Now, if it in fact IS the only time it has happened, then I would ask why?