1968 Chevy K10 SWB Overlander

[locrwln]

locrwin, the truck is currently in the shop getting a new exhaust. I will upload a picture of the SPID as soon as possible! How much do you think it would cost to put disc brakes in the front?

Looking forward to it. The cost is: it depends. How handy are you and how good are you at scrounging for deals? I can't remember on the 68's if they were open or closed knuckle front axles. If closed then go for a complete front d44 from a later model truck, usually someone is parting out a truck on CL, so that should help. The big question will be what gears you currently have, as you will want to make sure they match front and rear. If the front axle is open, then all you have to do is swap from the balljoints out. I would also switch out to later model axle shafts as well. GM used 260 joints in their 1/2t of that era and 297/760's sized joints were used on 3/4t axles, by '73 they were using 297/760's on all d44 front axles.

Oh man, don't get too crazy with that truck doing something foolish like a Cummins swap. Not that doing a Cummins swap is foolish but those old trucks are getting very hard to find in unmolested condition. By the time you install a Cummins, a transmission that would live behind a Cummins, and then the axles to handle a Cummins there wouldn't be anything left of that truck.

If it where mine, I would add a power steering gearbox and pump, power brake booster and front disk brake axle from a 1971 or 1972 or even '73-'87 (and sway bar) then add a HEI distributor and call it good. At the most maybe add an overdrive transmission just to help with the highway cruising. 292's are great engines with great low end torque! I would love to have an old truck with a 292! Anybody can have a V8 and any farmboy with a welder can glue a Cummins in just about anything but 292's are rare! Don't ruin this truck please :drool:

…..or just sell me the truck and go buy yourself a Cummins truck :coffeedrink:

I have to agree with Larry, keep it simple and stick to the neccessary upgrades that make it safer/easier to drive. I would caution against a cummins as well, too much motor without a lot of strength improvements to not only the axles, but the frame as well. 1100lbs of weight and dial-a-torque are rough on things not designed for it. Not to mention the "paint shaker" likes to find and create stress cracks, pretty much everywhere...

Put me in line to buy behind Larry. Always a big fan of those trucks. My wife had a '69 SWB, 1/2t, 4wd, Custom, I had a '72 LWB, 1/2t, 2wd, Cheyenne Super (shoudn't have let either go) and my buddy had a '68 2wd, swb, Custom, not to mention I can't remember how many my various uncles and cousins had when I was growing up.

Jack

 

[snekvasil]

Oh man, don't get too crazy with that truck doing something foolish like a Cummins swap. Not that doing a Cummins swap is foolish but those old trucks are getting very hard to find in unmolested condition. By the time you install a Cummins, a transmission that would live behind a Cummins, and then the axles to handle a Cummins there wouldn't be anything left of that truck.

If it where mine, I would add a power steering gearbox and pump, power brake booster and front disk brake axle from a 1971 or 1972 or even '73-'87 (and sway bar) then add a HEI distributor and call it good. At the most maybe add an overdrive transmission just to help with the highway cruising. 292's are great engines with great low end torque! I would love to have an old truck with a 292! Anybody can have a V8 and any farmboy with a welder can glue a Cummins in just about anything but 292's are rare! Don't ruin this truck please :drool:

…..or just sell me the truck and go buy yourself a Cummins truck :coffeedrink:

I'm beginning to see your and locwrin's point...and I totally agree. I'm going to keep the truck as stock as possible. I am planning on putting a power steering gearbox and pump in the truck as soon as I can afford it. I'm going to stick with the drum brakes for a while; I just had them replaced and they're working fine for the time being.

What exactly is an HEI distributor? Also, do you know of any way I can prep the engine for fairly deep water crossings? Everything is so open right now...and I can't really figure out a way to snorkel the engine with the carburetor. Also, the current distributor is not exactly water-tight. If it gets wet, it won't work until it dries out. Meaning I can only go through 2-3 feet of water at most...

 

[Desert Dan]

What a great truck and history of your grampa. I'd keep it a stock as possible but upgrade front brakes to disc and get a new master cylinder and maybe add power steering.

