B1B Keven Posted October 21, 2011 Report Posted October 21, 2011 I had my wife follow me in my '49 (her in my Hemi) to check the accuracy of my '49s speedo. At what I would consider max cruising speed (RPM's unknown as I don't have a tach) my speedo said 32 mph and the one in the Hemi said 45 mph. The truck has a late '50s 4 speed, 4:10 gears and 28 3/8" tall tires. It sounds to me like I've got the wrong speedo gear in the tranny. Thoughts? Quote
MBF Posted October 21, 2011 Report Posted October 21, 2011 Kevin-Have you pulled the screw in plug near where the cable connects to the back of the speedometer and put a few drops of oil on the wick? Is the cable lubed and free in the housing? I'd tend to agree w you that you've the wrong gear in the transmission. My 1 ton w a 3 spd, 3:89 rear cruises comfortably at an indicated 45, which is actually closer to 50 according to a chase vehicle. With your rear gears there should only be slighly slower. Someone on here awhile ago talked about ajusting the magnets within the speedo head to calibrate it. See if a search on speedo magnets gives you any ideas. Mike Quote
B1B Keven Posted October 21, 2011 Author Report Posted October 21, 2011 Yep, cleaned it up and added some oil to the wick and lubed the cable. Thanks Mike, I'll give the speedo magnets a 'search'. Quote
B1B Keven Posted October 21, 2011 Author Report Posted October 21, 2011 This is from a post made by Grey Beard. "In a few instances I have had to bend the revolving magnets closer to the drum that turns the needle." I'll give this a try. Quote
B1B Keven Posted October 21, 2011 Author Report Posted October 21, 2011 Well, that didn't work/help. Quote
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