Rocker Replacement

[C.I.Blazer]

Now that winter is here, I am ready to dive into some rust repair. New to all this so let me start by saying how much I appreciate the wealth of knowledge on this forum. I have done a lot of reading (especially lks_dcvn's Bullet thread) and know I will have questions as I go along. Thanks in advance.

So far I have all the body mounts replaced, the top bolted down tight, the cracked door hinge fixed, and the door gaps aligned as well as I could. So today I decided it was time to dive in on the driver's side.

Here is what I started with.

[C.I.Blazer]

Here is what it looks like after cutting some metal away to get a feel for what is going on. I know I will have to cut more, but at this point I am just trying to understand how this all goes together. I need to determine what patch panels I need and get them here before cutting more.

[C.I.Blazer]

Here are a couple of pics from the rear of the torsion box.

Also, the last pic is the outside of the torsion box where you can see a couple of rust holes. The boxes were full of dirt and rust scale. Clearly they have been subject to a lot of corrosion but they feel solid everywhere except these small holes. I was thinking about treating them with a rust treatment and keeping them.

Would this be crazy? Saving a few hundred dollars would be nice, but more than that I feel like keeping them would help me make sure I get everything lined up and put back together correctly.

Or, will I just regret not doing the whole thing down the road? This is definitely a driver not a restoration. Any advice?

[C.I.Blazer]

My first question is about what parts I need. Clearly, inner and outer rocker as well as the front and rear floor support braces (not the slip on ones). Maybe a new rocker box and box end cap if I decide to replace those. Also a rocker box reinforcement plate (wow those are spendy!).

Not clear what parts I need at the A-Pillar and B-Pillar. Is it just the front door pillar? Seems like there is another part here.

How about the back. The rear door pillar. Do I also need the rear cab floor support?

Using GMCPauls site to spec out the parts.

https://gmcpauls.com/Patch_Panels.htm

What else am I missing? Thanks for the help. Can provide additional pics if that helps.

[lks dcvn]

Good stuff!

Answering your -'What patch panels' question - using JEG's website as they have Key Parts and you can sometimes save on shipping.

Note - there is no 'rear floor support' for the rear section of the blazer - it is the triangle piece and the support brace noted below. 1967-72 trucks have rear cab supports that I think you are referencing.

A-pillar - Driver

• lower patch - link - $17.49
• kick panel - link - $24.99
• Front Floor Support - link - $16.49
• Outer Floor Extenstion + Inner Rocker - link - $74.99
• If needed - front floor - link - $51.99

A-pillar - Passenger

• lower patch - link - $23.99
• Kick Panel - link - $24.99
• Front Floor Support - link - $16.49
• Outer Floor Extension + Inner Rocker - link - $74.99
• if needed front floor - link - $51.99

Outer Rocker - both sides needed - link and link - $24 each
B-Pillar Support Plate - need - link and link - $114.95 each + $20 flat rate shipping
Triangle Support Plate (inside b-pillar) - need - link and link - $32 each + free ($20) combined shipping from Classic Parts if you get the reinforcement panels there as well
Torsion/Rocker Boxes - if needed - link and link - ~$150 each
Torsion/Rocker Box End Caps - if needed - link and link - ~$60 each

Bedside patch - between B-pillar and rear wheel - link and link - ~$60 each

I'm a few weeks behind you as I plan to tear into another Blazer and fix similar rust as you in the near future. Take plenty of pix and measurements now to save you a headache later.

Also - keep your original rocker boxes on (if they are pretty solid) and replace them last (if you go that route) - they will hold the integrity of the parts you are replacing now. You can always clean out the originals - paint/coat them and fix the rust if they are in good shape. I did that on a prior project w/o issues.

Another Edit - start watching vids on YouTube so you can see rocker install and tips for what to expect. I've been watching a few lately:

Rocker install (Brothers) - here - note tip on measuring up from the fender mount hole at bottom of A-pillar - good tip
Rocker Floor Fix (Eastwood) - part 1 - part 2 - part 3
Rocker/Floor - (Paulk_C10) - link - link - link - link - link - link
Floor/Rocker Fix (Busted Classic Garage) - link

[best view]

Thank u for doing this it will be very helpful for a lot of people plus jegs does have the free shipping it is the way to go

[C.I.Blazer]

Wow! Thank you so much for the incredibly detailed response. That is going to be a great help to me and I hope many others as well. Great tip on Jegs. Their prices are a little more expensive then what I have been seeing, but when factoring in the free shipping I think it is a net savings.

