Author Topic: Dually conversion  (Read 1872 times)

Offline ChunkyRed

  • Newbie
  • Posts: 3
  • Newbie
Dually conversion
« on: August 18, 2020, 08:50:40 PM »
hello everyone, new to the forum, I have a 74 c10 with a shortbed dually bed, it has a 5 lug setup now but I'm wanting to convert this truck into a real dually then eventually install some semi wheels on it, so what is needed to convert this truck into a dually any help will be greatly appreciated, its a 74 c10 2wd.

Offline JohnnyPopper

  • Senior Member
  • ****
  • Posts: 1654
  • Old Goof
Re: Dually conversion
« Reply #1 on: August 19, 2020, 01:13:08 AM »
Sounds like you want to convert to a C30.

Start looking for a rear axle, and front suspension components. Same year would help but not totally required.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline ChunkyRed

  • Newbie
  • Posts: 3
  • Newbie
Re: Dually conversion
« Reply #2 on: August 23, 2020, 07:16:09 PM »
Ok JohnnyPopper thank you for the response, any tips or something to consider when looking for an axle? I was told the leaf spring lengths could be different.

Offline JohnnyPopper

  • Senior Member
  • ****
  • Posts: 1654
  • Old Goof
Re: Dually conversion
« Reply #3 on: August 24, 2020, 01:05:21 PM »
I would look for a cheap shot out C30 whose frame is in good shape.

You will have all the running gear to compare right in front of you, and you may just opt to shorten the frame to fit your cab and bed then transfer the cab to your rebuilt frame and running gear.

The other option will be to switch our the running gear to your frame. The C30 frame is thicker, stronger though.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Stewart G Griffin

  • Senior Member
  • ****
  • Posts: 3284
Re: Dually conversion
« Reply #4 on: September 08, 2020, 07:41:07 PM »
i'm pretty sure this has been discussed many times, but are the 1/2 ton frames and 3/4-1ton frames the same shape?   Or are they thicker, heavier AND different dimensioned?


Offline JohnnyPopper

  • Senior Member
  • ****
  • Posts: 1654
  • Old Goof
Re: Dually conversion
« Reply #5 on: September 09, 2020, 04:24:55 PM »
I've heard here that they are thicker.

As for different dimensions, When they rolled out a C10 and a C30 back in the day, and they looked identical in size of cab and bed, I made the assumption that they're interchangeable. Probably wrong?
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Stewart G Griffin

  • Senior Member
  • ****
  • Posts: 3284
Re: Dually conversion
« Reply #6 on: September 10, 2020, 07:33:40 AM »
What i was trying to get at is, could you just take the spring hangers, springs, rear end out of a 1-ton and bolt it into a 1/2 ton chassis?

Probably not though....

Offline zieg85

  • Global Moderator
  • Senior Member
  • ****
  • Posts: 7388
    • 73-87 GM squarebody extended cab and conversions up to 91 R/V series
Re: Dually conversion
« Reply #7 on: September 10, 2020, 12:53:09 PM »
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline zieg85

  • Global Moderator
  • Senior Member
  • ****
  • Posts: 7388
    • 73-87 GM squarebody extended cab and conversions up to 91 R/V series
Re: Dually conversion
« Reply #8 on: September 10, 2020, 01:00:59 PM »
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline JohnnyPopper

  • Senior Member
  • ****
  • Posts: 1654
  • Old Goof
Re: Dually conversion
« Reply #9 on: September 10, 2020, 04:01:23 PM »
I sure like being right about being wrong! Wowser!!!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline 78 Chevyrado

  • Z62 ON-ROAD
  • Site Supporters
  • Senior Member
  • ******
  • Posts: 2636
    • My Photobucket Site
Re: Dually conversion
« Reply #10 on: April 27, 2021, 04:29:00 AM »
C10 upgraded won't have the weight ratings a c20 or c30 would have.  the frames are different.  c20 is heavier than a c10 and c30 is heavier and thicker than c10 or c20.  Just don't do the dually upgrade and think you'll have c30 towing and hauling capabilities.

But if it's just for looks go for it, but don't assume a GVWR above 6400lbs at best.
Kenny

1978 C-20, 350/400, 3.73, Graystone Metallic, Raceline Renegade 8 Wheels - 18x8.5, 275/70R18 BFG KO's