Speedometer mod

[LAMBCRUSHER]

My speedometer is noisy/ dying; odometer hasn’t budged in a decade, SO.....


Fj62 top, fj55 bottom-77 vintage...

Fj55 left; fj62 right. Note; they both have a speed sender; both send the same ground signal... the harness is different in one way...

The fj62 has screws securing ring terminals to metal tabs that screw to the speed sensor terminal...

The55 has spade terminals screwed to the sensor terminals...

So unscrew the fj62 speed sensor wires and leave the screws out, unscrew the trip odometer reset plunger, and the 3 face plate screws...

Then unscrew the 2 larger screws on the rear of the housing and dump the gauge out in your hand. Pull the face plate screws and gauge retaining screws from the 55 meter and dump it out too...

 

[LAMBCRUSHER]

55 left; 62 right note how similar the plastic instrument housings are...

Also note the metal frames that the 62s speed sensor wires screw to...the bottom one- on the left side- needs a trim; the top one comes off...

Here are the screws for the speed sensor wires...3 of the on the 62... take the out... also take out the screw at the bottom end of that wire, remove the wire and replace the screw at the base of the housing...

Take these 2 screws out and pull out the speed sensors...

 

[LAMBCRUSHER]

55 left...

Greasy...

Cleaner...

Fj55 spade term speed sensor in fj62 guts...

This bit needs a trim... little by little... till it fits and the trip odo reset plunger deist bind...

 

[LAMBCRUSHER]

About halfway done... you trim the corners too... as far as you can with the lineman’s... I cut more than what is shown here. Some gentle bending upward on the plunger frame helps. Trim the fit into housing.. you’ll think you got it but you need to make sure the plunger isn’t getting pushed up. It fits like a glove when you get enough of that frame relieved...

Next thing is the plate. The fj62 plate has bumped out scre holes and the hole for the plunger...

To fit in the fj55 bezel, the bumps need to smooth... don’t try to use a cutting tool... use a grinding, sanding or sawing tool... the 55 plate is glass...

Pull the fj55 plate and rubber grommet out of the bezel. Be careful, it is glued in and is tight. The glass is thin. Don’t go to the hospital cause you broke the glass getting it out and sliced your hand open. I did not do that; just fair warning...

 

[LAMBCRUSHER]

The fj62 guts in the fj55 house. It is biased a tad high- I will relieve the upper side of the slot to gain more clearance on the spades...

I used the fj55 trim ring...you could trim and use the fj62 trim ring if you prefer...

Here it is mocking us... I need to drill the retaining ring screw holes just a tiny bit lower on their face of the ring as the fj62 plate is thicker and pushes the retaining ring out by about .005”

 

[LAMBCRUSHER]

I have a new cable en route and will stick this thing in this week end...

 

[Ol Yeller]

Sweet! Great write up.

 

[scrapdaddy]

Good tech!

 

[brisveganbj42]

nicely done, cheers for sharing!

 

[bobm]

U gonna hit the 110

 

[Docktormike]

can you do mine?

 

[61twpw]

Great write up. Way to upgrade and problem solve.

 

[LAMBCRUSHER]

I’m gunna find out if I can do 110 tomorrow...@docktormike, if you supply the gauges, I’ll swap the guts and make any mods needed to the instrument and housing for a sixer of ballast point delivered to the pig party

 

[LAMBCRUSHER]

I was able to simply bend the housing away from the terminals to gain clearance there

Here you can see the amount of clearance needed to trim off the trip odo frame

 

[LAMBCRUSHER]

Bend the hat shaped light diffusers as far toward the outside of the housing as it will go, and roll the flat flaps all the way around till they point toward the back, but are tightly curled over the edge.( no pic of that/ you can cut them out or skip this entirely) this is to gain more back lighting and is totally optional- as is the speed switch for guys with engine swaps and desmogs

 

[LAMBCRUSHER]

The pesky pin that makes it hard to slide the odometer shaft to the side so you can remove it without breaking the plastic instrument housing... not that anyone would do anything with it, of course, just to look at it in glorious awe...

And a wider angle view for context...

The shaft can’t come out and the odometer cannot be altered because that pin locates the shaft and prevents it from sliding (left) and the becoming accessible without causing irreversible harm to the gauge... interesting stuff, that... (pull)...

 

[LAMBCRUSHER]

(Left)

 

[LAMBCRUSHER]

But this thread is not about how a speedometer and odometer work; it is about how to put a better one in place for keeping track of you trail rigs fuel consumption... innit, then?

 

[LAMBCRUSHER]

Before

After

 

[LAMBCRUSHER]

Did not get to 110. Did get to 60(dial), but gps ap said 58.5. It said I was reading 1 over actual on the dial for every 10 mph up to 60.
It did say the trip odometer was dead nucking futs on the money. Between that, and the silent telemetry, I must say, this seems to have been a very worthy mod... hope that helps!