Eating spedo gears

[the_dingman]

Background: I replaced my transmission about 2 years and 10k miles ago with one off an '88 junker I bought for parts. We kept the speedometer gear off the original transmission, in case there was a difference in gauges.

Since replacing my transmission, I've had to replace the speedometer gear twice, and now it required a 4th one! I can't figure out what is causing the gears to wear! They start to cup in the middle, clearly they are getting worn out somehow.

I have lubed my cable, and it doesn't seem to stick. As soon as I replace the gear, it works perfectly for 3k-4k miles.

When is starts to go, it becomes jumpy, then for a while only works while slowing down, especially when engine breaking.

Any ideas? I'd like to stop replacing the damn thing!

Thanks in advance.

 

[cometobanks]

Hey Ding, I dont know if it will help but I saw this,

Speedometer Gear problems... [Archive] - FSB Forums

 

[the_dingman]

Good thoughts. Nothing else is wrong with my T-Case, so I was hoping it wasn't an issue like that, but it's looking like it is. I'll do some more research on it.

Thanks for the help!

 

[Tkelly5]

Speedo Nylon Gear Pix - take a look and comment please

91 4Runner, 2WD, auto, 6cl, 3.0L , 3VZE , A240 transmission .
Had a used transmission placed on truck 500 miles ago, speedo quit. Heard some clicking noises down below when speedo quit. Speedo cable was really loose in the screw in housing . I took unit part out of the tranny, put a drill in reverse on the nylon worm gear, speedo works fine no binding. Put back in truck up on stand, RPM at 3000, no movement.

Here is the gear-- just to verify, this looks cupped/eaten. Am I correct?

If so, what web site can I get a replacement on? I went to village Toyota.com having a hard time locating.. Thanks...