spray foam

[Farmboy]

I just replaced the cab corners on my 86 Gmc, and after coating the insides with por 15, I was wondering if I should fill up the corner with expanding spray foam so no mud/salt or water could get up in there again.  This stuff doesn't shrink so condensation shouldn't be a problem.  I have used this stuff to fix all kinds of things and it is really durable as long as it isn't in the sun.  What do you think?

[VileZambonie]

You can do it just make sure you have some cardboard under there to catch the plops that come out.

[Captkaos]

I wouldn't do it, you won't be able to completely fill it up to be void of any openings and water and sediment will find their way in there...

[Blazin]

Be easier to just pull the plug out every few months and wash it out with water.

[78 Chevyrado]

Sounds like a good idea, except the openings like they said above.   Maybe you could weld up all the drain holes involved with that particular area, then no water or dirt could get in (I'm assuming this would work, correct me if I'm wrong).  Shouldn't be too hard to do since you were able to weld in the corner itself.

[VileZambonie]

Since the factory proved that even if you wash and garage your truck the cab corners Will rot don't be afraid to do it. I've done it and used it on my rockers on my 84 k5. It never caused a problem for me.