1964 GMC Palomino Tan Survivor

[caseyjones]

I figured I’d kick off this thread at the beginning. Picked up this truck last night and am still feeling pretty good about it. I have an appointment with the DMV in August so it’ll be mostly planning and doing the bare minimum to drive it down there for the VIN inspection until then. The V6 is running so that’s a promising start! Hoping to follow the same formula as my C10, and see which truck I end up liking better 😁

[Low Elco]

Can't wait to see what happens!

[caseyjones]

Plans for the truck are similar to what I've done on my C10. I want to keep as much original character as I can but also make it reliable, easy on the highway and low. I'm going to convert to 5 lug, or I could live with 6 lug if the right deal on a rear end came along. I have another NP440 in my attic, but I'd have to find or modify a shifter to work with it. The electrical system will need some attention. The body isn't too bad, the rust will be one of the last things I'll tackle.

I'm coming across some decision points on suspension. I'm shooting for the same 4.5"/6" drop that I've got on my C10.

1) this is a leaf spring truck. I measured 52" eye to eye on the springs...is this how the squarebody trucks are set up too? Seems like a set of 1/2ton springs and a flip kit would be a no-brainer.

2) I love the ride of my C10. I could swap to a trailing arm setup instead. Probably more expensive...convince me why I should.

3) CPP makes conversion spindles that use the stock 3/4 ton lower a-arms, but I want to rebuild the whole suspension and the MOOG balljoints are $$$ and the inner tie rod joints are unobtanium. If I swap arms, i'd prefer to grab the early lower arms and steering linkage so I can use CPP's drop spindle that doesn't change track width. I can find squarebody trucks in the pickn'pull any day but I don't like the track width change that comes with using those arms and spindles. Seems like no great solution here.

4) I want to try manual brakes on this one with the stock squarebody discs. What MC bore size works for that combo?

[Low Elco]

Don't know the spring lengths- I can measure my 87 tomorrow.

Trailing arms and coils are a FAR better ride. Converted our 67 to coils with a No Limit long travel kit and it's SO much better, and really hooks a corner.

From my experience the arms are the same, size wise. Find a square and get the PS box and crosslink ('82 and up are different). Some spindles push out less than others. There are some charts kicking around for all this, lolife99 has a good one.

Don't know about the MC- Rokauto I have found to be a good tool for digging that kinda stuff up. I'd do the 3/4 ton caliper upgrade.

this ought keep ya occupied- https://67-72chevytrucks.com/vboard/...d.php?t=647790

[88Stanger]

Awesome! I will help if i can with any extra parts i may have that you need.

[lunatic1968]

I love GMC trucks, good find !

[caseyjones]

Originally Posted by Low Elco

Trailing arms and coils are a FAR better ride. Converted our 67 to coils with a No Limit long travel kit and it's SO much better, and really hooks a corner.

I’m leaning pretty far toward converting to trailing arms…anybody out there know if the rear crossmember that carries the shock mounts and upper spring reinforcements from a c10 will fit a c20?

[cwcarpenter98]

That looks like a real nice survivor.

Looking at a picture of my 65 C20 frame, the rear crossmember sure does look similar to the one on my 63

[caseyjones]

Doh, just realized I could measure off my own C10! Certainly looks the same.

[lobuck64]

Hey I used rear axle out of a 76 c10 with original leaf springs and flip kit that included u-bolts for 73-87 c10 also have to reuse axle shock mounts from original axle hope this helps pm me I can send photos of my swap

[caseyjones]

Originally Posted by lobuck64

Hey I used rear axle out of a 76 c10 with original leaf springs and flip kit that included u-bolts for 73-87 c10 also have to reuse axle shock mounts from original axle hope this helps pm me I can send photos of my swap

Thanks for the info Lobuck. I have decided to convert it to trailing arms though. I happened to be near user MT65 last week while on vacation and picked up the complete rear from his 65 and a set of mystery front springs. The rented minivan had no trouble with it

It's a start. Now I'll need to find the rest of the rear suspension parts to mount it!

Current challenge is to rebuild the front brakes enough to move it in and out of the driveway and get it down to the DMV. thankfully the front brake parts are pretty inexpensive.

On the way back we came across an awesome collection of old trucks and automotive oddities in Pomeroy, WA. This GMC still looks like a workhorse...

[caseyjones]

Brakes work. Truck moves forward and backward. Good enough to get to the DMV in 6 weeks.

In other news I snagged a horn button from eBay for a good price. The speedometer is the only other GMC-specific item I need to replace.

[caseyjones]

I’m rethinking using the conversion spindles…my concern is the inner tie rod ends. LMC has them in their catalog for <$20, and NAPA has them for $150. Anybody have first hand experience with the LMC c20 inners?

[caseyjones]

Parts are starting to pile up...rear wheels, front tires, drop spindles, brakes, axle, trailing arm suspension, springs, etc etc...

