Wheel Wells: Undercoating or Paint?

[swanicyouth]

I'm looking for something to cover the grey-brown metal under my wheel wells - this is the part that isn't covered with plastic on a SUV.

Its clean under there. I'm thinking of using undercoating, because I just can't see spray paint lasting long. Usually I clean my wheel wells with a pressure washer, and I'm wondering if undercoating would just get blasted away?

Any experience here?

Any brands of undercoating that harden up and stick well?

AG sells Sprayaway Undercoating for $6... The 3M stuff is almost $20 locally. Is there a difference?

[Becciasm]

Roll on or paint on bed liner. Duplicolor kit at advance, or similar.

Sent from my VS840 4G using AG Online

[Chris's FX4]

I used the 3M Professional Grade Rubberized Undercoating in the rear wheel wells on my old truck. Finished to a semi smooth finish but still had some texture. Held up really well in the 3.5-4 years it was on there. Didn't peel or crack, got a little dirty kind of like Line-X but cleaned easily. Held up perfectly fine to power washing, and the winters and roads of northern Michigan.

Will be putting it on the rear wheel wells of the new truck before winter hits.

[Wes Bremec]

Okay here is the problem with using any kind of coating underneath the vehicles. If any moisture gets stuck behind the coatings it could potentially cause damage where you are not visibly able to see it. This damage I am referring to is potential rust problems due to moisture being trapped underneath the coating itself. I would trust penetrating oils all day everyday underneath my vehicle rather then paint or and undercoating. I got this friend down the street that has been spraying his own penetrating oil brew underneath vehicles for over 50 years. It works because he has got a car that has been threw 12 cleveland winters with not one spot of rust damage.