Speedo questions (1 Viewer)

[IDave]

I've recently discovered that my speedometer readings are off. I have a new (1 y/o) stock speedometer on stock size (29 inch) tires. The cable was replacement but I think aftermarket. I have checked my actual speeds by several methods: the radar things they set around town (Speed Limit/Your Speed), following traffic/my wife's car at a known speed, and by GPS on the interstate, so I am fairly confident of the numbers. What happens is: speedo reading, 25 mph, actual speed 25 dead on. Speedo reading 40, actual speed 35. Speedo reading 50, actual 45. Speedo 80, actual 73. At 35 mph speedo reading there is a vacillation of the needle that ranges from 30 to 40 mph on the gauge. It goes away above and below.

The cable seems about the right length but could be a titch longer comfortably, I think. I have looked at the plastic gear in the transfer/ebrake housing, and it looks pretty much ok (like no broken teeth), but ?

Anyone out there who could point me in the right direction as to what I might to do next? I could get by, obviously, but I'd like it to be accurate.

 

[dd113]

Do you have the wierd little speed marker box? Not at all sure what it does but it is line with the speedo cable on some years. I would pull the cable out and lube it. There is a tech link here, I think, on how to rebuild the speedo. I bet if you clean and lube it will work better. One thing here, we are assuming that they were accurate when produced. I have no idea if that is true. How about a poll?

 

[IDave]

Thanks, Dave. I'll lube the cable.

No marker box on my year.