It is more valuable all stock!

There are lots of other trucks with a Cummins engine around.

 

[pappawheely]

You have a stout reliable truck there. Like others, I would keep that inline 6, upgrade the brakes and steering and drive it to the ends of the earth. If it ain't broke, don't fix it!

 

[1leglance]

I have my granddads 72 Chevy truck and now my younger son is about to have it as his first vehicle.
We also have a 70 Suburban as our family camping rig...
Old Iron is great!


What part of New Mexico are you in? We have a good group of old iron folks out here in the Southwest and it would be great to have you along.
Also go to www.67-72chevytrucks.com and you will learn anything and everything you ever wanted.

That 292 inline 6 is a great motor and like others have said the most I would do would be a gearvendors overdrive if the highway speeds really bother you.
Deep water should not be something you do enough of at a level deep enough that you need to do anything to that engine.
With 33in tires and a mild lift you should be good to 24-30in I would think and a little WD-40 on the distributor after a crossing if she sputters would be enough.
Throw some die-electric grease on all the electrical connections also if you want.

Really like others have said you should just love it and live with it for a while.

 

[locrwln]

One other thing I will add is depending on the gearing, (I suspect either 4.10's or 4.56's pretty common for GM 4wd's of that era) you might be able to get away with some "rubber" overdrive to help with the driveability. The great thing about that 292 is that it really only has one speed.:victory:

Doesn't matter if it is loaded or empty, if there is a hill that it climbs at 50mph, it will do that regardless of the load (they are all about torque), so some skinny 33's should help lower the rpms and shouldn't affect the overall "feel" of power.

Here is a quick rundown of HEI and why it is an upgrade over your points.
http://en.wikipedia.org/wiki/High_energy_ignition

Jack

 

[toylandcruiser]

Isn't swb, Short wheel base? Not short wide bed?

 

[NMC_EXP]

You have a rare jewel there I agree about staying close to stock.

Personal nostalgia trip: My first pickup was a 1967 GMC 3/4T, 305 CID V6, 2WD, 4 spd w/granny low and 4.56 Positrac gears.

That's right...a 305 CID V6. It also came in 351, 401, 478 and a 702 CID V12 twin V6.

Of the 2WD trucks I've owned, this was my favorite. I was young and broke and could not afford to feed it's 12 MPG habit so I let it go.

re: the old GM V6's from Wikipedia:
GMC Truck produced a unique 60° V6 engine from 1960 through 1978. The engine was available in 305, 351, 401 and 478-cubic-inch (5.0, 5.8, 6.6, and 7.8 respectively L) versions. In late production there was also a 432-cubic-inch (7.1 L) version with enlarged crankshaft journals. GMC also made a 637-cubic-inch (10.4 L) 60° V8 with single, not twin balance shafts using the same general layout(bore & stroke) as the 478. The 637 V8 was the largest production gas V8 ever made for highway trucks. Finally, there was a 702-cubic-inch (11.5 L) "Twin Six" V12, which was basically two 351s placed end-to-end with a common block and crank. A Diesel version of the 351, 478 and the 637 were called the ToroFlow.

Jim

 

[east_tn_81]

First of all nice truck. I am glad I am not alone in saying keep that inline 6. The cost of a cummins the work and time do not out way the benfit. Those old inlines are bullet proof. The low end torque is amazing. In my personal experience the relability of a inline 6 with out all of the computer s#*t on it is just as good as a diesel. I have seen the ford inline 6 (300 cu in) with over 400,000 miles on them. Save yourself some time money and frustration and stick with the orignal motor, you wont regret it.

 

[Larry]

What exactly is an HEI distributor? Also, do you know of any way I can prep the engine for fairly deep water crossings? Everything is so open right now...and I can't really figure out a way to snorkel the engine with the carburetor. Also, the current distributor is not exactly water-tight. If it gets wet, it won't work until it dries out. Meaning I can only go through 2-3 feet of water at most...

