The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-02-2003, 10:13 PM   #1
4t5acp
Registered User
 
Join Date: May 2003
Location: NC
Posts: 66
K10 vs K20

This is probably one of those stupid questions, but I figured the correct answer could be found here. What are the differences between a '72 K10 and K20 ,apart from the obvious different drive axles? I suppose the leaf spring packs are different, but am not sure.
4t5acp is offline   Reply With Quote
Old 06-03-2003, 05:21 AM   #2
JIMs70GMC
user # 2756
 
JIMs70GMC's Avatar
 
Join Date: Jun 2001
Location: Chesapeake, Virginia
Posts: 4,612
Only the rear springs are different. The fronts will have either two or three leaves depending on options. Mine had front and rear heavy duty springs, don't remember the RPOs. I also believe on 3/4 tons the rear suspension had 1" blocks. I have a pic in my sig link.
__________________
1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs
1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX
1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears
1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now.....
1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone.
1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed.

1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm
JIMs70GMC is offline   Reply With Quote
Old 06-03-2003, 10:09 AM   #3
Yukon Jack
Post Whore
 
Yukon Jack's Avatar
 
Join Date: Feb 2000
Location: Rose Hill, KS, USA
Posts: 12,686
The Chevy reproduction book that gives stats also shows a difference in frames. Both the K10 and K20 have 39,000 lb-test steel, but the K10's section modulus is 2.70 (KS-KE107 models) and 3.48 for the KS-KE109 models while the K20's section modulus is only 3.48. I think that has to do with the amount of give or elasticity the frame has.
__________________
1970 Blazer with a 400 sbc and 4" lift
1980 Pontiac Trans Am, 455 Oldsmobile
2012 Kawasaki Concours 14
Yukon Jack is offline   Reply With Quote
Old 06-03-2003, 10:18 PM   #4
4t5acp
Registered User
 
Join Date: May 2003
Location: NC
Posts: 66
Thanks for the info. - knew I had come to the right place to find out.
4t5acp is offline   Reply With Quote
Old 06-04-2003, 12:09 AM   #5
mshirey
Registered User
 
Join Date: Apr 2000
Location: San Diego, CA
Posts: 110
Great info regarding the section modulus. I assume that is the elastic section modulus. You are right in that this ratio is an indicator of the frame rail's ability to resist bending. This ratio is highly dependent on the geometry of the cross section of the frame rail. I always thought that the 3/4 ton frames must have a greater height which would provide for a larger section modulus. For those interested, the Elastic Section Modulus (S)=I/c. Where (I) is the moment of inertia of the geometric cross section and (c) is the largest distance from the neutral axis.
__________________
Mike
67' GMC Fleetside
mshirey is offline   Reply With Quote
Old 06-04-2003, 08:02 PM   #6
Vince M
Senior Member
 
Vince M's Avatar
 
Join Date: Apr 2000
Location: Orlando, FL
Posts: 1,076
Other differences...Correct me if I'm wrong though.
K10's were available as short beds, K20's were not.
K20's have 8 lug axles as you stated.

I can't say I've ever seen a K10 long bed..well not around here anywhere.
__________________
............................................................
68 Chevy CST SWB w/LS1, carb & 700r4. Golden Anniversary clone with a few improvements.
Vince M is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 08:03 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com