Frame behind cab, is this to thin?

[ColdRice]

I'm doing some work to this k1500. The rest of the frame is nice and solid but this one spot concerns me. The middle and top sections on the frame are still thick but the bottom is definitely getting thin. I do plan on covering the frame in fluid film before putting the bed back on.

Will the frame start to fold if I don't address this? I know chevys eventually start to fold here and the bed will touch the cab.

I'm considering buying this repair section.

Middle Frame Section

Fits 88-98 Chevy/GMC. Made from .125" cold rolled steel. Product ships RAW and uncoated. Welding required to install. The Rust Buster Mid-Frame Section helps to replace the mounting locations for your bed and spring mounts on your 88-98 Chevy/GMC.

www.rustbuster.com

Thought? Opinions? Thanks

 

[Hipster]

I didn't know a piece like that was available. If you want to stop the rust you need to get rid of it. Like sandblasted clean then Epoxy primer. Their demo video of grinding the metal "best you can" and sandwiching two bare pieces together js going to breed more rust rapidly. If welding a piece like that on you still need to weld to clean metal and I would want epoxy in between them with pieces cleaned up where they get welded. Hard to tell how thin it is from the photo but even the side looks heavily pitted.

 

[ColdRice]

I didn't know a piece like that was available. If you want to stop the rust you need to get rid of it. Like sandblasted clean then Epoxy primer. Their demo video of grinding the metal "best you can" and sandwiching two bare pieces together js going to breed more rust rapidly. If welding a piece like that on you still need to weld to clean metal and I would want epoxy in between them with pieces cleaned up where they get welded. Hard to tell how thin it is from the photo but even the side looks heavily pitted.

That was my fear actually, it would be difficult to treat the bare metal inside without compromising the welds. Could I cut out a chunk of the lower section without it folding in? And weld in fresh metal?

I hit it hard with a regular hammer as well as a slag hammer, I have yet to go through fortunately. Here is a picture of the outside.

I'm waiting for a replacment rear crossmember, once that's back on I'm removing the tank crossmember to get better access to this area.

Also I just realized that welded cab/bed mount has to come off to use that repair section, not something I would be confident doing.

 

[alpinecrick]

I didn't know somebody made a peice like that either.

In your case as thin as your rusted frame is those peices wouldn't be a bad idea....

 

[Hipster]

If you're going to section a piece in, the truck needs to be on jackstands some kind of level. I would tack in multiple places, a piece of heavy gauge angle iron or 2x3 box tube to the top side to prevent stuff from moving before I cut. It needs to be clean, I can't stress that enough, and 3/16 needs more heat/amps then a 110v unit can do to be welded properly. I would probably fashion a reinforcement plate/fishplate as well inside the rail.

 

[Hipster]

this is what you don't want to do, support the truck through it's mid-section.


www.gmt400.com/threads/bent-frame-after-cnotch.62004/

 

[ColdRice]

Damn that's pretty rough. Getting that straight again would not be easy

That's a good idea. Anything to keep it from moving. I would definitely do that. 110v mig even with gas wouldn't be enough? Unfortunately that's what I have. I might have to pay a shop if that's the case

 

[Hipster]

Damn that's pretty rough. Getting that straight again would not be easy

That's a good idea. Anything to keep it from moving. I would definitely do that. 110v mig even with gas wouldn't be enough? Unfortunately that's what I have. I might have to pay a shop if that's the case

A Miller 140 amp machine might get it done but your right there at it's upper limits maxxed out. I wouldn't attempt this with a 90/100 amp machine. Clean metal and rust inclusions/contamination in your weld will make a difference. You can have a perfectly good looking weld that's doing nothing more than sitting on top of the metal. An improper repair or improper welding here is a train wreck waiting to happen. 70mph, hit a pothole and it comes undone.......

If 110v machine was all I had and felt confident it was enough to weld it, I'd be more inclined to do the slip over piece.
Rent-all places will rent a welder and some welder co's are mobile. fixture, make the pieces, set-up/prep, and make a phone call.

 

[Erik the Awful]

I do janky stuff sometimes, but I wouldn't trust a 110v welder for that job. Ask around and I'll bet you have a buddy with a 220v mig.

I'd also use a hole saw to make a few more holes to fill in and weld that piece to the underlying piece.

 

[ColdRice]

I like that idea, do the prep work myself and get it to the point of welding. Ask around or hire someone to do that part.

My only other concern is how is that cab mount/bed mount going to fir after adding 3/16" of steel. I assume it's enough for the bolts to not line up correctly. They didn't cover that in the video.

I appreciate all the input glad I didn't tackle this myself