P0500 Jshift t case swap now no MPH

Hi all! New member to the group. Happy to be here.
I took a J shift tcase from a 2000 4Runner and swapped it into my 98 Tacoma. The 4Runner case had a cap where the speedo would go. I removed the cap and installed my speedo, the one from my original tcase. I have no speedometer on my dash and my check engine is on with the PO500. I took the speed sensor out, spun it by hand and it showed MPH. I am confused as to why this is happening. The gear “worm gear”? is on the speed sensor. I even swapped the sensor out with another for shits and giggles, but nothing.

Any help would be greatly appreciated!! Thank you all.

Also sorry if I posted this in the wrongspot, should I have started a new one?

 

Since it wasn't used on the original application the transfer case may not have the drive gear installed for the speedometer.

 

The drive gear for the speedo gear is not there. The 2000 transfer case would be electric speedo not mechanical.

The lack of speedo is the cause of the check engine light.

There may be some kind of adapter to go from elect speedo (TC) to mechanical speedo (truck). I'm not sure, I've never seen that.

I have seen an adapter to go from mechanical to electric... I had to do this with a 96 transfercase in an 02 truck.

 

I might run into this also Matt. Supposedly the tcase I have here is off a 95 taco.

@Clark530, welcome to TacomaWorld. I know I bookmarked a few pages on this, will do some digging and add what I can find.

 

Thank you guys. Those were my thoughts exactly too. But I do see the drive gear in the TC, and it looks to be the same as the drive gear that was in the original case. That’s what has me stumped.

 

Pics?

 

@Clark530, see this post.

https://www.tacomaworld.com/threads...4-conversion-parts-list.751045/#post-26752009

Scroll down and this is what you're looking for. Hit up @yotadude520 if you need more info.

 

You'll run in to the same thing I did. You're speedo is electronic. You'll need a mechanical adapter. Super easy, just thread it in and plug in from the truck.

You'll need to splice in some wire too. The speedo wire won't reach back to the transfer case. It'll be 12 inches of added wire, or so.

You'll need one of these.
https://trail-gear.com/drivetrain/speedometer-adapter-mechanical-to-electrical-vss.html

 

Original tcase from 98 Tacoma

 

J shift tcase from 2000 4Runner

 

Well that makes no sense then.

Cause that gear should be spinning with the drive shaft. I wonder if the depth your speedo gear from your truck is different, and not going all the way in to engage the truck gear in to the gear in the TC.

 

This is why I am so beyond confused lol I will get exact measurements tomorrow. But I’ve looked at it in detail and it appears to mount up and be at the same depth as the original
Could a guy buy that part you’ve gave the link to (thanks for that!) And install it somewhere on the tcase to get MPH? In other words where does that adapter part go? It doesn’t go in the hole where the gear driven sensor goes right?

 

The adapter threads I'm the TC where the speedo gear is. All the adapter does is change the mechanical to send pulses to the electrical speedo on the truck. That adapter would do opposite of what it sounds like you need.

 

Thank you. That’s kinda what I was thinking. Like you said it has to be that the gears are just not aligning properly. Because when I spin it by hand I get a response. I am just not seeing why it doesn’t align properly. I even thought the gears might be facing different direction, but it appears they go the same way.

 

I do know that she'll on the back of the Tcase (that the output shaft passes through) that holds that output seal (I believe the shell I'm talking about has 6 bolts holding it on the Tcase)... you can buy that shell as an assembly with the seal in it.

The shell I'm talking about is what holds the VSS gear. I wonder if that shell is different between mechanical and electronic speedo, causing the gear to be in a different spot.

That is just a guess.

 

First off thanks for all the help, and so quick!

So a few interesting finds..
The worm gear that was on the original tcase was a little bit thicker walled. Making the OD wider. I didn’t mic it but it measured about 1/16” bigger OD.the one on the left is the thicker one. Which seemed promising.
The next discovery seemed to be even more the issue.
There was a little ball type retainer in the side of the output shaft (in the original), and the worm gear has a little slot that goes over the steel ball. The shaft on the tcase from the 4Runner did not have the little steel ball retainer. Allowing the shaft to spin but the worm gear would not because the ball wasn’t there as the “key way” if you will. Changed the worm gear out for the slightly larger one, set the steel ball, and reassembled.
AND BAM IVE GOT MPH!!
Thanks for all the help you guys, it has been greatly appreciated!!!

 

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Super interesting, how has this held up? I'm wondering if I'm about to encounter this, I just picked up a '98 4Runner j-shift for my '03 Tacoma. I'm assuming the 4Runner tcase had the recess for the steel ball, it just wasn't there?

 

Just opened up the plug on mine and the worm gear *appears* to be moving with the shaft even with some added resistance, so I'm hoping it'll be ok