Figured I would post here as you all have similar trucks to mine.

I have a 2002 F250 with 84k miles on it.
I have owned for 3 years, bought it with 56k on it.
When I bought, the bed wasnt perfect, could tell it had a lot of use but didn't see significant rust damage by any means.
The truck had a 5th wheel hitch which was removed.

I had it undercoated and a spray in bed liner installed.
It is kept clean and washed regularly including undercarriage.

So this weekend I stepped on a spot in the bed and heard a crunch and it was soft....
It is a section no much bigger than my shoe that is between two of the bolts of the bed near the left side wheel well.
I look underneath....totally rotten. Infact, the whole strip about 10 inches wide across the truck bed directly above the axle is not in good shape. The rest of the underside of the bed is just fine.

What gives? Any idea what just this area is rotten and the rest looks brand new?

I am taking it back to Woodhouse Ford in Blair, NE where I bought, they will hopefully help me out.

Just was hoping to get some opinions.

Truck is too new and too well maintained for any kind of rust like that. The body doesnt have a bit of rust from tip to tip other than this.

 

Andrew my guess is that there must have been some rust and maybe even water in there when the spray in liner was installed. I have never heard of that being a common area for rust, especially in a truck as new as yours. Is it possible that the rust is anywhere near where the 5th wheel was mounted? Its possible that took its toll on the steel there and probably rubbed through the paint and primer, leaving that metal even more exposed.

? just a few ideas. You can always cut that stuff out and weld a patch in there and put some do-it-yourself spray on liner to make it match.

Andrew OT- do you recognize the name Laughridge?

 

Well if it was anywhere near them bolt holes from that fith wheel, you might have a problem getting them to fix the problem . If its not near them bolt holes, you might have a good arguement. Some pics would be good?

 

The only hole from the 5th wheel was for the hitch itself, that is a ways away from here.
Maybe where the support for the 5th wheel was between the frame rails rubbed at the bottom of the bed?

 

my guess would be they didnt spray inside the body cross members yet pluged the holes so water couldnt drain....it should be a must do..it is up here...but they only care about the $$..not the end results..

 

I agree with Lisa. I'll bet that moisture somehow got trapped under the bedliner.

 

I have almost 300k on mine and the wheel wells are rusty. Lots of rust spots. The bed is fine though. What kind of spray on liner do you have? I know some offer a life time warranty. Check it out

 

Yep. I think she nailed this one. Any moisture that can sit between either the bedliner or undercoating and the bed will promote rust and severe corrosion. Check both the bedliner and undercoating around the bad area to see which one lost it's adhesion. Then check the rest of the bed for other areas of poor adhesion. This is the exact reason prep work is so important before any coatings are installed.

 

The bedliner was a spray in. It turns out the issue was from the 5th wheel hitch. Before I owned the truck, it had a 5th wheel hitch, where the cross-member went between the frame rails it rusted out the bed from below. It was due to dirt and moisture being trapped between the 5th wheel support and the bed and never drying.

Anyway, as it turns out my ball joints were also going bad so I traded the truck for a 2008 w/ 6.4L.