Help with 2006 White Yukon XL Denali -- project rust elimination **stop it before its too late

[VikingTrad3r]

Hi All, My wife absolutely LOVES this truck. She moves the kids multiple times per day.

I keep the truck in excellent mechanical condition.

So far I have not done anything other than a band-aid job at "repairing" rust on the outside of the rear fender. There are a few more spots that require the same attention but when I completed the first band aid job, i knew right away it was going to have to be re-done the right way.

I have just pulled the plastic fender liner off of the rear passenger wheel. looking back out its not very bad. no holes. pictures included.

I am willing to sand, grind, cut if necessary, weld if neccessary, but i want this car rust free and looking top condition. My wife is proud of the car, we sort of feel like we are in an $80k SUV that we paid 5K for and it looks phenomenal and is everything we want in a car. So I want to fix it.

that is the background.

***I am asking for help from those who have gone before me!***

Current Plan:

1. wash with sudsy hot water.

2. sand paint down inside and outside of fender, dremel with sand bit if necessary,
if holes go through, so be it.

3. wash POR 15 marine clean which is industrial wax and grease remover.

4. spray/spritz with POR 15 Metal Prep which *my understanding* is that is like Ospho that will, on a microscopic level, react with the rust, and convert the rust in the pores and seams, to iron phosphate, which is black/dark grey, and is paintable **without any further preparatory work**. Like you are actually supposed to paint right over it after it has dried.


I have seen some people say you need to rinse the metal prep, or, other similar products, before painting. but that causes flash rust. every time i have done this, it causes flash rust. no good.

5. the areas are small enough, and the truck is white, so color match is very easy. i have duplicolor match, I will spray the area right over the metal prepped surface (having dried) and then clear coat it with a 2k clear in a can.

that is the plan.

anybody done this? anybody successfully caught this before it was too late and have the rust repair successfully held for years?




^^ inside rear pass fender looking out


^^ inside rear passenger fender looking out




oitside looking in


outside looking in

 

[VikingTrad3r]

delete

 

[VikingTrad3r]

skip to 7:00 on this video to see how these rust out.

i was trying to figure it out but i now realize that the rust is between two panels where they meet.

never done this before.

a little deflated after seeing this. i am not really up for the cutting and welding this guy is doing.

 

[VikingTrad3r]

after using a Dremel to grind away to paint exposing a nice powdery Rust surface to paint just flaked off, I have some phosphoric acid on the steel right now but using a pic I discovered there was a lot of holes in this panel. They are pinprick size at the moment.

Based on the video above, the VE joint where the outer panel and meet inner fender panel meet in our welded will have a whole lot of Rust sitting in the pointy bottom of the VA. I can see that Rust with a pic through these holes and it comes out as a powder.

I don't think there's anything I can do about this other than maybe squirt some phosphoric acid into the holes and let it just either way converting as much of that rest as possible maybe slowing it down, but I do not think there's much I can do here other than Band-Aid solutions given that I am not a welder.

 

[VikingTrad3r]

that was a futile excercise.

I primed and painted the surface filled the pinholes with body filler and I know it's only going to last a couple months before the Rust pop the paint again.

lame

 

[RED TAHOE LS]

Unfortunately , the vehicle has @ one time been up North or by the Ocean for sometime. Salt or Brine (mixture for ice/snow conditions ) is an enemy for a NON UNDERCOATED vehicle. It always appears on the inside rear panels 1st, where it gets trapped and cannot dry out and starts to rust in the form of blisters. I surely don't want to turn the apple cart over, but there is no cure without a big expense. JMHO and good luck.
David g................