Originally Posted by AS_X5
-- snip -- lease on a 2016 X5d turbodiesel, and the dealer installed a new-fangled hitch (Invisihitch?) -- snip -- rated to 6,000#, with 600# tongue weight. -- snip -- does not accommodate weight distribution system (WDS/sway control). Looking at an adapter plate that turns it into a standard 2" receiver so we can use the old ball mount and WDS ball. -- snip --
You may have a problem - note the distance from the plate bolting surface to the ball center line. It is a very tight configuration. Then calculate the distance the WDH ball will be from the plate surface when the adapter and WDH are installed. My guess is that it is about 12in more than the OEM location. Every inch added increases the lever arm and therefore the loading that is placed on the ball mount connection to the hitch cross member.
Now, you may not have a problem, if the connection design is over engineered and over built. That is not likely, but maybe.
Suggest you see if the connection is bolted or welded to brackets welded to the cross-member. If it is bolted, you can have an adapter constructed that locates the 2x2 receiver under the vehicle and with a shorter lever arm. The intent would be to keep the ball as close to the bumper as possible while still having enough clearance for the trailer tongue when making a tight turn. Note that the hole which locates the WDH ball mount in the receiver can often be moved to a location on the shank that reduces the lever on the assembly. Same concern with turning clearance applies.
You may be better off to take the X5 to a hitch shop and have a Curt or Draw-Tite hitch with a standard 2x2 receiver installed in place of the OEM hitch. Would cost about $850 +/- $250. Not sure how much the change would impact the end of lease residual value. Might require the OEM to be replaced.
Interested to hear how this works out for you. Any chance you have run your prior rig across a CAT scales. We are challenged to manage the 600# tongue weight limitation and would expect that might be an issue for you as well.
Good luck with your investigation. Pat