1971 K10 Stepside - Getting a Roller Roadworthy

[pjmoreland]

I've been looking for a 115" wheelbase K10 at a reasonable price and in need of rehabilitation for a while now. I bought this one locally from a woman who owns a body shop. It appears to me that she and her husband were buying and restoring classic trucks as part of their business. Sadly, her husband, who was young, passed away recently, so she is selling off some vehicles. I hauled it home a few days ago.

The truck is stripped down pretty far. It has no engine, transmission, transfer case or driveshafts. The body, however, appears to have no rust holes anywhere, and that's the main reason I decided to go for it. A Chevy Truck Red Book I've got says there were 1438 of these short wheelbase stepside K10s build in 1971, so it's definitely worth keeping.

My initial plan is to focus just on getting it roadworthy. I'm also going to undo the crazy high lift it's got right now. It's got a 4" body lift, and the leaf brackets have been welded to the frame with sections of box tubing between them and the frame. I will be grinding all of that off so that the brackets can be reinstalled in their original locations.

My plan is to find an NV4500 transmission and an NP205 transfer case. I've got a used l31 Vortec 350 that's in decent condition that I'm going to throw in it. The one bummer is that I'll have to install an electric fuel pump since the l31 block isn't machined for a mechanical pump.

It's going to be a bit slow going at first because I have some other projects I need to finish up. The transmission is removed from my '68 stepside right now, and I'm going to be rebuilding the 4L60 transmission in my '89 over the next couple of weeks.

I ordered a windshield yesterday so that I can get the cab sealed up before the rain comes.

[pjmoreland]

It hasn't been on the road since 2001. The VIN tag, the partial VIN on the frame, the VIN on the SPID and the VIN on the door sticker all match, which will be nice when it comes time to get a VIN verification at the DMV.

[pjmoreland]

Air brakes

[68bowtie]

I like the truck, and good plan.

[pjmoreland]

Originally Posted by 68bowtie

I like the truck, and good plan.

Thanks. I'm on the fence about going with an NV4500. An SM465 with big tires and 3.73 gears would probably be just fine on the freeway.

[jerry moss]

Pat,
my old 69 K10 that i restored back in 95 had a 350, 465, 205 combination with 3:07 gears with 35 inch tires and on flat ground it got 18+ mpg, in the mountains i seldom used 4th gear pulling hills but off road in 4low first gear it would crawl fine.
looks like a solid project and a good plan you have.

[pjmoreland]

Originally Posted by jerry moss

Pat,
my old 69 K10 that i restored back in 95 had a 350, 465, 205 combination with 3:07 gears with 35 inch tires and on flat ground it got 18+ mpg, in the mountains i seldom used 4th gear pulling hills but off road in 4low first gear it would crawl fine.
looks like a solid project and a good plan you have.

That's impressive gas mileage. I'd be ecstatic if I got even close to that.

[NGN]

Cool truck, I'm a more of a 67-8 we'll more 67, don't get me wrong I would have all 67- 72 if possible, not one I don't like. 69 and 70 4x4 to me, look the strongest, had a meaner tougher look, well that's me. Nice project you got there it Especially looks killer next to your 98. Caught my attention, had me curious for a spilt second, air brake LOL 🤣🤣.
NGN
Nick

[pjmoreland]

Originally Posted by NGN

Cool truck, I'm a more of a 67-8 we'll more 67, don't get me wrong I would have all 67- 72 if possible, not one I don't like. 69 and 70 4x4 to me, look the strongest, had a meaner tougher look, well that's me. Nice project you got there it Especially looks killer next to your 98. Caught my attention, had me curious for a spilt second, air brake LOL 🤣🤣.
NGN
Nick

I prefer the 67/68 trucks as well. My first truck was a 67 C/10 stepside that I drove every day for 12 years. Second choice for me is the 71/72 grille. I like the bowtie in the center of the grille instead of on the hood. The one downside in my opinion is the use of plastic for the inner grille. For 69/70 at least the majority of the grille is metal. Isn't it funny how much better the 67-72 trucks look compared to the newer stuff??

