I saw you had replied and I thought uh-oh. I'm glad you weren't offended by my suburban comment.
CK5
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'89 R3500 Crew Cab 2wd to 4wd conversion & beyond
- Thread starter mrk5
- Start date
Started out with 2wd TBI350 with SM465 to current 4wd with 454, 700r4, NP241
Didn't quite get as much done yesterday as I'd hoped. Finished the crossmember between the front hangers.
The bottom brackets in the photo above are from the factory crossmember and the tie into the bottom bolts of the spring hangers. The frame here is taller than the original location so I made a new cross bar to tie it all together; see first picture. It's 2-1/2" square tube and 1-1/2" angle.
For all of the bolts on the hangers and crossmember I've been using these bolts. https://www.mcmaster.com/91286A244/ I wanted to use fine thread for these and in searching came across this zinc-aluminum coating. You can read the description from the link, but they are supposed to be 5 time more corrosion resistant than zinc chromate coating.
I had hoped to finish mounting the gas tank in place, but only got the bottom supports in. They have adhesive backed rubber on them. https://www.rockauto.com/en/moreinfo.php?pk=10872688&cc=1301252 The straps will run over the top of the tank and one end will bolt to the angle on the crossmember I made. The other end of the straps will need a bracket made.
We did have to bend down the flange that circles the gas tank. It ended up right at the frame and it's a touch wider than width inside the frame rails.
We flipped the springs around with the longer end forward. That turned into a huge time suck! Found the heads of the center pins left behind and corroded into the spring perches.
The axle hadn't shifted; I think that's a testament to proper ubolt torque. I was able to drill into the heads and use a punch and hammer to pop them out. I used a 9/16" bit to clean the holes out and a LOT of rusty dust came out.
The other part of the time suck was getting the center bolt out of the springs. Took a combination of air hammer and large sledge with a punch. The new bolts went in covered with antisieze.
The final wheelbase is 141". That's 21" less than what I measured at the start.
Now everything is in place so I can start working on the bed once I have the gas tank strapped down.
The bottom brackets in the photo above are from the factory crossmember and the tie into the bottom bolts of the spring hangers. The frame here is taller than the original location so I made a new cross bar to tie it all together; see first picture. It's 2-1/2" square tube and 1-1/2" angle.
For all of the bolts on the hangers and crossmember I've been using these bolts. https://www.mcmaster.com/91286A244/ I wanted to use fine thread for these and in searching came across this zinc-aluminum coating. You can read the description from the link, but they are supposed to be 5 time more corrosion resistant than zinc chromate coating.
I had hoped to finish mounting the gas tank in place, but only got the bottom supports in. They have adhesive backed rubber on them. https://www.rockauto.com/en/moreinfo.php?pk=10872688&cc=1301252 The straps will run over the top of the tank and one end will bolt to the angle on the crossmember I made. The other end of the straps will need a bracket made.
We did have to bend down the flange that circles the gas tank. It ended up right at the frame and it's a touch wider than width inside the frame rails.
We flipped the springs around with the longer end forward. That turned into a huge time suck! Found the heads of the center pins left behind and corroded into the spring perches.
The axle hadn't shifted; I think that's a testament to proper ubolt torque. I was able to drill into the heads and use a punch and hammer to pop them out. I used a 9/16" bit to clean the holes out and a LOT of rusty dust came out.
The other part of the time suck was getting the center bolt out of the springs. Took a combination of air hammer and large sledge with a punch. The new bolts went in covered with antisieze.
The final wheelbase is 141". That's 21" less than what I measured at the start.
Now everything is in place so I can start working on the bed once I have the gas tank strapped down.
That looks awesome
Fuel tank is strapped down. Used a scrap piece of 1-1/2"x3/16" angle bolted to angle tab pieces on the frame.
The front of the straps bolts to the crossmember.
The front of the straps bolts to the crossmember.
I added a rear crossmember between the shackle flip brackets.
Also finalized fuel hose routing. It connects to the factory hardline where the tank selector switch was.
The trickiest part was decoding the fuel pump wiring. This is the harness that runs from the drivers side outside of the frame rail, across under the rear of the cab to the tank selector switch on the inside of the passenger frame rail.
Lots of wires. From the tank selector switch there are 2 wires which are power for each pump. Those are spliced in the harness above so that it feeds power to the pump and also the selector valve to move it to the proper position.
I assumed pump power went to the selector valve and then out to the pump.
