Corvette Forum : DigitalCorvettes.com Corvette Forums banner

1 - 2 of 2 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
After having a number of issues with the speedo in my 1969 corvette coupe, I finally replaced everything. I started with a 21T red gear, a new bullet for the gear, new cable and housing, and a used speedometer out of a 1971, with 58,000 miles on it. When finished, it worked great for about a month, then just stopped. I went back through and rechecked everything from the gear to the speedo head, and everything was fine. I then pulled the speedo head again and found that the problem was inside. After disassembly, I found a lot of heavy grease around the gears and a chunk of crud lodged into the drive gear, which had jammed it up and stopped it from turning. I took it apart and cleaned everything out, and reassembled it with white lithium grease for lubricant. I did not change anything in the speedo drive assembly, I just cleaned and reassembled. Now, my speedo is reading 15mph slow. It is smooth and consistant, but reads 15mph slow at all speeds. Do I need a new gear at the transmission? I am very confused as to why this is happening when I did not change any parts. Any Ideas or advice would be greatly appreciated. BVette1000
 

·
Registered
Joined
·
905 Posts
If you go to Bowtie Overdrive's website, there is a section for calculating speedo gears. You put in your rear tire size, rear end ratio, and type of transmission and it will tell you what color and how many teeth the gears should be. Worked perfectly with my 77 when I switched to 3.70 gears and a 7--R-4 tranny. Art
 
1 - 2 of 2 Posts
Top