My 1967 Chevy K20 Build Thread

[Chaparralman1974]

Originally Posted by GAc10boy

Awesome work! Really looking forward to following along.

Thanks Robbie! It is definitely a labor of love.


Clay

[72 tigger]

You’re very persistent! Keep it up

[Ol Blue K20]

Coming along nicely, keep up the good work.

[KyleSeal]

Love these old K trucks. Looks great.

[Chaparralman1974]

3/12/2023 - 3/30/2023
Transfer Case Rebuild and Installation of Transmission and Transfer Case Into Chassis
The rebuilding of the transfer case was a little more challenging than I initially thought that it would be. First off, Parts are very difficult to come by, and when they do come along, they are expensive and if they are used, not much better than what you are starting with anyway. I was lucky to find a transfer case out of a 1967 K10 that, as luck would have it, was only 5 minutes away from me. Moreover, I was able to get it for $100, so I totally scored on that one!! I am very lucky to have run across that deal due to the fact that there was a lot of wear in my transfer case. My initial plan was to use the original case that came in my truck and scavenge the other one for parts, but seeing as how the one out of the K10 was much, much better I altered course and opted to use that one instead. This was of course after I put in all the effort to clean, paint, and prep everything in the original case for rebuild. Oh well….I will just rebuild the original case in time and will have it for a spare. Also, the other case came with an adapter for the transfer case, so it is really good to have another one of those seeing as how they were only produced for the 1967 model year.
As stated, parts are terrible to come by. This includes the oil seals in both the transfer case and the adapter. 1967 was the first year of the "married" transmission to transfer case setup in the K10 and K20 series 4x4 pickups. It was also the last year of the SM420. After 1967, the SM465 came into being. That essentially makes the adapter that mates the SM420 to the Rockwell T-221 transfer case kind of a unicorn of sorts. The coupler that connects the output shaft of the transmission to the input shaft of the transfer case is also unique to the 1967 model year. Anyone who has been down this restoration path probably has found that the seals are difficult to come by if not downright impossible. Well, after digging around the inter-webs and YouTube, I have found the seal and it is still in production! It is super hard to come by no doubt, but I wanted to share it all with you in the event you need to source it as well. This is the same seal that is in use in the T-221 transfer case by the way. While there is an alternative seal solution (SKF 17381 being one), it is not of the original opposed double lip design. It is however likely a superior seal due to the higher temperature rating, but the opposed lip seal, IMHO, is better for the adapter due to the need to keep gear lube opposed in both the transmission and the transfer case. At any rate, if anyone is looking for it, I found the seal at Point Spring and Driveshaft Company (https://pointspring.com/). The part number is an Axletech (or Meritor) A1805E447.
I ended up using the Meritor/Axletech seal in the adapter, and the SKF seals in the transfer case at the yoke outputs.
Another challenge with the transfer case rebuild for me was the process of shimming the bearings to set end play. This was the main cause for concern with the original transfer case as well. I followed the manual and it says (depending on which one you go by) to put on the rear bearing cap and shims for the input shaft, tighten down the cap and set the end play on the shaft to .015". The problem was that the bearing on the rear, under the bearing cap seemed to move in and out of the bore an awful lot. It would not go all the way into the inside of the case but it would go just below the mating surface which caused the front bearing to move out a good 3/8" or so. At this point, I went ahead and hooked up the transfer case to the transmission and adapter and bolted it up. The adapter didn’t allow the bearing to move in and out, and I tried to move the shaft forward and backward from inside the transfer case, but there was no way for me to measure end play doing it this way. I concluded that the bores for the bearings in the original case were likely worn as there was also indications that at some point, the bearing was changed out (it was not the original bearing) due to a failure. The rear of the input shaft was tore up, and the bearing cap itself was cracked.
For comparison, I took a telescoping bore gauge and did a comparison with the other case that I have and it seemed to be tighter. I didn't put a mic on it, but the bore was definitely a bit smaller on the other case. It was at this point that I opted to just use the other case as the gears, shafts, and components all looked better anyway.
I did have difficulty in setting up the end play on the other bearings, but after some messing around with it, I eventually got it configured.
Another problem that I had was with the threads for the nut that secures the yoke on the rear output shaft. When I disassembled the case, I put the nut on the shaft and used a hammer to tap out the shaft. Well, I didn’t have the nut all the way down (important safety tip for next time!!) and I mushroomed the threads on the shaft slightly as well as on the nut. During the assembly process when I was installing the rear yoke, I foolishly tried to force the nut on using my impact wrench….super bad idea. I tore up the threads in the nut, stripped it out and made the threads on the shaft worse. At this point I stopped for the night (it was 11:30PM) to revel in my stupidity.
After determining that the threads in the nut and on the shaft were 7/8x14, I order a tap and die and got them cleaned up on the shaft (I had another nut from the other transfer case).
From that point on, the assembly went well. I did notice as I was putting the top cover on that the original springs for the balls that lock the shift forks were smaller on the original case. After closer inspection it looks as if they were cut down at some point. I put the longer springs on from the replacement case first and the shifting was extremely tight. I put the smaller springs in and the shifting seems to be much nicer. I concluded that this was a “mod” probably done at some point due to the lever being too tight to pull when shifting into 4WD.
The gasket kit that I ordered for the transmission did not come with any adapter gaskets that go between the adapter and the transfer case, so I had to make my own. I ended up using extra shims that I had as templates and they fit perfectly.
Finally, I was able to lower the transmission and transfer case into the frame and get it bolted up. I also filled both gear boxes with gear oil. Having the body off is nice….all I needed to do is pour the oil in from the top of the transmission where the gear shifter goes and I took the top off of the transfer case and did the same. On the transmission, you just fill until it comes out of the fill hole on the side. Same goes for the transfer case, but I ended up putting the plug in and adding about an extra ½ quart of gear oil to hopefully allow for additional lubrication of the upper end.