Found a seat from a 67 down in Newberg. Needs a new cover but the springs and foam are good. Kinda like the green and tan combo...

Tried straightening out the bed side...i think I'm gonna have to grind out all the bondo and try again.

I have cleaned up the wiring and it's impressively intact and functional. Fuel pump started leaking from the weep holes, so that got replaced and the oil was changed. Took it for a lap around the neighborhood and it was terrifying. Brakes are super sketchy and the carb is probably junk. But it was still fun!

DMV appointment is next week, then the fun begins!

[caseyjones]

The DMV appointment was successful, I have plates and a title on the way. The drive to the DMV highlighted a weakness in the radiator, so I need to pull it out and get it repaired. But other fun stuff is happening.

I started stripping down the truck and mocked up the front brake setup. I'll be welding tabs to the upper a-arms to mount the squarebody brake hoses. I had to bend the hose end at the caliper a little bit to clear the upper part of the spindle, apparently a common thing to do on the square trucks. I bent a line that goes forward to the crossmember under the radiator, across and to the other side. A 40" pre-flared line worked perfectly for that. i'll also be replacing the ball joints and outer tie rod ends.


I also started with the new brake system. I installed a 1" bore dual master cylinder that I had on my green truck. I found out it was too sensitive for the power brakes on that truck so I thought it might be perfect for the manual brake setup I want to try on this one. The master cylinder bolted right up, doesn't look like I'll have to mess with the pushrod or anything. I'm waiting on a t-fitting before I finish running the front line up to the master.


Also started pulling the rear end apart-driveshaft is out, parking brake and shocks disconnected. I will be pulling the bed off next in order to get the upper shock mounts and leaf spring mounts out and to install the coil-spring shock crossmember. Not really much to see there.

Last, I installed the Holley so I can figure out fuel line fittings/routing. I don't love the polished finish but it was the most affordable version, so i'll live with it.


I'm kind of hopping around, doing stuff that I have parts for while I wait on other parts to show up. I have wheels at the sandblaster, balljoints in the mail, a bunch of fasteners on order with Fastenal, etc. Should start coming together soon though.

[caseyjones]

Went camping this weekend so only had a few hours tonight to make progress.

Turned the driveway into a mess - took off the bed and got the 3/4 ton rear end out of the way. I love my wife


Started cleaning up the remains of the rear half. Cut out the exhaust right at the center crossmember - it was pretty rotten and pretty obvious that it wasn't going to work with the trailing arms.

[Low Elco]

Progress! Coming along!

[caseyjones]

Originally Posted by Low Elco

Progress! Coming along!

I was making more progress last night till a wrench slipped and I ended up waiting 4 hours for some stitches. Wear gloves, dummy! Anyway, I have all the unnecessary brackets knocked off the frame and I have the trailing arm brackets bolted in. No more dirty work for a little bit while this heals up.

[The Rocknrod]

Heck I bled on mine a time or two during the build.
Great progress and thanks for the heads up.

[caseyjones]

This truck wants to mangle my hands. Smashed a finger while replacing balljoints, too. But I'm pretty much healed up now.

Got everything put together on the rear end. Just lots of grinding out rivets and replacing with 3/8" grade 8 bolts. I started with 5" drop springs and 2" blocks.

Front end has new ball joints and outer tie rod ends. CPP modular drop conversion spindles, and standard squarebody brakes. Going with a manual brake setup, 1" bore master cylinder...we'll see how it does on the street. I ended up with a pair of mystery front springs...might be 1.5" drop cheapies from ebay.

I used a CPP intermediate shaft assembly...ended up making a frankenstein rag joint from my old one, since the new one had a flat and my steering box is fully splined. Ground the DD using somebody's method on here with a block of wood as a guide...worked awesome!


And this is what it looks like in the driveway, before and after:


It's low...probably equivalent to a 5.5/7 drop. I have the c-notch, so I have to decide if I want to leave it here...

Radiator is getting repaired now. When that comes back I can start putting some miles on it and see what else is broken!

And I'm also thinking about a big back window conversion...

[cwcarpenter98]

Oh yeah, that's a good look

[Low Elco]

OOOOOh! So Much better!

[caseyjones]

Thanks guys. Some learnings about the front end spindle swap that might help someone else: This truck started as a 1964 GMC 1500 (3/4t). In 1964, the 3/4t trucks had lower a-arms that bolted to the crossmember, not the u-bolt style mount. That rules out a simple swap to 1/2t lower arms. The alternative was to swap to a newer 1/2t suspension, but I figured it would still need to be completely rebuilt plus I’d have to go through the extra expense and effort of installing the core suspension.
Also, CPP still lists two styles of conversion drop spindles but only the modular style is still available.

[88Stanger]

Love the look! great job so far....

[caseyjones]

Just got the quote to re-core the radiator…$650!!! I will be ordering an aluminum unit from Champion tonight.