I watched a couple of this videos in the past but will revisit them now that I am diving in. Since they are primarily for trucks I wasn't sure how the rocker boxes would change the project. Interesting tip on doing them last. I assumed they would be the first to be done.

Any regrets on keeping your existing rockers on your Bullet project? That is still the way I am leaning.

[lks dcvn]

The front floor / supports / lower a-pillar / outer floor / inner rocker / outer rocker is the same between traditional trucks and Blazers/Jimmys. Once that stuff is repaired - the torsion box covers the floor, adds integrity when the top is off and ties together the A and B pillars (limiting body flex).

The B-pillar is quite different on the lower door jam - where 6 pieces come together (hold moisture/debris and then rust).

• cab floor
• bedside
• bedside/rocker support bracing
• triangle floor support brace
• torsion box
• torsion box end cap

No regrets here on keeping the torsion boxes on that project - if they are fully/mostly intact - I would clean them, repair anything needed and then coat them. Other than the top - the best reference point to getting the truck back together as the factory did - is the torsion box. I remove them last and then replace them last as it allows me final access to the bottom of the floor/supports, etc. to assure solid welds and then coat/paint to prevent future rust.

If there is any structural rust in the torsion boxes - and clearly that is opinion based - I would opt to replace them with solid metal. I opted to keep one OEM side on the Bullet project and replace the other - due to thin metal knowing it wouldn't be strong enough to hold if the body were to flex.

Pulled a few pix from the Bullet thread

Pass side torsion box - solid, minor pitting, surface rusted, no holes other than factory drainage one. Cleaned/Killed rust, coated and kept installed.

Driver side - several weak spots in key areas, could easily push/pull metal with my hand. Removed and replaced with new.

If you don't need to replace something - don't feel the need to - solid and surface rust is still a viable part.

[C.I.Blazer]

Those pics really help! After further investigation I think I will keep both rocker boxes. Each one maybe has a small 2x2 area that needs to be replaced but are otherwise solid.

Parts are all ordered and should be arriving this weekend. I have been slowly cutting away more to get an idea of how everything goes together, but don't want to go too far until I have the patch panels in hand.

I do think I need to add a drivers side floor as it has a few weak spots and I need to cut away quite a bit to replace the mostly rusted front floor support. The passenger side is pretty solid but not sure about the floor support on that side.

Will post more pics as I get further into it. Thanks again for help.

[ngnaz]

Great thread and very helpful. Also may need the step down repair panels. Mine looks almost identical.

[jaros44sr]

Don't get hasty and rip both sides apart, finish one side before you move over, check your door gaps often

I just started to work on my doors, repro, much easier to hang if they are empty, mine hang from the rafters, with a couple of rachet straps, next time I take them off I'll put studs in them, to ease alignment and mounting

For me, the most difficult part was the 'B' post, there are about 5 pieces that intersect at that location, plus I added a brace

[C.I.Blazer]

Agreed, trying to focus on the driver's side to be able to leave the passenger side as a reference. Been spending a lot of time just lust cutting rust away slowly to see what I have to work with. Have some A-pillar questions before I even get to the B-pillar. Since so much is rusted away, I am not sure how exactly things are supposed to go back together.

For the A-pillar I start with the front cab support and the inner rocker. Cut the original back to clean metal, cut the patch panels to fit, then butt weld all the seams. The kick panel is next. Butt weld the top where I cut it to fit the original metal. The flanged area on the bottom sits on top of the inner rocker with maybe some spot welds to tie them together? Next is the A-Pillar lower path that gets scabbed in to replace the original and finally the outer rocker covers everything.

My question is regarding the four bolts. Do the top two bolts go through the flange on the cab mount support then through the inner rocker, then through the A-pillar? These get inserted from inside the rocker box with the bolt on the outside? Can you get them in and tighten them with the rocker box in place?

Couple of pics of general mock up.

[C.I.Blazer]

Also, this is just a support piece that gets bolted in with the front two bolts and maybe a spot weld to tie it to the a-pillar patch?

