‘64 Speedometer Woes
Thread Starter
Racer
Joined: Aug 2014
Posts: 414
Likes: 53
‘64 Speedometer Woes
A customer brings me a ‘64 with clutch problems and hung in reverse. I get everything apart, check the transmission by visually taking the side cover off and everything looks great, fresh rebuild. I put a new clutch, pressure plate, and throw out bearing in, align shifter, reinstall everything and go for a ride. Notice on the ride that the speedometer is about 10 MPH off!. I had my son to check it with his phone app. And it also confirms it. Bring it back to the shop, check the speedometer gear in the transmission and it is a green gear with 22 teeth which indicates a 3:70 rear end. Check the code on the rear end and it says it is a 3:70. Did the tire/drive shaft count and that confirms it is a 3;70.
Tried playing around with some different speedometer gears that I had but it did not make any difference made matter worst, tried a 19, and 21. A 24 would not fit. It must be a mismatch in the transmission tail housing correct. Any ideas, want to get it corrected.
The gauge cluster is fresh looking and there is not bounce in the speedometer hand. Looking for suggestions,
Tried playing around with some different speedometer gears that I had but it did not make any difference made matter worst, tried a 19, and 21. A 24 would not fit. It must be a mismatch in the transmission tail housing correct. Any ideas, want to get it corrected.
The gauge cluster is fresh looking and there is not bounce in the speedometer hand. Looking for suggestions,
Drifting
Joined: Aug 2004
Posts: 1,294
Likes: 295
From: Galveston & Belton Texas
edit: I assume the poster knew that the speedo was accurate before he started? If so, I would agree with you. If not, I think I am on the mark.
Last edited by tgtexas02; May 17, 2020 at 08:41 PM.
Le Mans Master
Joined: Feb 2008
Posts: 5,214
Likes: 447
From: NJ Hockey beer league
You have tried different gears with no change, the cluster appears to have been gone over recently, so my suggestion is to pull the speedo cable and directly connect a drill (running in reverse) and test it. I suspect when you remove the speedo cable, you will find a bunch of grease that has migrated up the cable (because it was over lubed when installed) and has fouled the speedo cup. If that's the case, you will have to remove the cluster and re service the speedo head to fix it.
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Thread Starter
Racer
Joined: Aug 2014
Posts: 414
Likes: 53
Speedometer Woes update..... I pulled the cluster and drove over to D&M Restorations in Greenville, SC. They did a quick check and just as I thought it was 8 MPH too slow. I had them to rebuild the Speedometer and Tachometer heads, the rest of the gauges checked out fine. I reinstall, test drove, all is well. Nice to see smooth Speedometer and Tachometer hands. D&M turned this around for me in a day. Dropped it off on Monday around lunchtime, picked it up on Tuesday afternoon.
Drifting
Joined: Aug 2004
Posts: 1,294
Likes: 295
From: Galveston & Belton Texas
Speedometer Woes update..... I pulled the cluster and drove over to D&M Restorations in Greenville, SC. They did a quick check and just as I thought it was 8 MPH too slow. I had them to rebuild the Speedometer and Tachometer heads, the rest of the gauges checked out fine. I reinstall, test drove, all is well. Nice to see smooth Speedometer and Tachometer hands. D&M turned this around for me in a day. Dropped it off on Monday around lunchtime, picked it up on Tuesday afternoon.