[57taskforce]

Nice find! For what it’s worth my K20 has a 5” lift with 4:11’s, 35’s, with a 465 and it runs 65 mph at around 2500. With the assumed numerically lower half ton gears you’ll be even better than that. The shift spacing/RPM drops can kinda suck on the 465 with bigger tires, but with that L31 you should have the torque to do what’s needed. That looks like an excellent start to me. Get rid of the cobbled together crap on the hangers and you’ll be in business. Make sure and check around the steering box for cracks in the frame and also the front crossmember and engine cross member for loose rivets or bolts. The 4x4 trucks are pretty notorious for this. I’d add an ORD steering box brace that ties that area of the frame to the front crossmember, which triangulates the whole area. If the frame is cracked, several places sell the plates to fix it. The swb K10 and blazers have thinner/weaker frames than the lwb K trucks do so they do have the potential to crack more than the lwb K’s. Both my swb K10 and my K20 had cracks in the frame around the steering box.

[pjmoreland]

Originally Posted by 57taskforce

Nice find! For what it’s worth my K20 has a 5” lift with 4:11’s, 35’s, with a 465 and it runs 65 mph at around 2500. With the assumed numerically lower half ton gears you’ll be even better than that. The shift spacing/RPM drops can kinda suck on the 465 with bigger tires, but with that L31 you should have the torque to do what’s needed. That looks like an excellent start to me. Get rid of the cobbled together crap on the hangers and you’ll be in business. Make sure and check around the steering box for cracks in the frame and also the front crossmember and engine cross member for loose rivets or bolts. The 4x4 trucks are pretty notorious for this. I’d add an ORD steering box brace that ties that area of the frame to the front crossmember, which triangulates the whole area. If the frame is cracked, several places sell the plates to fix it. The swb K10 and blazers have thinner/weaker frames than the lwb K trucks do so they do have the potential to crack more than the lwb K’s. Both my swb K10 and my K20 had cracks in the frame around the steering box.

Thank you for the guidance! This is my first K truck. I will inspect the frame once I've removed the hidden shaft-driven winch and can look around in there. I added the ORD brace to my long, long parts list.

[pjmoreland]

Looks like it had had some repairs done to it.

[pjmoreland]

Picked up a windshield yesterday, and received a Precision seal for it. Sprayed the opening black in preparation for install.

[57taskforce]

Yep that definitely has had some work done. You have the factory brace so that is a good thing. Neither of my trucks had it. Some got it some didn’t.
My suggestion… strip it down and be really sure of what you’ve got. If it wasn’t repaired correctly those cracks will continue to spread. This is the repairs I did to my K10 last winter just so you can see what it entails. Mine had been poorly repaired in the past and had several cracks that had still spread after the repairs. I drilled both ends of every crack I found and then “V” beveled them as deep as I could without cutting thru the rail then filled them back in with the Mig and flap disked almost smooth; I always try to leave the top a little high when I can so as not to thin the metal out too much. Then once that was done I welded the repair plates over top. Be really sure you get every one. They can be hard to see at times. Mine got ran for a long time with no front crossmember so it was really bad compared to my K20 because of the extra flex and movement in the frame rails.

Note the washer welded to the top of the frame where the front crossmember is now bolted. I did this on all the holes for the front crossmember and the engine crossmember. The holes in the washer a drilled ever so slightly undersize of 7/16 so I could ensure a tight fit in with every thing and do my best to eliminate all chances of movement in the frame.

[pjmoreland]

Thanks! I will pull off the steering box and give it a thorough inspection.

[57taskforce]

These two cracks actually opened up with a loud “pop” as I was welding another on the side of the rail in an area near by. I ended up wire wheeling the rail to bare metal nearly a foot on both sides of the repair area as much as possible to make sure I got them all. This is the bottom view of the crack circled in black above.

[pjmoreland]

Dang. Hopefully any cracks in my frame will be visible from the steering box side. It would be a real challenge to remove the plate someone welded to the inside.

[pjmoreland]

I can see one crack directly forward if the steering box.

[57taskforce]

I’d bet it probably goes from one of the steering box holes to that bottom rivet. Definitely look all that over really close. I got my plates for my K20 from ORD and for my K10 I got them here. Same identical parts but 1/2 the cost.
https://www.amazon.com/G-PLUS-Suppor.../dp/B09WMBFC1C