Hello everyone! First time posting, long time lurker.

I recently finished a transmission and transfer case swap on my 91 4Runner. I took out the old G58 tranny with what I believe is a VF2A chain driven transfer case for the W56 and a RF1A. Fairly straightforward swap but as I found out not everything is interchangeable.

The speed sensor and the 4WD indicator switch for the transfer case are not the correct size to swap over from the VF2A to the RF1A. I went to a yard and found a speed sensor that fit and mated to the case and the cable (I have a mechanically driven speedometer cable) off of an only first gen pickup. But I still have no readings on the speedometer when driving.


Its a 16 tooth gear, is this correct or do I need a different one and if so, a part number would be an awesome addition. Or is it possible I mated the cable incorrectly and there’s a trick to installing these that I’m not aware of?

Second question is if anyone knows the part number for the 4WD indicator switch? I’ve found a few on eBay that I think are the right ones. But when I asked for fitment verification on an RF1A they only respond by asking for my vin number and tell me they can’t verify the part will work since the original transfer case isn’t in my vehicle…

Thanks everyone, I’ll make sure to check in to provide any more information to help solve my problem!

 

My RF1A transfer has a 6 tooth worm gear inside.

This 6 tooth worm gear will mate with a 18, 19 or 20 speedo gear. A 16 tooth gear probably has a too small diameter to mate with the worm gear.

What's your differential ratio, and what size tire do you have? I can then tell you what speedo gear and part number to get...

The 4wd switch should just be an on/off switch, so if it fits a RF1A, it should work. Look up the part with the toyota epc database

https://toyota-usa.epc-data.com/

 

Thanks for the parts link emsvitil!

I have a 4.10 ratio and my tires are 31s.

If there’s a chart online for the tooth count to use depending on the ratio and tire size could you provide the link for it?

That way when I regear and go up in tire size I don’t have to post a new thread.

 

No chart, I made a spreadsheet.

With 4.10 and 31s you need a 17 tooth gear.

30 years ago (or more) when I got 31s for my 225/75s, I did the math and figured out I'd need a 17 tooth gear to replace the stock 18.

The dealer found a 17 part number, and it worked for a couple of months, then it started randomly not working.

I took the drive out and found it had worn the teeth in the middle just a little. But the little bit was just enough for the gear to no longer make contact with the worm gear inside the transfer.

I ended up modifying the gear by superglueing cutup tie-wraps to the teeth so the gear got a larger diameter. Amazingly enough it still works.............

Here's the part numbers for the various gears and the sleeve they fit into:

Teeth gear sleeve
18 33482-39135 33404-35010 for all
19 33482-39025
20 33482-39045


Assuming you came with 4.10 and stock 225/75 tires.

The RF1A came with 6 tooth worm gear and 18 tooth speedo gear.

When getting larger tires, you need less teeth on the speedo gear.

When getting higher ratio diff, you need more teeth on speedo gear.


So 18 teeth * (old tire diameter / new tire diameter) * (new diff ratio / old diff ratio) = new teeth for speedo gear..........

Look up actual tire diameter on tirerack.com Stock 225/75 is about 28.3 and 31s are usually 30.5, 33s =32.5.

You should come up with a tooth count of 18 with 4.56 and 31, 20 with 4.88 and 31, 19 with 4.88 and 33.

 

Used your link and part number for the gear, also picked up the 4WD switch on the same sight. Everything works now, thanks so much for the help emsvitil!

 

I know this is a dead thread, but if youre still around..Where did you get the "transfer indicator switch?" I've been looking all over for one.