This is a great question…
Hi iceman. This is the short story (which does not cover every possible “Yeah but…” possibility and turned out to be longer than I planned

): Any alteration to our vehicles, as they came from the manufacture,
may affect warranty claims coverage.
However, it does not automatically “void the warranty”. Voiding the warranty means absolutely nothing will ever be covered under warranty, ever again.
Very few things “void” the warranty. Two examples would be using a vehicle for racing (and being discovered doing so), Salvage titles etc.
On the other hand,
any aftermarket modifications may/will lead to warranty
claims denial by the Dealership and Lincoln, if the modification can be determined (by the manufacturer) to have lead to the problem. Even if the equipment we installed was “factory” equipment (i.e. the Lincoln factory hitch, wiring harnesses etc.)
It may seem like only semantics, but it is an important distinction.
For example: Vehicle owners who have had their windows tinted and later had power window issues have had their warranty claim denied. The manufacturer has claimed the added tint caused a strain on the power window motor (friction). Or that the installer damaged something during the installation etc.
In this case (adding a trailer hitch), any future warranty claims for electrical and/or electronic issues that can be remotely connected to the trailer hitch wiring modifications (even if only remotely connected to it) could
possibly be denied.
And contrary to what some may feel/state on the Internet, in modification cases such as this, the “Magnuson-Moss Act” does not offer any protection.
A possible exception would be if we have our Lincoln Dealer perform the installation. However, according to the equipment and installation, our recourse then may have to be against the dealer, not Lincoln. That’s where warranty claims coverage and denials can become very sticky.
Also…It does not matter if the Service Manager, Tech etc. told us they don’t care, is our friend etc…the final decision on all warranty claims is up to the vehicle manufacturer, not the Dealership Service Department. Especially in the case of costly claims. And most Dealerships won’t be willing to eat the costs on a large warranty claim if the vehicle manufacturer says no.
And keep in mind, I am not implying these types of modifications will always/definitely lead to a warranty claims denial. Or that the Dealer/Lincoln will even notice the modification.
Only that it is possible, and has occurred in the past. So each of us simply needs to utilize the knowledge and make a decision which is best for us.
Again, a long short-story which does not cover every contingency.
Hope this helps and good luck.
