BigT
Junior Member
- Joined
- Oct 17, 2024
- Posts
- 22
- Reaction score
- 48
- Location
- Selah, WA
- First Name
- Tim
- Truck Year
- 1978
- Truck Model
- Scottsdale K20
- Engine Size
- 350
I grew up with Squarebody Chevies, as my dad had 3 or 4 of them over the years; I even learned to drive in a '75 1/2 ton 4X4 manual hauling hay bales. After about 20 years without one around, I recently bought an almost entirely cancer-free '78 Scottsdale K20 for my daily driver. Mildly built 350 w/ 4 bbl Quadrajet, TH400, NP203, and 4:56 gears!! Low, low!! I also have the build sheet, and it's almost entirely stock. Factory A/C (missing a bunch of parts, including the compressor), cruise control (transducer is there, but missing the rest), and the HC4 4:56 gears. The underside of this beast looks new!!
I could use some advice from you squareheads on a couple of things:
1. I know the gears came with the truck, since they are on the build sheet. I looked the truck up on the build option chart posted elsewhere on this forum, and it would appear that they must have been special ordered, as the charts say that gear ratio was only offered stock on the K30 one-tons. Since they were put on this truck by Chevy, does that mean that other rear-end components were likely beefed up as well, or could the 4:56 gears just be paired up with the standard 3/4 ton axles, etc.? I ask because I may want to swap both front and rear gear sets to 4:10s at some point in the future, but I'm not sure what all I will need to do that.
2. Come next summer, I will want to get the A/C working, and I ordered the whole OEM style shooting match from LMC to have on hand when the time comes. LMC did not offer all of the lines, however, as you can see in the attached diagram circled in red. Can you guys tell me what that part is and where I might locate it?
3. I also have no idea which compressor to get. I've never had one of these trucks with A/C in it, so I don't know what I am looking for. Is there one out there that uses the newest refrigerant, or are they all R134A?
Thanks a lot for your help in advance!!
Tim
PS - Yes, I know the grille is not the right one for that truck - it's already been swapped out with the right one, just haven't taken a new pic yet!!
I could use some advice from you squareheads on a couple of things:
1. I know the gears came with the truck, since they are on the build sheet. I looked the truck up on the build option chart posted elsewhere on this forum, and it would appear that they must have been special ordered, as the charts say that gear ratio was only offered stock on the K30 one-tons. Since they were put on this truck by Chevy, does that mean that other rear-end components were likely beefed up as well, or could the 4:56 gears just be paired up with the standard 3/4 ton axles, etc.? I ask because I may want to swap both front and rear gear sets to 4:10s at some point in the future, but I'm not sure what all I will need to do that.
2. Come next summer, I will want to get the A/C working, and I ordered the whole OEM style shooting match from LMC to have on hand when the time comes. LMC did not offer all of the lines, however, as you can see in the attached diagram circled in red. Can you guys tell me what that part is and where I might locate it?
3. I also have no idea which compressor to get. I've never had one of these trucks with A/C in it, so I don't know what I am looking for. Is there one out there that uses the newest refrigerant, or are they all R134A?
Thanks a lot for your help in advance!!
Tim
PS - Yes, I know the grille is not the right one for that truck - it's already been swapped out with the right one, just haven't taken a new pic yet!!
