95 chev 2500 tach and speedometer

My trucks speed and tachometer come and go.I have replaced the instrument cluster but this did not help.sometimes i start the truck and it works and sometimes it doesn't......someone please help
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Roger, I had this issue on my truck. It turned out to be the speed sensor on the tranny.
Good luck...
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<07_GMC> wrote in message wrote:

For the tach as well as the speedo?
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wrote:

No, just the speedo. I misread your post - sorry about that... Since the problem's intermittant, I would wait till it's acting up again, and have someone jiggle the main harness at the firewall and see if it makes anything in the cluster work. I'm not exactly sure if the tach is tied to the speedo by anything or not, but since it's intermittant, I'd first assume that there's a loose connection on something, somewhere. Not much of a help, I know, but maybe it'll get you pointed in the right direction.
Good luck
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