New Andersen WD hitch

Hi John,

I can respond to some of your points -- but not necessarily in the order in which you made them.

JBarca wrote:
Chains towing the camper When the TV is stopped or rolling forward at low speed, the chains are pulling the camper. The chain force is high enough that is it pulling the camper forward and seating the tow ball into the latch side of the ball coupler. Clearance exists between the ball sphere and the front part of the coupler that normally pulls the camper. The rolling resistance of the camper on the 28.3" OD tires on concrete or black top is less then the chain force under these conditions.

Let's assume each of the two chains is pre-tensioned to 2000# and each chain is parallel to the longitudinal axis of the TT. The chains would be pulling rearward against the spreader plate with a combined force of 4000#. With the TT at rest, the tension in the chains would cause the ball coupler to push forward against the ball with a force of 4000#.

When being towed on level ground at 70 mph, the combined aerodynamic drag and rolling resistance acting on a TT probably would be less than 1000#, but let's assume it is 1000# for arithmetic simplicity. This means, as your title suggests, the chains would be towing the TT.

The combined chain tension of 4000# now is divided into 1000# pulling forward on the TT and 3000# pushing forward on the ball. IMO, it is highly unlikely that there would be any "banging" of ball against coupler. It looks to me as though the ball always will be pre-loaded in the forward direction.

Tow ball towing the camper There may be a point where the wind drag on the front of the camper or up hill (gravity) loads increase enough that the TT drag is higher then the WD tension in the chains. In this case the TT would shift backwards by the clearance in the coupler when the wind drag force overcomes the WD chain force. The tow ball leaves the coupler latch and now becomes seated into the front part of the ball coupler. The TT is now pulled by the ball coupler.

Now, let's assume you actually could tow a 10,000# TT up a 6% grade at 70 mph. This would result in an additional towing force requirement of 600#. The previously calculated forward force on the ball would be reduced from 3000# to 2400# -- still sufficient, IMO, to preclude any "banging" of ball against coupler.

What we do not know yet, is on a 1,400# TT tongue weight, 9,200# GVW TT does the wind drag or up hill drag ever get high enough to let the ball coupler tow the camper? And any guesstimate on what speed that may be? I picked those weights only because they line up with my camper. The issue can occur under other TV and TT combos as well.

IMO, if each chain is pre-tensioned to 2000#, it is highly unlikely that the combination of wind drag, uphill drag, and rolling resistance will ever result in the ball pulling forward against the coupler.

The high load on the coupler saftey latch is a large concern. If the TT seats and reseats back and forth constantly as you tow down the road, the fatigue on the coupler saftey latch is something to think through.

IMO, the TT will not seat and reseat back and forth. However, I do think that coupler manufacturers should be asked to comment on any possible consequences of operating with the coupler constantly pushing forward against the ball.

We understand how it has the ability to distribute weight. How effective it is and sensitive it is is another question.

IMO, your previous post gave a excellent analysis of how much WD torque might be generated by the Andersen hitch. The new hitch is rated for 1400# tongue weight. I doubt that a combined chain tension of 4000# would provide sufficient WD torque for a 1400# TW. It would be good if Andersen could provide some before and after axle load data.

Ron