Smith's Reverse Speedo problem and most gauges....

[donnieR32]

I realized very quickly that my speedometer doesn't work...actually I think the only gauges that are accurate are the tach and fuel pressure.

Anyways, I attempted to use GPS from my phone which claimed it was pinging between 7 and 11 satellites and in 3rd gear I was about 6 mph faster (on the dash) than what the phone claimed. Is this an issue that I can fix or is this something that will have to be handled in a shop?

[mickmate]

Yes you can send them in and have them calibrated. I have found they prefer a measured rolling number to a GPS measurement. Shoot me an e-mail address for the instructions if you want them.

[strictlypersonl]

First do a measured mile and check the accuracy of the odometer. If that's off, the change should be done by replacing the driven gear on the transmission end of the cable.

[elmariachi]

Originally Posted by strictlypersonl

First do a measured mile and check the accuracy of the odometer. If that's off, the change should be done by replacing the driven gear on the transmission end of the cable.

Great advice. Get the odometer synch'd first and then see what your speedo says using a high quality GPS. Too much latency in cell phone GPS technology.

[donnieR32]

Originally Posted by elmariachi

Great advice. Get the odometer synch'd first and then see what your speedo says using a high quality GPS. Too much latency in cell phone GPS technology.

Seeing that I don't have a high quality GPS I wonder if it would be more cost effective to just send them in.

[CHANMADD]

Most factory speedos read a little fast , designed in to keep us at or under the legal limit.
I have an app. Speedview, on my phone which I have found to be extremely accurate.

[elmariachi]

Originally Posted by donnieR32

Seeing that I don't have a high quality GPS I wonder if it would be more cost effective to just send them in.

You can install a calibrated speedometer in a car with the wrong speedo gear and it will still be wrong.

[donnieR32]

Originally Posted by elmariachi

You can install a calibrated speedometer in a car with the wrong speedo gear and it will still be wrong.

This is what I was thinking because it seems to be 6 mph faster in 3rd gear but like 9 mph faster in 4th....so maybe it is the speedo gear.

[strictlypersonl]

Originally Posted by elmariachi

You can install a calibrated speedometer in a car with the wrong speedo gear and it will still be wrong.

Most highways around here have mile markers along the way. Sometimes they're subtle: Just a post with a number.

[mickmate]

I agree to check it against a measured mile first. Even with the supposedly correct gear they can only come close. One tooth higher or lower will account for the reading difference you are seeing. The calibration instructions were sent to your e-mail.

[elmariachi]

Originally Posted by strictlypersonl

Sometimes they're subtle: Just a post with a number.

That's funny.

[donnieR32]

Originally Posted by CHANMADD

Most factory speedos read a little fast , designed in to keep us at or under the legal limit.
I have an app. Speedview, on my phone which I have found to be extremely accurate.

Is this serious? Why would anyone intentionally make a measuring instrument incorrect If I buy something I want it to tell me exactly what its meant to tell me. That's like buying a phone that hangs up mid-call to save you money.

I think I was using Speedview as well...I can't remember.

[elmariachi]

Originally Posted by donnieR32

Is this serious? Why would anyone intentionally make a measuring instrument incorrect If I buy something I want it to tell me exactly what its meant to tell me. That's like buying a phone that hangs up mid-call to save you money.

He might be serious but its not true. There is no underground collusion of forces trying to make sure all speedometers read wrong to slow us down. We might be headed in that direction, but I don't think we are there quite yet.

[DougD]

Originally Posted by strictlypersonl

Most highways around here have mile markers along the way. Sometimes they're subtle: Just a post with a number.

Don't assume that highway mile markers are placed at intervals of exactly one mile. Ever wonder what happens to the existing mile markers when the roadway is reconstructed, resulting in a longer or shorter route? Here's a hint - they don't dig up all the mile markers after the revised portion of the road and replace them. Take it from someone who has 35 years of road construction experience - the mile markers are not all a mile apart. They were never intended to be a precise measurement.

[vatdevil]

Remove the speedo cable from the trans and count the teeth on the driven gear. Try the next tooth count available. Not sure what trans you have but a Tremec replacement driven gear is around $20. Just replaced mine due to tire size change, very easy to do.

[donnieR32]

Originally Posted by vatdevil

Remove the speedo cable from the trans and count the teeth on the driven gear. Try the next tooth count available. Not sure what trans you have but a Tremec replacement driven gear is around $20. Just replaced mine due to tire size change, very easy to do.

Are these gears easily obtained at local automotive stores or will I have to order them online?

ETA:
To answer your question the trans is a Ford Toploader 4 Speed

[elmariachi]

Your local Ford dealer likely has a few of them (that's where I found mine for my TKO), if you can engage a knowledgeable parts counter person. Some reference here:

Ford Speedometer Gears for Automatic and Standard Transmission

[vatdevil]

Fortes Parts can supply.