2/79 H42 Speedometer Gear 5X18 (1 Viewer)

[Living in the Past]

I think the 5 is the shaft diameter or some. 18 is anyway the teeth amount. So no change to speedo/odometer reading.

On the chart earlier in this thread it shows two different part number for a 6 drive gear and lists teeth on the drive worm gear as six. The drive gear is a worm gear that fits on the output shaft of the transfer case. The drive and driven gear have to match otherwise the driven nylon gear will be short lived. This is why Toyota puts both gear teeth count on each part. I could be wrong but been researching this for a while to see what I can come with using bigger tires and 3:70 diffs.

 

[-MaTTi-]

The drive gear is a worm gear that fits on the output shaft of the transfer case. The drive and driven gear have to match otherwise the driven nylon gear will be short lived. This is why Toyota puts both gear teeth count on each part.

Well, mine BJ42 had 6x16 gear. I found that the output shaft is rated for 15 to 17:

For some reason there was only available 16 and 17 gears:

But I found 6x15 gear from BJ40:

But the transfer gear is meant for 16 to 18 teeth gears in BJ40:

However the 15 teeth gear works in my BJ42, I don’t see a reason why not.

 

[-MaTTi-]

The gear ratio on my speedometer wheel is 5x18 (18 teeth).
What am I missing?

Could it be from some other model? Hiace? 33482-39085

 

[OPMACHINE]

@-MaTTi- I am pretty sure the one I have is mis-stamped. I have a new 6X18 on order. I will post the comparison

 

[Living in the Past]

Well, mine BJ42 had 6x16 gear. I found that the output shaft is rated for 15 to 17:
View attachment 3265800

For some reason there was only available 16 and 17 gears:
View attachment 3265801

But I found 6x15 gear from BJ40:
View attachment 3265802

But the transfer gear is meant for 16 to 18 teeth gears in BJ40:
View attachment 3265807

However the 15 teeth gear works in my BJ42, I don’t see a reason why not.
View attachment 3265817

Do you have the fifteen tooth driven gear? Thought those became NLA in the last couple of years.

@-MaTTi- I am pretty sure the one I have is mis-stamped. I have a new 6X18 on order. I will post the comparison

Was your speedometer not working or just trying to correct how far off it reads? The 6X18 is for a stock FJ40 in the US market with 4.11:1 diffs. Believe stock tires were around 29" tall. To increase the reading at the speedometer you was to decrease the ratio between the drive and drive gear. The closer they are the faster the speedometer will read.

 

[OPMACHINE]

I am generally going thru my 79 FJ40 and replacing broken and worn parts. I have the e-brake and speedometer housing off. I put in a Valley Hybrids double seal housing and new brake components. The driven gear is functional but shows wear. I have been looking to replace it amongst other things. The current driven gear is stamped 5x18 which does not exist. So I have been trying to figure out exactly what I have. My best guess is that the current 5x18 driven gear was mist- stamped. If I was smarter I would have replaced the drive gear so I could correct with a 6x16. But the everything is back together so that will be a project for next time.