Maintenance on 09 Silverado

I just bought a new 09 Silverado 1500. Being somewhat of a mechanic I know how hard the northeast can be on a vehicle, expecialy the frame. I have noticed the Silverado has tubes conecting the rear section of the frame. I have found that dirt and grime can build up in the tubes and create corrosion and rot out your frame. I have cleaned them as much as I could but still see dirt getting into the tubes. My question is:

Is there any way to prevent dirt building up in the frame tubes? can you purchase something to prevent this ?

is there any advantage to undercoating ?

And what about oiling the frame ? Will this prevent rusting ?

Wooden plugs that you hammer in. Cork, rubber, whatever.

I would think that whatever you use to try and seal up those tubes will also cause moisture to become trapped inside. So I wouldn’t try to plug them up. I think the best thing is to just try and keep them cleaned out, let the “fresh air” get to them so if they do get dirt or anything in them, it will dry out. In my opinion undercoating is unnecessary. If probably applied, it might prevent future rusting. But with the chance of the inexperienced 18 year old spraying anything and everything he sees, you’re taking a greater change of plugging something that needs to be open, so you’re spending money on something that has the potential to cause future problems. Oiling the frame? I wouldn’t. I don’t see how any type of oil won’t get washed off the first time it rains or you go through a car wash. The car frames, bodies, and panels are dipped and paint applied with pretty good techniques so rusting on a new vehicle is pretty rare until the original paint gets damaged from a crash or other physical damage. Just wash your truck on a regular basis, hand wax twice a year and you won’t have any rusting problems. I’m not so good myself about waxing twice a year, yet I don’t have any rust on my cars 1995, 1996, and 2004 models

Back in the early 1960’s, the Chevy II (I believe this was the car) had “flush and dry” rocker panels. The idea was that the rain water would be forced through the rocker panels and then the air would dry the inside of these panels. I’m wondering if the engineers at Chevrolet used the same principle on the frame tubes on your Sliverado. I don’t think I would plug them for this reason.

You do NOT want to seal them up. Just the opposite…you want it to drain.

My 90 Pathfinder came with these tube step rails. They were sealed at one end…but water and dirt would get in there and collect and in 3 years they rusted out. I bought new ones…but before I did I checked around about how to prevent this from happening again…

First I drilled about 10 1/4" holes on the underside near the rear of the rails…Then I sprayed undercoating into the rails making sure not to plug the holes I just drilled. I sold the truck 6 years later and the rails were in GREAT shape. Just some surface rust.

Can you get to them with a power washer wand? If so, you could spray into the opening with one of the narrower nozzles. That should dislodge anything inside the tubes.

I agree with Benny, you do not want to seal these. They need to be vented.

What I would do is mechanically clean the dirt out as best possible and then spray the inside of the tubes with rubberized undercoating. While some might correctly say that rubberized undercoating is really a sound deadener, I’ve found it very effective as a rust preventative.