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| | | | Joined: Apr 2007 Posts: 11 New Guy | | New Guy Joined: Apr 2007 Posts: 11 | I replaced the original ring and pinion with a 3:55.1 in my 1952 GMC (248) from Patricks so I could drive highway speeds. I had to rebuild the trans after the syncro went out. I'm using the reducer gear that Patricks sold me to help with the speedometer. Now the speedometer is way off. The more I drive it for a day the worse it is. Any ideas what I can do besides replace my cluster package. The cluster package was new when I restored the truck.
Thanks
Larry Wilke
1952GMC 101 1959 Edsel Ranger 2DR and 1956 Dodge Lancer Custom Royal (in progress)
| | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Any good speedo shop should be able to adjust your speedo for you. Just determine how far off it is & let the shop know. If you don't have a speedo shop close by there are several that advertise in Hemmings Motor News.
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| | | | | Joined: Apr 2007 Posts: 11 New Guy | | New Guy Joined: Apr 2007 Posts: 11 | The difference changes the more I drive each day. Some times the speedo shows "0" until I shift to second gear.
Thanks
Larry
1952GMC 101 1959 Edsel Ranger 2DR and 1956 Dodge Lancer Custom Royal (in progress)
| | | | | Joined: Mar 2005 Posts: 1,029 Member | | Member Joined: Mar 2005 Posts: 1,029 | Has the speedometer ever worked since you installed the reducer gear? Is the reducer gear external to the tailhousing? If so, did you try running the speedo cable straight to the trans, bypassing the reducer? That would help verify that it isn't in the speedo head.
The speedometer gears in the tailhousing are often damaged when the tailhousing is attached to the transmission. | | | | | Joined: Apr 2007 Posts: 11 New Guy | | New Guy Joined: Apr 2007 Posts: 11 | the speedo has not been worked on since I installed the reducer gear. When I get back to Michigan I will try without. I'm in Arizona until the fisrt part of May.
Thanks
Larry
1952GMC 101 1959 Edsel Ranger 2DR and 1956 Dodge Lancer Custom Royal (in progress)
| | | | | Joined: Apr 2007 Posts: 11 New Guy | | New Guy Joined: Apr 2007 Posts: 11 | Should I try installing the reducing gear directly to the speedo and not the trans?
Thanks
Larry
1952GMC 101 1959 Edsel Ranger 2DR and 1956 Dodge Lancer Custom Royal (in progress)
| | | | | Joined: Mar 2005 Posts: 1,029 Member | | Member Joined: Mar 2005 Posts: 1,029 | That would be a question for Patricks, what did the instructions say? | | | | | Joined: Jul 2004 Posts: 427 Shop Shark | | Shop Shark Joined: Jul 2004 Posts: 427 | sounds to me that the reducer or trans gear is slipping.
Welcome to the bolt larry, visit often.
Wilbur | | | | | Joined: Mar 2007 Posts: 25 Apprentice | | Apprentice Joined: Mar 2007 Posts: 25 | I had the opposite happen. The speedo needle on my '54 would frequently fluctuate back and forth in a 20-30 mph range. I had a Patrick's 3:55 kit installed this week, along with the speedo gear set that he sells, and now the speedometer is spot-on and very stable. I had my wife pace me on the interstate yesterday and the 54 showed the identical speed as my 07, right up to 75 mph. (The 3:55 made a HUGE difference in the truck, as it will easily cruise at highway speeds, and the engine noise was noticeably reduced.) | | | | | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | The square hole in my speedo had rounded and the square end of the cable would slip, catch up and slip again. It was wild.
I enlarged the square cable end a bit with some epoxy and a file. I then made sure I didn't did screw it into the speedo too tightly. That can cause problems. It's now perfectly smooth.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: Jul 2005 Posts: 1,158 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 1,158 | Have you checked the cable/gauge with an electric drill? That'll tell you if your cable is bad or if your speedometer is shot. My money's on the reducer or the drive gear. Also, there's a speedometer place in Pontiac called Scott Speedometer . Not too sure where you are in Michigan, but they seem to be pretty good. Welcome aboard! | | |
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