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Discussion Starter #1
Long time, no post but i am checking out things almost daily. My speedometer fluctuates pretty irratic. I replaced the 17 tooth white gear at the end of the cable going into the t-case and that took care of it for a few weeks but now it is back to irratic. I have replaced this gear once about two years ago. I was told that it could be the large yellow 7 tooth speedo driven gear. At least that's what JBG calls it. My question is this; how hard is that to replace ? I searched this site and find a little info but never anything on replacement. What all is involved and what tools do I need ? If it matters, I can put a steady spin on the cable with my drill and things seem really smooth and quite so I am hoping that this is the problem.

Thanks for helping.

Frank
 

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Discussion Starter #2
Man, I just knew that someone had replaced this gear but I guess not on this forum ? Maybe this gear just doesn't go bad since no one responded ?

Thanks for helping.

Frank
 

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The speedo drive gear won't cause the speedo to be erratic unless it's damaged. You can look into the speedo hole in the tcase and see the drive gear. Watch it while you turn the driveshaft (on blocks, obviously) and see if there are any worn spots on the gear. If there aren't, that's not the problem.

Was your driven gear damaged? If not, that's not the problem either. If it was, or the drive gear is damaged, then you've got other problems because neither will just go bad out of the blue.

There should be virtually no bind in the speedo cable. If you spin the cable by hand at the tcase end, it should turn very easily and have NO catches or roughness. Pull the cable out from the speedo end and inspect it. Wipe it down with brake or electrical cleaner and lube it with graphite lubricant. Replace any damaged gears you found and see what happens. I worked on a lot of jumpy speedos when I was in the biz, most turned out to be dirty or damaged cables, I don't think I ever replaced a speedo gear while I was still working at the shop.
 

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Discussion Starter #4
Thanks for the help you two. This is the 2nd time I replaced the gear attached to the cable and yes, it spins relatively free by hand. When it gets jumpy, the gear looks to be concave in the center and when it is replaced, everything works OK. I was just curious about the large yellow gear and you all helped me out. And as far as panties, I think that you have me and you reversed !

Thanks again.

Frank
 
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