Only the Atwood 88xxx series couplers are incompatible with our Weight Distribution Hitch. ALL OTHER Atwood couplers are fine (80xxx, 81xxx, 82xxx, etc).  Although we have some customers who are using the 88xxx series without problem, for the best solution our official stand is this – if you have one, change out your coupler. Luckily it is not a common coupler, but it is popular on Airstream trailers. 

Below is our official announcement:

With thousands of units on the road over the last 2 years, we have had tremendous success and customer satisfaction with the Andersen “No Sway” Weight Distribution Hitch.
 
A few months ago we heard a few reports of an issue that was specific to the Atwood 88000 series coupler. Although there were only about 10-12 reported cases, it was enough to concern us, and we performed some in-house testing of the coupler.
 
The issue: A few customers reported the potential of the Atwood 88000 series coupler to come unlatched over time due to wear. 
 
NOTE: The Atwood 88000 series (stamped on the coupler as "Atwood model 88xxx" - xxx being any digits) is the ONLY coupler design in the RV market we have found that has this potential issue. All other Atwood couplers work fine. The similarly designed Marvel coupler also works just fine with the Andersen WD Hitch.
 
What we have found so far:
We have been performing in-house testing of the Atwood 88000 series coupler, as well as consulting with engineers and RV Technicians. At this point we have not experienced the unit unlatching, but we can see there is the potential for the possibility of this happening over time with the Atwood 88000 series so we are taking the issue very seriously. From the reports given we were told that it is something that happens over time, not immediately.
 
What can happen:
Because of the particular design of the Atwood 88000 series coupler, there is a lot of extra movement inside the coupler as compared to other couplers on the market. When combined with the reverse pressure that our Weight Distribution system places on it, over time, the slack in the internal mechanism of the some of these couplers slowly works its way backwards trying to unlatch from the top 'fin' - and eventually it can wear the fin down enough that it does not fully latch any more. 
 
The solution: 
At this point our official position is that the Atwood 88000 series coupler is incompatible with our Weight Distribution Hitch, so the ONLY current solution we endorse is to replace the coupler. A good quality and sturdy replacement is the Atwood MPD 81911 coupler (seen below). However any coupler other than the Atwood 88000 series will work just fine. We have checked with several welding shops who told us that it would take about 1 hour of shop time to change out the coupler, averaging about $60–$100 in shop fees.
 
Other solutions: 
Although we have heard of a few Airstream owners who have had some success with modifying the latch mechanism and greasing the paw and ball, Andersen Mfg. does not officially endorse any solution other than replacing the coupler itself.