C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Speedo/ Odo Problem

Thread Tools
 
Search this Thread
 
Old Nov 21, 2020 | 07:01 PM
  #1  
Ray Romano's Avatar
Ray Romano
Thread Starter
Advanced
 
Joined: Sep 2019
Posts: 85
Likes: 21
Default Speedo/ Odo Problem

How can this be? My speedometer on my '70 works perfectly, but the odometer doesn't work at all! WTF? Doesn't that assembly work together?
Reply
Old Nov 21, 2020 | 07:17 PM
  #2  
Dynra Rockets's Avatar
Dynra Rockets
Burning Brakes
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Oct 2012
Posts: 1,152
Likes: 252
Default

There are a little tiny plastic gears to make it all work together. One of your little tiny plastic years has failed
Reply
Old Nov 21, 2020 | 07:26 PM
  #3  
Ray Romano's Avatar
Ray Romano
Thread Starter
Advanced
 
Joined: Sep 2019
Posts: 85
Likes: 21
Default

Originally Posted by Dynra Rockets
There are a little tiny plastic gears to make it all work together. One of your little tiny plastic years has failed
In the transmission or the speedometer?
Reply
Old Nov 21, 2020 | 07:33 PM
  #4  
Dynra Rockets's Avatar
Dynra Rockets
Burning Brakes
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Oct 2012
Posts: 1,152
Likes: 252
Default

Speedo. If the mph is working then the trans and cable are fine.
Reply
Old Nov 21, 2020 | 07:44 PM
  #5  
Ray Romano's Avatar
Ray Romano
Thread Starter
Advanced
 
Joined: Sep 2019
Posts: 85
Likes: 21
Default

I suppose this would require the removal of the dashboard. yuk.
Reply
Old Nov 21, 2020 | 08:50 PM
  #6  
bruiser's Avatar
bruiser
Melting Slicks
15 Year Member
Active Streak: 30 Days
Active Streak: 60 Days
Active Streak: 120 Days
 
Joined: Feb 2007
Posts: 2,709
Likes: 269
From: S.E. MI
St. Jude Donor '15
Default

Check your trip odometer cable, might not be pulled out all the way
Reply
Old Nov 22, 2020 | 12:58 AM
  #7  
4-vettes's Avatar
4-vettes
Race Director
15 Year Member
Liked
Loved
Top Answer: 1
 
Joined: Nov 2006
Posts: 13,282
Likes: 7,865
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
Default

won't matter. odo is going to turn regardless. unless of course those little plastic gears are stripped. looks like you need a new speedo.
Reply
Old Nov 22, 2020 | 08:57 AM
  #8  
Ray Romano's Avatar
Ray Romano
Thread Starter
Advanced
 
Joined: Sep 2019
Posts: 85
Likes: 21
Default

Originally Posted by bruiser
Check your trip odometer cable, might not be pulled out all the way
Ya mean there are TWO cables, one for the speedo and one for the odometer?
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

5 Best & 5 Most Overrated Corvette Track Packages of All Time!

 Joe Kucinski
story-1

Every 2027 Corvette Engine Explained

 Joe Kucinski
story-2

Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

 Verdad Gallardo
story-3

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-4

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-5

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-6

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-7

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-8

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-9

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
Old Nov 22, 2020 | 10:02 AM
  #9  
Dynra Rockets's Avatar
Dynra Rockets
Burning Brakes
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Oct 2012
Posts: 1,152
Likes: 252
Default

Originally Posted by Ray Romano
Ya mean there are TWO cables, one for the speedo and one for the odometer?
no. there is one cable to the speedo. search this forum or youtube for speedo repair. it is possible to fix yourself but takes patience, good eyes and tiny tools. there are a handful of speedo repair places around the country you can send it to also

Last edited by Dynra Rockets; Nov 22, 2020 at 10:03 AM.
Reply
Old Nov 22, 2020 | 10:31 AM
  #10  
Eric P's Avatar
Eric P
Drifting
Liked
Loved
Community Favorite
Top Answer: 1
 
Joined: Aug 2019
Posts: 1,511
Likes: 498
Default

Here’s someone that just did this
https://www.corvetteforum.com/forums...rs-repair.html
Reply
Old Nov 22, 2020 | 12:58 PM
  #11  
bruiser's Avatar
bruiser
Melting Slicks
15 Year Member
Active Streak: 30 Days
Active Streak: 60 Days
Active Streak: 120 Days
 
Joined: Feb 2007
Posts: 2,709
Likes: 269
From: S.E. MI
St. Jude Donor '15
Default

Originally Posted by Ray Romano
Ya mean there are TWO cables, one for the speedo and one for the odometer?
The trip odometer cable is the one you use to reset back to zero. It is below the steering column.
Reply
Old Nov 24, 2020 | 01:03 AM
  #12  
mongoose87's Avatar
mongoose87
Racer
Liked
Loved
Community Favorite
 
Joined: Jun 2017
Posts: 495
Likes: 85
Default

I just did this repair.
The issue is the gear in the speedometer, so the dash needs to come out.
The question is not IF the plastic gear is stripped, it's why. The gear is plastic for a reason, and that's to keep the speedometer working if there is binding in any of the other gears.
For me, it turned out the numbered rollers that became frozen because of corrosion on the shaft they ride on.

speedometer removed from dash

speedo removed from face with stability plate removed

you have to use a punch to knock out the retaining bushing that holds the black plastic gear in place

this is the gear that is designed to strip when there is too much binding or resitance in the subsequent gearing


Notice the dark spot on the shaft


The bad thing is removing the dash is a huge pain in the ***.
The good thing is it can be fixed by buying a relatively cheap new gear (numbered 1604) and a lot of time. For the cost of a new speedometer, I would say it's worth trying to do it yourself.
Reply
Old Nov 24, 2020 | 03:03 PM
  #13  
7T1vette's Avatar
7T1vette
Team Owner
15 Year Member
Community Builder
Community Influencer
Top Answer: 5
 
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Default

You have the ideal situation: Speedo works....but the car never shows more miles of use!!
Reply

Get notified of new replies

To Speedo/ Odo Problem





All times are GMT -4. The time now is 09:18 PM.

story-0
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-1
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-2
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


VIEW MORE
story-3
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-4
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-5
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-6
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-7
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-8
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-9
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE