Def butt weld it,
I do NOT recommend lap welding body panels.
Yes, lap welding is easier with less chance of burn thru because you have more material,
BUT with lap welding the panel, you're creating a joint where moisture and dirt can settle into and start the rust process allll over again.
As said,
Weld thru primer is good insurance and a lot if panels are coming painted with it already, so check if that's the case.
but if not, be certain to clean off any oil or coatings off the patch (it can contaminate your weld) then apply weld thru primer.

 

Moisture and dirt can't get in if it is properly sealed from both sides, like I outlined above.

If all you have is some $200 Harbor Freight flux core wire welder, lap welding may be the only way.

I use inexpensive Transtar 4353, it's under $20 a can.

 

But if it's inside the rocker, how can it be sealed properly?
Particularly if you're just throwing metal on top if metal you can't be certain it's sealed butt welding insures there's no seam or joint for moisture/debris to form in,
I've seen it hundreds of times where a lap welded body panel has started rusting allll over again,
Don't believe me?
Wait a couple years and cut that lapped patch off, you'll be surprised

 

Which is EXACTLY why I would never try and "patch" a rocker.
Especially when I have the whole piece in my hand.

How do you expect to dress and prime the back of a butt weld either?

 

100% agree
Given the differences though a butt weld would last longer, relying solely on weld-thru primer as insurance, which with a patch is the only option unfortunately

 

THIS is just a cab corner for an extended cab truck...
if that is what you are talking about, there is access when you cut it out.

 

Ah I thought he was referring to a rocker not a cab corner, yup that's a cab corner, you are correct.
But when it comes to body panels,
I butt weld, that's just how I work,
better results, longer lasting IMO.
To each their own I suppose...

 

Sorry, double post from my phone.

 

Oh yeah,
Absolutely!
But I don't think it matters much for a cab floor.

 

Yes that is the part, the cab corner I guess is the technical term. I have always referred to the lower part of the exterior body panels as the rockers.

 

Nope at least not with the 92 -97 model years, there is an inner wall blocking access to the back side from the inside of the cab.

If rusty will likely have to fix it too.

Couple of pictures,








Turnkyle,

I do have a full series of pictures if you'd like to see them all, just ask and I'll post them.
Pictures I took while fixing my 95 from rust in the same point. The rust probably extends into the cab further then you'd tend to think based on what is seen from the outside too, I was surprised how much actually had to be cut out and replaced up into the cab wall/floor once got into it, from just showing little bubbling under its paint.

 

Exactly what I mean.

There is access when you cut the inside out. (in my case, the B-pillar)

You need to get all that crap insulating foam out anyway, or you will set the truck on fire welding.

 

I see thought you guys where thinking could get to the backside by simply removing the inside trim panel, yea only way to do it would be to cut the inner wall out and quite a bit of it too!

I did not cut it out I replaced the rust damaged section working from the outside. While I do not drive the truck in the winter I did best I could treating it as if it would be driven in the snow.

I could not access the backside of the weld after the fact but provisions made for that during the process.

Yea that foam it is what makes em rust there to start with and all in the name of making them "quiet" doing so cheap as possible.

 

Danr1,

I would like to see a full series of pics if you have them. I was hoping to not have to replace much on the back side seeing as how from uder the truck every think looks pretty solid still. I was hoping I could get away with just sprayin rust converter and rubberized undercoating in there for sound reduction.

 

Here are a few shots I took during the process, will put them up in more than a single post.

Right or wrong this is how I did it, (I am not a "body man")



Piece shown in the next picture had already been removed when I took this one.
This is just after removing the outer skin the section hanging on by couple spot welds, pretty much came off in my hand.




Piece pretty much wasted no point in trying to fix it so had to construct a new one as shown in next picture.