Then you also have tank level. Each tank is wired back to the selector valve and the valve completes the connection to the wire sending signal back to the gauge. I had assumed the fuel pumps would be wired similarly, but they are not.
The odd thing with the fuel guage wire is that 2 wires come from the front of the truck into a connector but only 1 wire comes out. I left it that way because I don't understand why it's setup like that and I didn't want to mess something up.
I'm only using one of the pump power wires. I tried twisting the 2 together on 1 connector terminal but that didn't work. I assume because power was coming in off 1 wire and just running back on the other side instead of powering the pump. It works fine with 1 wire connected. In the future I can eliminate the selector switch in the cab.
For future searchers, the gray wire off the Suburban TBI sending unit is for pump power. The purple wire is for the fuel level gauge.
Glad shortening the frame will allow me to eliminate this mess from the previous owner; I think it got melty at some point.
Also finalized fuel hose routing. It connects to the factory hardline where the tank selector switch was.
The trickiest part was decoding the fuel pump wiring. This is the harness that runs from the drivers side outside of the frame rail, across under the rear of the cab to the tank selector switch on the inside of the passenger frame rail.
Lots of wires. From the tank selector switch there are 2 wires which are power for each pump. Those are spliced in the harness above so that it feeds power to the pump and also the selector valve to move it to the proper position.
I assumed pump power went to the selector valve and then out to the pump.
Then you also have tank level. Each tank is wired back to the selector valve and the valve completes the connection to the wire sending signal back to the gauge. I had assumed the fuel pumps would be wired similarly, but they are not.
The odd thing with the fuel guage wire is that 2 wires come from the front of the truck into a connector but only 1 wire comes out. I left it that way because I don't understand why it's setup like that and I didn't want to mess something up.
I'm only using one of the pump power wires. I tried twisting the 2 together on 1 connector terminal but that didn't work. I assume because power was coming in off 1 wire and just running back on the other side instead of powering the pump. It works fine with 1 wire connected. In the future I can eliminate the selector switch in the cab.
For future searchers, the gray wire off the Suburban TBI sending unit is for pump power. The purple wire is for the fuel level gauge.
Glad shortening the frame will allow me to eliminate this mess from the previous owner; I think it got melty at some point.
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wow stop my daily CK5 visits for a bit and Dimples gets a total face lift.
I think of it more as a buttock enhancement.....
who the hell uses heat shrink butt connectors and NOT heat them up to shrink and seal ? ? ?
Maybe they figured whatever melted the wires would set the heat shrink... 
I’m with Keith... missed a bunch of your posts and find out you have been busy. Looks great!
Stopped by the shop today and checked out the truck in person, looking good. Can’t wait to see it on the trail.
I can't wait either. I have a July 17th hard deadline.
But still halfway longer than 95% of the other rigs on the trail.
Started welding up bed pieces this weekend. 1 day was spend cutting up nearly 70ft of steel. With steel prices being what they are right now, I picked a bad time to do this project.
These will basically be the fenders.
You can see the adjustable Strong Hands magnet I bought for this. It worked pretty good. At one point it did get out of whack, but otherwise worked well.
Making the tapered ends took the most time. I cut a wedge out of the rectangle tube and bent the side down.
Welding those up should be the most "difficult" part of the fabrication. The rest is all squares and rectangles.
These will basically be the fenders.
You can see the adjustable Strong Hands magnet I bought for this. It worked pretty good. At one point it did get out of whack, but otherwise worked well.
Making the tapered ends took the most time. I cut a wedge out of the rectangle tube and bent the side down.
Welding those up should be the most "difficult" part of the fabrication. The rest is all squares and rectangles.
beags86
Eastbound and Down
Wow, nice work Scott. I haven't been in this thread for a while. So I was also surprised to see such a huge change in direction of the build.
Now you just need AC!
Now you just need AC!
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Thank you. I want to work my way towards an under dash AC unit. I say work towards it because I need to rearrange the dash; primarily the transmission controller needs to be moved. My AC plans for the crew cab got pushed back when I decided to put EFI on the C10.
beags86
Eastbound and Down
Did you ask Dave if that ok first?
I figured using the under dash unit would meet his approval because the factory defroster would still be functional. (I assume that the Dave we're talking about is @6872xtc )
beags86
Eastbound and Down
Dave's not here.. bawahahah
Is there any other dave cruises the trail with the windows up?
Haha, I've noticed the window only seems to go up when I start walking over to talk to him....
