94 speedo cable replaced, still fluctuates

[The_Epsicle]

I replaced the speedo cable on my 1994 Ranger and while it improved significantly I still have some needle bounce, it is worth noting the truck has had a tampered/false odometer title since 1995 when it had 15,000 miles, I greased the cable with white lithium grease before installation.

At 0-15mph the needle will point at zero, at 15mph the needle starts bouncing up to 10mph and back to 0mph, the needle stabilizes as 25mph at which point the needle is pointing at 30mph it continues this +5 behavior until 55mph when the needle starts bouncing between 55 and 65 and a loud groaning noise is present inside the cab coming from the speedometer, this groaning noise was present but louder before I replaced the cable. Adding to the weirdness, my odometer is reading perfectly, I measured it against my GPS(which I am using as a speedo) and the numbers matched up to the tenth of a mile.

I have my thoughts on what this could be but I want to hear your ideas before I poison the pool.

 

[RonD]

I think Ford used speed cup speedometer design.

Speedo cable is connected to a gear that drives the odometer so speed cup issue wouldn't effect it.

For speedometer part the cable turns a magnet inside the speed cup(the two are not touching), the speed cup is connected to the speedo gauge needle, as the magnet spins it pulls/rotates the speed cup in the direction of that spin, making the needle go up.
There is also a spring or a weight that prevents needle from jumping around and makes the upward and downward movement smooth.

So either spring or weight has failed or speed cup is touching magnet.

Just a guess

 

[The_Epsicle]

That was along my train of thought, it could be any combination of those things. Any clue how I could fix this myself? I couldn't find any replacement parts online unless I replace the entire cluster.

 

[RonD]

Pretty old now for parts, probably need to get a cluster.

Not sure of the fit but found 3 on ebay:

This one looks like it could be the one;
http://www.ebay.com/itm/94-Ford-Ran...1994|Model:Ranger&hash=item3a8e2ab793&vxp=mtr

http://www.ebay.com/itm/SPEEDOMETER...1994|Model:Ranger&hash=item4d134b865c&vxp=mtr

My '94 has this style:
http://www.ebay.com/itm/1993-94-RAN...1994|Model:Ranger&hash=item54149e551b&vxp=mtr

 

[fastpakr]

For what it's worth, you can use an Explorer cluster in a Ranger. Direct swap regardless of engine, and it gives you a tach.

 

[The_Epsicle]

I figured that would be the case, I know I can pick up one at a junkyard so I'll go that route. I'd ask how to change the milage on the odometer, but I'm assuming discussion on that subject is not allowed.

EDIT: Didn't see your post fastpakr, I have a tach on my cluster already.

 

[RonD]

I found this, about the only thing still out there on the old style speedometers, lol: http://obswww.unige.ch/~wildif/cars/docs/Smith-jaeger_speedo_repair.pdf

Odometer info as well

 

[fastpakr]

Ordinarily, the good news on a cluster swap would be that you can pop off the speedometer and use the existing one to keep the mileage the same. Kind of useless info here...

 

[The_Epsicle]

I found this, about the only thing still out there on the old style speedometers, lol: http://obswww.unige.ch/~wildif/cars/docs/Smith-jaeger_speedo_repair.pdf

Odometer info as well

I've downloaded it and will check it out later, looked pretty useful, thanks!

Ordinarily, the good news on a cluster swap would be that you can pop off the speedometer and use the existing one to keep the mileage the same. Kind of useless info here...

Man that would make things tons easier! Of course then I wouldn't have a problem to begin with... Don't worry I'll contact some guys I know that work at Ford and see if I can get my milage right.