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 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 12-01-2014, 06:08 PM   #1
MOTORHEAD383
Registered User
 
Join Date: Aug 2014
Location: ahwahnee CA.
Posts: 11
74 k20 speedometer dosn't fit

I have a 74 k20 and i found a 77 speedo but it dosnt fit for some reason. It seems like its too deep. Is there a difference between gauges 74-77?
MOTORHEAD383 is offline   Reply With Quote
Old 12-01-2014, 06:16 PM   #2
old Rusty C10
Robert Olson Transport
 
old Rusty C10's Avatar
 
Join Date: Oct 2002
Location: recent transplant to NC USA
Posts: 20,310
Re: 74 k20 speedometer dosn't fit

it should fit the only difference in depth is tach and just gauges.. Sometimes you have to play with them to get them to seat... I had to tuck the bottom under the lip and slowly massage it in
__________________
Bob



1951 International running on a squarebody chassis


"If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board"
http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!)


PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport

Live each day to the fullest.. you never know when fate is going to pull the rug out from under you...
I hate cancer!!
old Rusty C10 is offline   Reply With Quote
Old 12-01-2014, 10:04 PM   #3
MOTORHEAD383
Registered User
 
Join Date: Aug 2014
Location: ahwahnee CA.
Posts: 11
Re: 74 k20 speedometer dosn't fit

I think i found out why. I think the gauge cluster is out of a newer truck it has a cutout for the speedo cable and a seperate cutout for what looks like a plug in for something
MOTORHEAD383 is offline   Reply With Quote
Old 12-01-2014, 10:11 PM   #4
motornut
78K & 79C Jimmys
 
motornut's Avatar
 
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
Re: 74 k20 speedometer dosn't fit

yes some have the speedo clip on the plastic houseing,some on the metal under it
hole might be the one for the Vspeed sensor
Attached Images
  
__________________
John
1978 GMCJimmy4X4-350/203
1979 GMCJimmy4X2-305/350

Last edited by motornut; 12-01-2014 at 10:31 PM.
motornut is offline   Reply With Quote
Old 12-01-2014, 10:48 PM   #5
MOTORHEAD383
Registered User
 
Join Date: Aug 2014
Location: ahwahnee CA.
Posts: 11
Re: 74 k20 speedometer dosn't fit

Its the top one. Whats the difference between the 2 housings. The speedo i have bottoms out on the housing and dosn't seat all the way.
MOTORHEAD383 is offline   Reply With Quote
Old 12-01-2014, 11:05 PM   #6
MOTORHEAD383
Registered User
 
Join Date: Aug 2014
Location: ahwahnee CA.
Posts: 11
Re: 74 k20 speedometer dosn't fit

Name:  2014-12-01 18.58.57.jpg
Views: 120
Size:  52.0 KB
it bottoms out on these 2 screws. Would it mess anything up if i took them out
MOTORHEAD383 is offline   Reply With Quote
Old 12-01-2014, 11:14 PM   #7
motornut
78K & 79C Jimmys
 
motornut's Avatar
 
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
Re: 74 k20 speedometer dosn't fit

Quote:
Originally Posted by MOTORHEAD383 View Post
Attachment 1331678
it bottoms out on these 2 screws. Would it mess anything up if i took them out
I wanted to switch speedos and noticed it wouldn't fit.
that's a 79 and 88,can't you make holes for them?
__________________
John
1978 GMCJimmy4X4-350/203
1979 GMCJimmy4X2-305/350
motornut is offline   Reply With Quote
Old 12-02-2014, 12:18 AM   #8
MOTORHEAD383
Registered User
 
Join Date: Aug 2014
Location: ahwahnee CA.
Posts: 11
Re: 74 k20 speedometer dosn't fit

I just took them out. There not holding anything and they dont connect to anything
MOTORHEAD383 is offline   Reply With Quote
Old 12-02-2014, 08:45 AM   #9
motornut
78K & 79C Jimmys
 
motornut's Avatar
 
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
Re: 74 k20 speedometer dosn't fit

Quote:
Originally Posted by MOTORHEAD383 View Post
I just took them out. There not holding anything and they dont connect to anything
Cool
__________________
John
1978 GMCJimmy4X4-350/203
1979 GMCJimmy4X2-305/350
motornut is offline   Reply With Quote
Old 12-02-2014, 11:58 AM   #10
tlawre87
Registered User
 
tlawre87's Avatar
 
Join Date: Jun 2012
Location: Meeker, ok
Posts: 146
Re: 74 k20 speedometer dosn't fit

Remember your 74 is wired for an Ammeter. The 77 will have a volt meter.
http://www.73-87.com/7387garage/inte...achometers.htm
__________________
Trevor
74 C20...work in progress.
04 Saturn Ion...Daily Driver
tlawre87 is offline   Reply With Quote
Old 12-04-2014, 11:25 PM   #11
MOTORHEAD383
Registered User
 
Join Date: Aug 2014
Location: ahwahnee CA.
Posts: 11
Re: 74 k20 speedometer dosn't fit

I switched the wiring harness to the 77
MOTORHEAD383 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 09:46 PM.


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