Question for the Pros

[CSFJ]

Wasn’t sure if vacuum pumps were the go to or not. I don’t mess with the diesels much at all, we used to have a 6.2 c10 on the farm but that was about it lol

They put vacuum pumps on them, but I'm not sure if it's enough to run the brake booster. Usually, about the only thing hooked to them would be the trans modulator.

 

[78C10BigTen]

From what I’ve seen gas doors are a hit and miss through the 70’s, I’ve seen earlier ones with them while later ones don’t and vice versa it’s all over the place really lol. My 79 has gas doors but also has dual tanks. My buddy’s 77 had them as well but he just picked up a 79 c10 diesel that I’m pretty sure doesn’t have doors I can’t remember now.

But also with that 79 it’s a 350 olds diesel and an olds th400, but it’s a c10 and has hydroboost, so that doesn’t seem like a good indicator to me. Maybe it had hydro boost just because it’s diesel? I’m not sure.

My 78 c10 has dual tanks and no doors

 

[bucket]

'79 was the first year for fuel doors. The first FULL year at least. I sort of remember reading that the fuel doors may have been on some very late production '78 pickups, but I've never seen an original one.

 

[Dooley]

This is a C20 3+3 that was mostly converted to a C30. If the driver door is original, it specifies 16x6.5" wheels, Duallys were 16x6". The truck also has vacuum assist brakes and has a GVW of 8600 LBS. Duallys had 10k GVW and hydroboost brakes. Based on how close the rear drums are to the springs I would guess the rear end is the narrowed chassis cab rear end. I can't read the other door tag, but it gives the production date of the truck on the upper left of the tag. The last clue that tells me its a 3/4 ton is there is no provision in the roof for marker lights.

Either way, it looks like it would be a fun project.

Not true on the 70's duallies.
I ordered/bought several and until the 80's models I had to order 16" tires as an option. The standard wheel/tire configuration on the duallies were 16.5.
This truck in question is most likely a 3/4 ton 3+3 that has had a dually rear end and bed added.
No cab lights on cab also. Standard on 30 series light trucks.

 

[Billy]

i would pass, but that's just me.

And me

 

[CSFJ]

• How is a one ton suspension bolted to a one ton frame scarier than half the engine/trans swaps or lift kits that have been done to these trucks. At least this one was close enough to create some question as to what it started as. I mean hell, you've got people in this world that would pull a v8 to install a v6, and think they've got something special.

 

[Big Chip]

• How is a one ton suspension bolted to a one ton frame scarier than half the engine/trans swaps or lift kits that have been done to these trucks. At least this one was close enough to create some question as to what it started as. I mean hell, you've got people in this world that would pull a v8 to install a v6, and think they've got something special.

I've heard of a guy doing that. I think it was on a different forum though. I think it was a mileage thing if I remember correctly.

 

[Old77]

that squarebody Honda mod

 

[AzGeo]

Fuel caps instead of doors is 77' and older . My 76' had caps, my 79' has doors . The front disc brake pads are the same C20/C30 on 2 wheel drives . There were 8200 GVW and 8600 GVW C20's , and they both used corporate rear ends . This deal looks like a complete "rebuild", and is not an actual C30 dually . By the way, the 1973 duallys had vacuum power brakes, (I had one) and the hydro boost systems were started in C30's in 1974 . Return fuel pump systems (for vaporlock) started in 1976 .

In the photos above you do not have a "camper special" (C20 or C30) since I don't see any rear sway bars . The duallys had rear sway bars even without being a "camper special", and used the Dana rear end . The dual wheel "cab a chassis' trucks", also did not have the rear sway bars unless it was special ordered to become a motor home (Open Road brand among others)

 

[bucket]

Fuel caps instead of doors is 77' and older . My 76' had caps, my 79' has doors . The front disc brake pads are the same C20/C30 on 2 wheel drives . There were 8200 GVW and 8600 GVW C20's , and they both used corporate rear ends . This deal looks like a complete "rebuild", and is not an actual C30 dually . By the way, the 1973 duallys had vacuum power brakes, (I had one) and the hydro boost systems were started in C30's in 1974 . Return fuel pump systems (for vaporlock) started in 1976 .

In the photos above you do not have a "camper special" (C20 or C30) since I don't see any rear sway bars . The duallys had rear sway bars even without being a "camper special", and used the Dana rear end . The dual wheel "cab a chassis' trucks", also did not have the rear sway bars unless it was special ordered to become a motor home (Open Road brand among others)

C20's and C30's actually use different calipers, pads and steering knuckles. At least in the 80's.

C20's do however share pads with a C10, as they share the caliper design.

Edit-
And again, '78 retained exposed fuel caps too.