[Chaparralman1974]

Transfer case tear down pictures

[Chaparralman1974]

More transfer case pictures.

[Chaparralman1974]

Transfer case completed.

[clay68c10]

Nice work, and kudos for having the persistence to get the TC done right.
My friend in Wyoming swears by those T221's. They're pretty stout.

[KyleSeal]

Love this thread! Not a huge 4Wd guy (even though I have a 84 K30 and 4WD Toyota ). But the transfer case rebuild brings back memories of when I did it on my 84 (NP205/SM465)! It was meticulous but it was gratifying! Tracking down pieces and parts can be tough as well.

[Chaparralman1974]

Originally Posted by KyleSeal

Love this thread! Not a huge 4Wd guy (even though I have a 84 K30 and 4WD Toyota ). But the transfer case rebuild brings back memories of when I did it on my 84 (NP205/SM465)! It was meticulous but it was gratifying! Tracking down pieces and parts can be tough as well.

It has been indeed a lot of fun! I have received a lot of help from this forum...I have to call out Chuck (cbeerman) as he has helped me a ton on getting the rockwell back together. It was a challenge for sure, but I hope that I can get another 50+ years out of it. The only real snag in the rebuild was the rear output shaft....the manual calls for close to zero end play. After I got it all together, there is a very small amount of end play in it. I may have to take stuff apart again and remove some of the shims, but we will see.

I also plan on doing a rebuild on the other transfer case as well so that I have a spare. If nothing else, it is relaxing to work on this stuff.

I also did an about face on the front axle. I decided to go back to the original closed knuckle front axle. I have it about 90% rebuilt and it is installed on the frame. I will be updating the thread with pictures shortly.


Clay

[72 tigger]

You’re really doing things right. You’ll be thankful that you went through everything correctly

[Chaparralman1974]