[jaros44sr]

Originally Posted by C.I.Blazer

Agreed, trying to focus on the driver's side to be able to leave the passenger side as a reference. Been spending a lot of time just lust cutting rust away slowly to see what I have to work with. Have some A-pillar questions before I even get to the B-pillar. Since so much is rusted away, I am not sure how exactly things are supposed to go back together.

For the A-pillar I start with the front cab support and the inner rocker. Cut the original back to clean metal, cut the patch panels to fit, then butt weld all the seams. The kick panel is next. Butt weld the top where I cut it to fit the original metal. The flanged area on the bottom sits on top of the inner rocker with maybe some spot welds to tie them together? Next is the A-Pillar lower path that gets scabbed in to replace the original and finally the outer rocker covers everything.

My question is regarding the four bolts. Do the top two bolts go through the flange on the cab mount support then through the inner rocker, then through the A-pillar? These get inserted from inside the rocker box with the bolt on the outside? Can you get them in and tighten them with the rocker box in place?

Couple of pics of general mock up.

Seems to me, you have the proper order of assembly right, the factory put the bolts in from the inside, with nuts in the rocker , but I found it easier to put the nuts at the cab support. And yes that piece you have shown is for the fender support.

Hopefully,, you don't have to cut to far up on the a panel, try and stay away from the bolt plate for the door hinge, in pic 7, it looks like you have enough room to graft in the patch panel

Just tack in the panels, and check the door for fitment, that way if its wrong, you don't have a lot of welds to cut to fix the problem

Do not use brake clean on anything you plan to weld, or you won't be posting any updates

I'm working on the second stage of rosker replacement

16072607256691656036581057526948 by 16072610621553555447164691079643 by [url=https://www.flickr.com/photos/97391199@N06

[lks dcvn]

Yes - you have the correct order of install.

I always start with the cab support as that should provide a pretty solid starting point.

From there - I mock up the outer floor, kick panel and a-pillar to see how alignment looks. I weld the corresponding nuts to the back of the cab support to allow me to pull the metal for the floor, kick, and a-pillar together.

[lks dcvn]

once you have the support dialed in - you can continue working outward.

Note - I had to check where the OEM flanges landed on the driver side before I installed them on the passenger side. The flanges on the cab support (that face outward and where the bolts go through) lay outward of the torsion box metal - I included a pix to show this on my truck

outer floor
kick panel
a-pillar
outer rocker

the fender support ties into the back of the a-pillar and is spot welded on.

[Rustbuster]

I replaced the floor supports and rocker panels on my 67 C10. Before you get too far into welding everything up you should watch Fitzee's Fabrications videos on You Tube. He has several videos showing how to cut and butt weld patch panels, and how to fit panels together. It would have saved me a ton of time if I had watched his videos first.

[lks dcvn]

I had to buy a new set of a-pillar fender supports as my were weak in several areas after I removed them from the old metal.

I use weld through primer when I sandwich metal together to prevent rusting between them after I weld.

I bolt together the lower a-pillar and the fender support and then weld them in. Welds have not been dressed yet in the pic.

[caseyfromMO]

Originally Posted by lks dcvn

I had to buy a new set of a-pillar fender supports as my were weak in several areas after I removed them from the old metal.

I use weld through primer when I sandwich metal together to prevent rusting between them after I weld.

I bolt together the lower a-pillar and the fender support and then weld them in. Welds have not been dressed yet in the pic.

I have seen several pictures where the fender support piece is actually behind the cab support. Still welded on the A Pillar but its behind that. Can you confirm what the proper placement is?

[Toro]

This is such an informative thread. I do have a question.

How did you line everything up for the bolt holes at bottom of a-pillar? I was surprised to see that unlike the factory pieces, there aren't any holes on the flanges of the floor support or on the a-pillar patch.

[Rustbuster]

I always make a reference mark on the front and rear door pillars, and measure to the center of the holes, and to the bottom of the inner and outer rocker panels before I cut out any rust. Refer back to these measurements when you tack the new parts in place and test fit your door before welding everything up.
I also traced the holes on a piece of thin cardboard so they would have the same spacing as the factory. You can also find the measurements in a 1967-72 Chevy truck assembly manual.