6? K10

[DavidR]

I have a question about rebuilding an old Chevy truck. A couple of years ago a young girl ran a stop sign on the highway in front of me and my 71 K10 was totaled (frame bent/cab pillars bowed out/steering locked). I kept the truck as part of the insurance settlement. I just looked at a mid 60's K10 (think it is a 65 or 66) but missing the engine. Owner said it had a straight 6 in it previously. It shouldn't be to bad to move the 350 from the 71 to the older truck. The thing I am not sure about is just swapping the engine or swapping the entire drivetrain over? From what I remember, the old 420 transmission and the Rockwell transfer cases were pretty rough. How much trouble would the swap be? A plus is that I would have the power steering pump and gear, brake booster, and whatever else I could salvage from the 71 to use on the other truck. Thanks for your help.

[Rickysnickers]

Welcome to the forum. I'm going to move your thread to the appropriate area. The guys and gals there will probably have more answers for you.

[Short 3/4]

Originally Posted by DavidR

I have a question about rebuilding an old Chevy truck. A couple of years ago a young girl ran a stop sign on the highway in front of me and my 71 K10 was totaled (frame bent/cab pillars bowed out/steering locked). I kept the truck as part of the insurance settlement. I just looked at a mid 60's K10 (think it is a 65 or 66) but missing the engine. Owner said it had a straight 6 in it previously. It shouldn't be to bad to move the 350 from the 71 to the older truck. The thing I am not sure about is just swapping the engine or swapping the entire drivetrain over? From what I remember, the old 420 transmission and the Rockwell transfer cases were pretty rough. How much trouble would the swap be? A plus is that I would have the power steering pump and gear, brake booster, and whatever else I could salvage from the 71 to use on the other truck. Thanks for your help.

To be honest, there were a lot of major changes to the 4x4 trucks between 66 and 67. Since you already have all the (known good) running gear I would look for a good 67-72 body. Should be easy to find a nice one from a 2wd for a reasonable price and it will basically just bolt on. Parts have always been harder to come by for 66 and older (bad for guys like me, but good for you)
If your dream is to have a 60-66 body on your running gear, you should find a 2wd and graft the body on your frame, but be aware there will still be fiddly fab work and it will never be as “right”. Also you will not be messing with a fairly rare 60-66 factory 4x4 that someone could just drop an engine in and go.
Good luck with whatever you decide
Tom

[cwcarpenter98]

If the truck you looked at had a 250 inline 6, then your 350 will bolt up just fine to the sm420. If it had a 292 inline 6, you'll have to change out the passenger side frame stand that sat further forward on the frame.

I haven't messed with the 4wd trucks, but if you take the transmission and transfer case mounts from your 71, my guess is it would probably be fairly easy to swap out the entire drivetrain

[Short 3/4]

Oops,
Sorry, just reread your post and noticed the frame is bent. That changes things.
While putting your old engine in will be a slam dunk, swapping out all the rest of the running gear will take some fab work, and again, it will never be as “right”, but that’s a personal decision.

As far as the transmission goes I have driven many of both types and would personally take a 420 over a 465 any day, but I know others will argue that point.

If the 221 is in good shape I would just leave it. Bearings and gaskets are not that big a deal if needed and the divorced setup is easier to work on because you don’t have to drop the transmission. If the gears are toast then parts can be difficult. It also runs louder. Driveline angles are better though, because the outputs are lower, that’s why earlier trucks ride higher. Unless you’re out doing stupid stuff either case with last just fine

Hope this helps

[Short 3/4]

Originally Posted by cwcarpenter98

If the truck you looked at had a 250 inline 6, then your 350 will bolt up just fine to the sm420. If it had a 292 inline 6, you'll have to change out the passenger side frame stand that sat further forward on the frame.

I haven't messed with the 4wd trucks, but if you take the transmission and transfer case mounts from your 71, my guess is it would probably be fairly easy to swap out the entire drivetrain

CWC is absolutely correct about the engine bolting right in IF the motor mounts are directly across from each other. If the pass side is forward, then it’s a 292 mount and nothing else will work. You will have to find the right one, as you can’t just move it back.

As far as the trans/transfer mounts go they are very different. Take a good look at both side by side and you will see it’s definitely not a bolt in. You will have to evaluate your fabrication skills.

[Short 3/4]

Originally Posted by Short 3/4

CWC is absolutely correct about the engine bolting right in IF the motor mounts are directly across from each other. If the pass side is forward, then it’s a 292 mount and nothing else will work. You will have to find the right one, as you can’t just move it back.

As far as the trans/transfer mounts go they are very different. Take a good look at both side by side and you will see it’s definitely not a bolt in. You will have to evaluate your fabrication skills.

Sorry, was answering his first post while he added a second which is why my answer didn’t make sense

[mr48chev]

The rear motor mount under the bellhousing are the same from 63 to 72. You shouldn't have to change that crossmember if you swap engine bellhousing, trans and transfer. You will have to change the crossmember under the transfer case. The bolt holes may or may not be in the right place.

The OD on the bearing retainer for the 465 should be a bit larger than the bearing retainer for the 420. That is the main difference in cast iron V8 bellhousings.

In truth if you have all the V8 pieces sorted out and ready to use, and have done the homework on front engine mounts you should be able to roll the truck in the garage, pull the six, stab the V8 and pretty well have it ready to drive away by the end the day. Prep and planning ahead of time helps a lot though.