I picked up a new 16 King Ranch a few weeks ago. I was thinking to undercoat the truck chassis. Has anyone here done that? Would that void warranty?

 

Just curious as to why you want to undercoat?

 

Wouldn't void the warranty unless you sprayed something that caused a failure of some sort. Wouldn't know enough about it to tell you what to avoid.

 

Protection from salt in the winter.

 

I had mine sprayed with Fluid Film. It will not void your warranty. Many people think there's no need because the truck is aluminum, but the frame and related components are steel and they will rust eventually if you live in an area that sees a lot of salt on the roads in the winter. If you're one of those that only keeps your truck for five years or less then it's probably not worth it, but if you plan on keeping it for a long time then I would do it. My last truck (1999 F150) had the spare tire fall off because the crossmember that held it in rusted out. I'd like to avoid that again.

 

The past few winters in NJ were rough. It took a toll on my old 01 Sport Trac that the front of the passenger side running board fell off a few months ago.

 

I plan on undercoating mine as well, but only the chassis underneath. It will not void warranty.

If you ask for a full undercoating where they will start drilling holes in the doors, panels, etc., that's when you usually get in trouble. If you want to do that, wait until the 3yr/basic warranty is over.