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1968 C15

#1
Now that my dad's 64 C10 is done, we've started on my 68 C15. I'm the 4th owner of this truck - it had about 34,000 miles on it when I bought it last September. It's original paint, original 327 and 4-speed. I've been gathering parts over the last few months and excited to finally be starting on it. I'm doing a frame-off restomod on this one. The major changes will be the LS swap and short bed conversion, lowering, add A/C, power steering, power brakes, and relocate the gas tank. With everything we learned on my dad's truck and how similar these trucks are, mine should go a lot faster and easier.

I bought an LQ9 out of a 2004 Escalade with about 110,000 miles on it as well as a rebuilt 4L80E. The engine had a lot of grease, oil, and dirt on it and the block was rusty so I took it apart Saturday to clean and paint it. I pulled a valve cover off and the heads looked good.

bought a needle scaler at Harbor Freight to clean up the block and it worked well. I also sandblasted the block and timing cover in prep for paint. The remainder of the engine was treated with degreaser and scrubbing and looks much better. I also painted the power steering/alternator bracket and tensioner. I didn't have a lot of time Sunday, but was able to get the bed off.

Next weekend I hope to get the engine and trans out so I can sell them and get the front end apart.

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#3
I absolutely love these trucks! Along for the ride on this one. Are you keeping the leafs?
At this point, yes. It would be cool to convert to coils, but it's one of those upgrades that I'll keep on my list for another day. In the meantime, I'll install drop shackles and new shocks and see how it handles. Sway bars are also on my future upgrades list.
 
#4
I'm surprised how different the rear crossmember is when comparing coils to leafs. I've never looked closely at one with rear leafs before I guess.
 
#5
We made a lot of progress Saturday-we pulled the the rest of the body, engine and trans out. Also discovered that the engine is actually a 307, not a 327. Next steps - frame shortening and disassembling front suspension to get the chassis ready for the sandblaster!

My dad and I decided to take a picture with all of our trucks a couple weeks ago as it was the last time for awhile that they will all be complete. My 2016 and 1968 and my dad's 2006, 2003, and 1964. I drove the 2016 in high school and he decided to keep it and his Sonoma has been his daily driver for about 15 years. He was about to sell it as he's now driving his 64 every day, but he had second thoughts and wants to LS swap it after we finish my truck!

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#6
It'll be great to watch the progress of this build! I have to admit I am a little sad to see the original engine go, but it's totally understandable why the LS has just become completely dominant.
 
#7
It'll be great to watch the progress of this build! I have to admit I am a little sad to see the original engine go, but it's totally understandable why the LS has just become completely dominant.
It ran great - I have no complaints there, but the LS makes so much more power while getting better mileage and the aftermarket is huge.
 
#8
Last night I did what I should have done last weekend when I had the intake off - replaced the knock sensors, harness, and intake manifold gaskets on my LS. There was a lot of gunk down in the knock sensor recesses and they were pretty corroded. I also started the frame shortening by cutting off the rear tails of the rails. Hopefully this weekend I can do the rest of the frame shortening.

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#10
Well, you go the easy part of the frame shortened. How are you going to do the rest of it? (Z cut, Brother's plates, etc?)
Yeah, it took me a solid 15 minutes to do those cuts. I plan on doing an angled cut with a fish plate. I think the Brothers kit is overpriced for what it is. From what I've read, as long as you take good measurements prior to cutting and are precise with the marrying of the two frame rails, it's a solid modification. And with the Brothers kit, you end up with a sandwiched layer of steel which I don't like from a rust standpoint. It's $400 and comes with brake cables and brake line, but I can buy those for a lot less than $400 so you end up paying $300 for a template which really isn't mandatory.
 
#11
Oh yeah, as long as you get good penetration on the welds, it will be fine. Personally, I think the fish plate is a little bit of overkill. I assume you are making the cut under the cab, so you don't have to worry with the trailing arms crossmember?
 
#13
Oh yeah, as long as you get good penetration on the welds, it will be fine. Personally, I think the fish plate is a little bit of overkill. I assume you are making the cut under the cab, so you don't have to worry with the trailing arms crossmember?
Yes, my plan is to make the cut under the cab where the frame is straight and bevel the edges before welding and I won't have to mess with the crossmember.
 
#14
Frame shortening is complete. I recycled the cut sections as fish plates on the inside. We cross-checked for square and it was within 1/8" so I'm happy. I also removed the manual trans crossmember, clutch linkage bracket, brake lines, and fuel lines.

Next weekend I should be able to drill for the rear cab mounts, pressure wash the chassis, and finish taking it apart so I can take it to the sandblaster.

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#15
Looks nice! I had forgotten that your truck is a GMC, w/leafs. That crossmember didn't do anything but hold the carrier bearing. Are you going with a 1-piece driveshaft?
 
#17
Finished disassembling the chassis Saturday and dropped off at the sandblaster. There was about a 2" thick buildup of New Mexico sand, grease and oil around the ball joints. It was a workout removing the old cross shaft end caps - had to use a 16" crescent with a 4' cheater to loosen them.

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#18
Nice update! I ended up buying the sockets for those caps because I didn't want to mar the new ones. Haven't used them since lol, but I'm sure we haven't seen our last old GM pickup.
 
#19
The sandblaster is pretty backed up, so I didn't get any parts back last week and I might not this week either. But progress is progress, even if it's not the order I planned on. I was able to spray chassis saver on all of my new chassis parts - steering gear, pitman arm, idler arm, cross shafts, and spindles and I also painted my calipers. The engine and trans are mated together and I have one door emptied.

I'm really hoping my sandblaster can get to some or all of my parts this week, but not crossing my fingers.

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#20
Saturday we got quite a bit done. I decided that I want to mount my PCM and TAC module in the cab, so I laid out my harness, pulled the loom and tape, and rerouted wires so I can have one bundle running down the top of the transmission and I'll bring them up underneath the seats. I'll be spending some time in the evenings lengthening and shortening the wires back to the PCM connectors to clean up the spaghetti mess of wires I have now. I think what I'll have to do is label each wire for its position in the connector and pull them all out in order to sort out this mess.

We also deskinned both doors so I can take them to the sandblaster with the next batch of parts. The cab is also stripped and I'm ready to start closing up holes in the firewall, floor, and a few other spots (spotlight hole in driver's side pillar, gun rack mounting holes).

I ordered a cam swap kit last week so next weekend I will be swapping that out with new valve springs.

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