Speedo gear red and brown? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum

Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 09-24-2007, 07:18 PM
redlightning's Avatar
Last photo:
Join Date: Aug 2004
Location: TN
Age: 52
Posts: 1,084
Wiki Edits: 0

Thanks: 3
Thanked 11 Times in 5 Posts
Speedo gear red and brown?

I just bought an 80 camaro that was an unfinished project.I got it running but the speedo is not working.
I have it up on jack stands.The speedo gear is not turning.It is brown and I can see the gear inside is red.
Should these two colors match up enough to turn the speedo gear.
The reason I ask is the guy I got it from had the trans "rebuilt".I found the gear in some bolts he had given me for the car.So I don,t even know if it is close to the right gear.
It is a th350 with 3.55 gears(he had them installed also).

On a side not here.I have not owned a chevy in over 20 years.I got a good deal on this one.Rebuilt 350 041 heads,flat top pistons,mild cam.It,s a fun car.It may wind up on ebay so I can finish my 56 ford but I might just keep it.

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 09-24-2007, 10:33 PM
Last photo:
Join Date: May 2003
Location: Shreveport LA
Age: 67
Posts: 5,106
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Assuming your brown gear is ~3/4" in diameter, the red gear has 10 teeth, and the brown one has 18. What you have is a 1.8:1 ratio, which would be used with some serious highway gears, or some seriously large tires.

With 3.55 gears, you'd need 39.8" tires to make the speedo right. Got clearance?

With 26" tires, you'd need 2.32 gears to make it right. No fun in my book.

Take your tire diameter and rear end ratio to www.novaresource.org/speedo.htm and use the formula to calculate what speedo gear ratio you need. Then use the chart to find what gear combos will give you the ratio closest to that. Gears are cheap at the Chevy place, or you can get them online.

It's possible that the drive gear (the red one) is not firmly attached to the tailshaft itself. There's a small metal clip that holds the gear to the shaft, and if it's broken, the shaft can slip inside the gear, and the brown gear won't turn like it should.

Last edited by jimfulco; 09-24-2007 at 10:42 PM.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-26-2007, 10:29 AM
redlightning's Avatar
Last photo:
Join Date: Aug 2004
Location: TN
Age: 52
Posts: 1,084
Wiki Edits: 0

Thanks: 3
Thanked 11 Times in 5 Posts
FIXED. I pulled the gear out of the trans and took it to a local trans shop and told them what the problem was.I showed the gear to one of the older guys there and he said," That looks like a Buick gear".He gave me one for chevy.I got it in and it works.

Jimfulco,Thanks for the link.
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
changing my spedo gear to get right after rear end swap montea Transmission - Rearend 4 10-04-2005 03:33 PM
the brown wire comin from the white clip on a chevy blazer altenator?? badk5 Engine 12 06-27-2005 08:23 PM
Camaro VATS ignition and column RockinLocks4u Electrical 9 02-03-2005 09:34 PM

All times are GMT -6. The time now is 09:31 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.