4/4/2023 - 4/23/2023
Front Axle Swap…..Again!
I have come to the conclusion that I am a glutton for punishment and enjoy repeating work efforts….NOT!
After a lot of thought and back and forth, I have decided to stay with the original closed knuckle front axle on the truck. I had to sit back and rethink what my overall project goals are. First off, this truck will never be a daily driver….nor will it ever be driven off road. Moreover, it is unlikely that it will be driven more that on the weekends to go get ice cream or maybe to a car show or maybe to Home Depot to get a bag of grass seed. The point is, I realized that what I want is an original 1967 K20. So, out with the Dana 44 front disc brake axle and in with the closed knuckle original axle.
The original axle did have some issues. The driver side axle shaft was snapped in half, there was a huge dent in the front cover, and the ring gear had a chipped tooth. The tooth wasn’t a big deal to me. I simply ground down the rough edges with a small DA. The inner axle seals were clearly toast as well so I replaced those and did a complete and thorough cleaning of the inside of the axle.
The spindles were ok, but there was a slight groove on each of them where the grease seal rides. This was remedied by an SKF Speedi-Sleeve (99253). The bearings and races were all in good condition after cleaning in kerosene, so I reused those.
The brakes have been a bit of a challenge. First off the drums are Unobtanium! While I was able to have my original drums turned, the driver side has a warp in it. I can only think that this warp is my own fault as I beat on it pretty hard to get it off before I realized that you need to rotate the adjuster star inboard in order to bring the shoes in so you can get the drum off. I am going to try to get it straightened out somewhat, but I am on the lookout for a new set of drums.
The shoes were easy to find at rock auto, as well as some of the springs, but the rest of the brake hardware is a bit of a challenge to find as well. I know that the springs are fairly standard, and I imagine that I could search through bins of springs to locate ones that matched, but all in all, mine were not too bad, so I cleaned them up and decided to reuse them as there was no rust on them. Just grease and dirt.
All of the knuckle bearings were ok, save one so I replaced that one and picked up some new king pin shims. After getting the new wipers installed, both sides were filled with corn head grease.
I installed the spicer locking hubs and cleaned up the front tie rod and installed new ends.
Also worth noting is the lug studs for the front hubs. Originally, the truck had ½” studs. I wanted to upgrade to 9/16” studs. As it turns out, the knurled holes for the original studs is .625”. I found that the Dorman 610-181 studs have a .623” knurl and are only slightly longer. They fit like a glove and now I have updated studs for the front and rear.

[Chaparralman1974]

Here is the housing after cleaning showing the new seals and the chipped tooth on the ring gear.

[wrangler94]

Did you ever find a brake drum that would work for your front? I have a buddy who's looking for the same thing. He's got the same problem, k20 front brake drums.

[Chaparralman1974]

Originally Posted by wrangler94

Did you ever find a brake drum that would work for your front? I have a buddy who's looking for the same thing. He's got the same problem, k20 front brake drums.

Unfortunately, no not yet. I am still searching for them.


Clay

********** EDIT 12/2/2023 **********
For anyone interested, I did end up finding a brake drum that will work with the dana 44 closed knuckle front axle. Another member of the forum helped me find it. It is Raybestos 2008R. I believe that this drum was used for 1950's Chevy Trucks on the front axle. The lug holes will need to be drilled and reamed to match the lug studs. I upgraded my studs to 9/16", and if memory serves me correctly I had to ream the holes out to 5/8", but the drums fit perfectly otherwise.

[72 tigger]

Great progress!

[Short 3/4]

Funny how brake parts for something as common as a Chevy truck can be so hard to find. Was definitely the hardest part of my rebuild!

Don’t know if he’s still around but a guy named Craig had a business in Southern California called Drum Garden that specialized in impossible to find brake parts. Might be able to find him on the interwebs, if not I may be able to dig up his number.

One thing I learned is there are a number of applications for different years and manufacturers that all used the same 12x2” castings, then machined them to different specifications. For instance there is a Ford application that is just slightly larger ID than ours that was still available when I first did mine. There is a business in my area that re lines brakes for big trucks. Was able have my shoes re lined with thicker material than normal then re arched to match the larger drums. Apparently this is a common thing done on big rigs and this place certainly would not do it if it was not legit. I ran mine for several years that way until I came across the correct ones. They worked great and I still have them for spares. Whatever you use, I strongly recommend finding a place that can arch your shoes correctly, as it makes a huge difference in the performance of any drum brakes.

Return springs were another thing I was surprised weren’t available. Lots of places said they had them, but they were never right for 3/4 ton. Glad yours were all still usable

Project is looking great, keep up the good work
Tom

[Jason Banks]

Originally Posted by Chaparralman1974

Unfortunately, no not yet. I am still searching for them.


Clay

********** EDIT 12/2/2023 **********
For anyone interested, I did end up finding a brake drum that will work with the dana 44 closed knuckle front axle. Another member of the forum helped me find it. It is Raybestos 2008R. I believe that this drum was used for 1950's Chevy Trucks on the front axle. The lug holes will need to be drilled and reamed to match the lug studs. I upgraded my studs to 9/16", and if memory serves me correctly I had to ream the holes out to 5/8", but the drums fit perfectly otherwise.

I'm 99% sure I know the answer and your pictures also seem to confirm...

But, do the brake drums just slide off the spindle?