As Jack linked regarding HEI electronic ignition…. HEI is GM’s electric ignition that began in 1975. It is a very robust and reliable ignition system with a slight bump in performance. Your truck currently has breaker point ignition which is stone age simple, requires a lot of maintenance but yet not very robust or reliable, which some people may disagree (remember back in this truck era a tune up was required about every 10,000 to 20,000 miles. I’ve owned 6 or 7 of these old trucks and have had issues with points on all of them. I learned at very young age how to replace points and hate them! After converting each one of the old trucks I’ve had over the years (and one boat with a 250 I6) to HEI there was never another issue. Some people with complain about ignition module failures inside the HEI distributor but part of that is due to people running cheap dime store part store made in Taiwan modules.

Even though I never suffered an ignition module failure on any of my old HEI trucks over the years I always kept a spare module in the glove box just in case, which is why Murphy probably never dealt me a failure. If are interested in an HEI conversion do some research as you would also need to replace the power wire from the ignition feed in the switch to the actual distributor as the breaker point ignition power wire is a resistor wire where it would not fully power a HEI distributor. Don’t be scared….it is a very easy swap. You should be able to find a straight 6 HEI distributor in NM pretty easy from any old 250 or 292 engine at the bone yard. All the Chevrolet I6 engines use the same distributor.

Can’t wait to see what you do with this ole girl :drool:

 

[snekvasil]

What part of New Mexico are you in? We have a good group of old iron folks out here in the Southwest and it would be great to have you along.
Also go to www.67-72chevytrucks.com and you will learn anything and everything you ever wanted.

I'm actually living in Indiana right now going to school at Purdue University. I'll be in New Mexico in March though...we should definitely do some off roading! I'll be in Silver City, NM...in the Southwest.

 

[snekvasil]

Here is a quick rundown of HEI and why it is an upgrade over your points.
http://en.wikipedia.org/wiki/High_energy_ignition

Jack & Larry,

I'll definitely look into swapping out to an HEI distributor. I'm convinced that it'd be a good swap. I think with that switch, along with the addition of power steering, will put my truck where I want it. I'm not ready to change out axles and/or brakes at this time. I won't be hauling anything or traveling at high speeds so I think the drums will work fine for now.

Thanks so much for your help! Any other advice is much appreciated...I'll post some more picks once the lift is installed and the new rims/tires are on. Again, thanks for your support and help!

 

[snekvasil]

Even though I never suffered an ignition module failure on any of my old HEI trucks over the years I always kept a spare module in the glove box just in case, which is why Murphy probably never dealt me a failure. If are interested in an HEI conversion do some research as you would also need to replace the power wire from the ignition feed in the switch to the actual distributor as the breaker point ignition power wire is a resistor wire where it would not fully power a HEI distributor. Don't be scared….it is a very easy swap. You should be able to find a straight 6 HEI distributor in NM pretty easy from any old 250 or 292 engine at the bone yard. All the Chevrolet I6 engines use the same distributor.

Would this HEI work with my truck?

http://www.jegs.com/i/Mallory/650/8548201C/10002/-1

Do I need to buy a special wiring as well?

 

[Larry]

Would this HEI work with my truck?

http://www.jegs.com/i/Mallory/650/8548201C/10002/-1

Do I need to buy a special wiring as well?

No, that won't work. That is for a V8...you need one for a Chevrolet I6 (inline 6). I'm not much of an aftermarket part fan anyway. Just go find a stock HEI dizzy at the junkyard. You probably won't find one in roadsalt ridden Indiana as these old trucks rusted away many moons ago, but you shouldn't have a hard time finding one when you get home to NM. Yes, you will need different spark plugs and wires too and the clean 12 volt power wire from the ignition switch that I mentioned above. There are lot of write ups on that on the website Lance mentioned.

 

[Mighty Dodge Ram]

A Cummins when the I-6 finally blows? You're gonna be waiting a loooooong time for that Cummins. X2 on the overdrive and all the other suggestions. You have a classic workhorse that will serve you well for many years to come. Good luck on the build! :sombrero: