Author Topic: 81 GMC 2500 350 block High Sierra Camper Special Restoration Project  (Read 774 times)

Offline tnclark1970

  • New Users
  • Posts: 1
  • Newbie
Hello, I am new to forum and I have owned a 1981 GMC for sevveral years.Been close to selling  a few times but since the body and frame are still quite good (engine compression is 110 unofficially) , it still runs...I think I would like to start restoring it because I love the body and how it handles all my flower farm materials/lumber etc. I am not a mechanic but have a few who are willing to work on it here and there. I am looking for info on
1) what tire/rim options are for this truck it has 8 lugs and 16.5 at the moment hard to find 16.5 tires so far
2)muffler options
3) maybe how long it will run at 110 compression?

Any tips, advice or info on this model would be great!

Offline JohnnyPopper

  • Senior Member
  • ****
  • Posts: 2526
  • Old Goof
Re: 81 GMC 2500 350 block High Sierra Camper Special Restoration Project
« Reply #1 on: June 06, 2023, 02:27:35 PM »
Welcome from So Cal San Diego!

Aftermarket wheels are plentiful, depends on your taste, that goes for mufflers- loud or quiet, or somewhere in between.

110 across the board? Did you check what the stock spec is for that year/model/size? I would start there.
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 Shifty

  • Junior Member
  • ***
  • Posts: 937
  • I bleed Bowtie red...
Re: 81 GMC 2500 350 block High Sierra Camper Special Restoration Project
« Reply #2 on: June 06, 2023, 05:14:25 PM »
1981 had low, low compression, if the 110 is roughly the same on all cylinders, and doesn't use oil excessively, I wouldn't worry.

Welcome from AZ!  8)
« Last Edit: June 07, 2023, 09:15:44 AM by Shifty »
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline Mr Diesel

  • Frequent Member
  • **
  • Posts: 325
  • Aaron
Re: 81 GMC 2500 350 block High Sierra Camper Special Restoration Project
« Reply #3 on: June 06, 2023, 07:33:58 PM »
For tires check Walmart.com. Distributors all over the country sell on their website. They can ship directly to your house and have great prices. Select tires that have lots of good reviews.
1976 C20 Crewcab, 6.2L/SM465
1982 K30 Crewcab , 427TD/TH400
1983 C30, 6.2L/TH400
1983 K30 Crewcab 454/700R4
1986 K10 350/400. 1989 K30 cab/chassis 454/SM465