I pulled my spindle and hub as an assembly and can't seem to get them apart? I did take the 2 screws that hold them together and air hammered around the hub on the drum(before I just pulled them together). Had to quit for today, but I thought tomorrow I would parts washer the grease out of the hub and stick them in the sandblaster to make sure there's not paint/grime buildup causing a ridge at the ID of the drum. I say that, because when they were still on the axle. I could pry lightly between the backing plate and drum and see movement at the lug studs. I also lightly heated the drum in the same place. I'm trying to be gentle for fear of warping them like you thought you might have....

[Chaparralman1974]

Originally Posted by Jason Banks

I'm 99% sure I know the answer and your pictures also seem to confirm...

But, do the brake drums just slide off the spindle?

I pulled my spindle and hub as an assembly and can't seem to get them apart? I did take the 2 screws that hold them together and air hammered around the hub on the drum(before I just pulled them together). Had to quit for today, but I thought tomorrow I would parts washer the grease out of the hub and stick them in the sandblaster to make sure there's not paint/grime buildup causing a ridge at the ID of the drum. I say that, because when they were still on the axle. I could pry lightly between the backing plate and drum and see movement at the lug studs. I also lightly heated the drum in the same place. I'm trying to be gentle for fear of warping them like you thought you might have....

Yes, the drum should slide right off of the shoes. As long as you have removed the screws on the front face of the drum, it "should" slide right off. You most likely have a ridge as I did and if the shoes are siezed in place, then it will make for a fun time removing it. You may have to cut the pins on the back of the backing plate allowing the shoes to collapse somewhat. That should allow you a bit of movement to get the shoes off. You definitely don't want to beat too hard on the drums or you will mess them up. Even if you do though, the Raybestos 2008R's are a perfect fit provided you ream out the lug holes.

Good luck!
Clay

[Short 3/4]

Catching up on your build progress. Looking really good!
Glad to see you were able to make those hubs you like work. Don’t know if you’ve ever had a closed knuckle before, but I only unlock my hubs when going on the hi way. Around town I keep them locked as that’s the only way those upper bearings get any lubrication if you don’t wheel it regular. Parts will still outlive us all and the gas mileage will suck no matter what.
Hope you have Cornhead grease in those knuckles. Would sure be a shame to see that beautiful chassis sprayed in 90W.
Keep up the great work, that’s going to be one gorgeous truck
Tom

[Chaparralman1974]

7/1/2023 - 7/31/2023
Engine and Chassis Small Parts Cleaning and Installation
Now that the heat and humidity have arrived, I have been stuck in the garage (fortunately my garage has A/C) so I have shifted focus to the cleaning up and restoring of smaller parts that attach to the engine and chassis.
I started by doing a full rebuild / restoration of the distributor. My original plan was to go with either a Pertronix or HEI setup, but ultimately opted to just rebuild the original distributor that came with the truck. After doing a complete teardown and cleaning, I ended up ordering all new internals including a new vacuum advance, points, condenser, cap, rotor and distributor shaft bushings. The end result is a totally rebuilt distributor.
I also cleaned up and painted the exhaust manifolds, alternator, pulleys, and starter. The waterpump however was replaced with a new unit along with a new fuel pump. I was able to track down a NOS clutch inspection cover and got that installed as well.
My original intention was to reuse the brake lines, but upon further inspection I discovered that the lines were collapsed in some locations, so I will be replacing all the pre-bent lines with aftermarket components.
Speaking of brakes, I sand-blasted and painted all of the frame clips that attach the lines to the chassis and also cleaned up the parking brake components. I will be working on installing the parking brake cables next.
The front drums bear a little bit of discussion. I had a member of the 67-72 Chevy truck community reach out to me about a suitable replacement for the front drums. Specifically, Raybestos 2008R drums were a match for the original Dana 44. I ordered a set of these from Rock Auto and they were a perfect match for the front of my existing drum brake setup. The only issue was the size of the lug stud holes. I believe that these were originally for a 50’s to early 60’s setup with what appear to be 7/16” studs. The center bore and all other measurements were a near perfect match to my existing drums. I reamed out the lug stud holes to ⅝” and they fit like a glove!
I have a few odds and ends to still perform on the chassis, but I am now getting close to turning my attention to body work.

[Chaparralman1974]

A few more pictures.

[Chaparralman1974]

Here are a few pictures of the Distibutor rebuild.

[Chaparralman1974]

A little out of order, but here are a couple of pictures of the motor going into the chassis as well.