1977 K10 Stepside -The Grinch build

Welcome to the build or rebuild or version 4.??? of my 1977 chevy K10 we call The Grinch. I have owned this truck for many years and rebuilt it several times. I hope someone can learn from my mistakes or at least enjoy the pics. Any input would be really helpful. Pics will be added as we go. The ultimate goal is to have a decent daily driver that can cruise the highway. IT needs to be tough and able to haul camping gear and tools for side jobs. Eventually I want to take it to Moab and later Alaska. For work I often have the option to move to very remote and beautiful parts of the US. I want this truck to be able to go with me and get me out in the quiet spaces.

Current specs:
Year : 1977
Make /model: Chevy K10 Scottsdale Shortbed Stepside
Engine: 379cid 6.2L Diesel
Transmission: Sm465 Granny Low 4 speed
Transfercase: Np205 with JB Twinsticks and Ground rails
Front Axle: Dana 60 Pass side drop Low pinion $:56 gears and Limited slip
Rear Axle: Cooperate 14 bolt Full Float 4:56 gears Detroit locker Disc brakes from Ruff stuff
Lift: 4 inch tuff country HD Springs. ORD HD Front Shackles. Steering arm Block,Rear4 inch Shackle Flip from DIY4x with cross tied shackles. Bilstine shocks front and rear, 1 inch ORD body lift
Wheels and Tires: Recentered Military 8 bolt beadlock rims with PVC incerts. 37 inch Militarry MTR
Recovery: Front warn winch bumper , 8274 winch. Rear plate bumper
Camper: Contractor cap (Planning build)

Parts to install
Ranger Torque splitter III overdrive
Banks Sidewinder turbo kit
Rustproof and paint
Insulate and finish camper
Redo and build M101A1 trailer to match

I traded a garden tractor for this truck. A really cool 1962 wheel horse 552 garden tractor but a garden tractor i purchased for $125.00. The truck had been off the road for 10 years but was stored in a garage. It had rust and dents. The fuel leaked. the trans did not work. and the exhaust had fallen off. The seller had it on CL for $500.00 OBO so the trade was made and I took it home.

The truck

Yummm mold

The truck came from The grand son of the original owner. It was used as a farm truck in PA. it was ordered new with black paint. red pinstripe and red interior. The truck was a v8350,th350,np203 full time 4x4, 10 bolt front 12 bolt rear with 3:08 gears. No AC but it did have power brakes and steering. Well we went to get the truck inspected and the state of MA.... LEts just say they are not reasonable or logical. So it was time to get the truck road legal which ment fixing the rust....
New used bed $300

New used bumper $25

New used hood,doors,coresupport,grill,front fenders $300

Now we can pass state inspection!!!

All the colors of green
Last edited:
Now came Version 2
We wheeled it stock and had a blast but IT was time to get some ground clearance and fit some 34's.

DiY4x Shackle flip and cross tied shackles

Also started Painting truck 1 color... old army green and new tires 34 inch super swamper LTB bias ply (best tires she ran)

Front got some used rancho springs

The Front 10 bolt got a lock right locker. The NP203 got a part time SHAFT kit and super winch hubs

Scored This Warn Bumper and 8274 for $400. Rebuilt the winch with a kit from napa

Also swapped in a NP205 and JB fab twin sticks.... but soon found out the Th350 was not long for this world...

did well in the rocks tho...
So the trans took in some water. Normally a filter and flush would of worked but I wanted a granny gear any ways...

100 mile tow home Version 2 begins

out with the Th350/np205

Swap parts ready

Need to change the input shaft in the np205 from the 27 auto spline to the 10 spline

testing out the granny gear

of course the towing mirrors got ripped off by some trees. Trails here in the north east are tight tight tight and most people rock jeeps or yotas... Decided to get bigger tires and scored these old school gateway monster mudders... the GUMBOS 35x14.5r15 bias ply. Looked cool but Wide tires don't wheel well on the trails....

Added axle shims to correct pinion angle and ez inches to move axles

On To Version 3 . . . .
At this point I should of went back to 34's or skinny 36's and called it good but I wanted more or thought i did....

The 3:08 gears were not great so I decided to go 3/4 axles. This meant re gearing the front to 3:73 and adding 8 lug hubs and rotors. For the rear i got a 14 bolt out of a K20 that was a full floater and bought a Detroit locker out of a cucv.

14FF got a shave to smooth out the hoe it can become in the rocks.... this actually worked out real well for me but ate grinding discs

Front got a newer tierod from an 88 K5. Lockrite locker. and a home brew diffgaurd.

bought some used 15x10 8 lug wheels grinded my brake calipers and bolted them on also picked up a new daily driver Also smaller rear tires for towing
The 35's were too fat so I went for some Goodyear MT OZ's on 12 bolt Hutchinson beatdlocks... with 2 inch spacers

The wheels are awesome but heavy and tire size was truly limited. While the 350 was great it was also bone stock and got 12 MPG on the highway. I wanted better mpg and I wanted fuel injection. Being a broke college student I made the only logical choice. A GM 6.2 That I picked up used for 400 beans with only 15K documented miles fortunatly those pics will be added here later.
With the 6.2 on the high way with #:73 and 37's the truck would get 23mpg.... but it was a dog. With the sm465 you can cheat and use granny gear to get the beast rolling and offroad in Low range it was no real issue. I had 1 tons from a M1028 I parted out so they got swapped in after i sheered the steering arm off the 10 bolt. my highway MPG only went down to about 20 and the 4:56's work much better with the 37's
Picture HERE

Also with eh diesel swap I installed autometer gauges and buckets seats

Now onto Version 4....
I noticed I really use this truck for more mild wheeling and long highway runs... I over built it but never wanted to smash it up My new plan is to Lower it down alittle. I want to buy some 16 inch ford Econoline wheels and run skinny talll tires. I am thinking 36 or 38x11's. I have the OD and turbo to install as well. But the biggest change is the Contractor cap on the back...
on 39.5x14.5r16.5 inch boggers

The camper cap. Came off a ford f150 with the 6.5 bed. Fits almost perfect. The wood since has been bed lined and sealed.

The military trailer. M101A1. Might also get a contractor cap or be built more to haul bikes and row boat and my ct90. Not sure yet but hopefully we will get matching hubs and wheels to the truck.

Currently the truck is at a shop getting new cab mounts, rockers, cab corners, kickpanals , and floors. I would have liked to do the sheetmetal work myself but the time could be better utilized repainting the truck or installing the overdrive. I finally have some cash to spend but no time or place to do the work. My goal is to return this truck to being my daily driver and get back out there and enjoy it... Will keep updating this as we make progress. Remember the build is only part of the fun and this has been an ongoing project since 2009... how the time flys
Last edited:


In for the Square. Good work so far. I'm not a oil burner fan, but if it is working for you keep rocking it. Keep an eye on the balancer as it's a known reason why the 6.2's commit suicide.

I'm always happy seeing these old trucks getting used for play and work.


New member
WOW! What an outstanding build and truck. I love seeing it pull the military trailer. Can't wait to see where she goes from here.