I'm still a bit lost on all this.....

I'm pretty sure I'm just gonna rebuild the tranny I have....or maybe get one of Marlins rebuilds. The question now is what to do about the T-case.

The way I understand this....I have 2 options for a gear driven t-case 1) get one out of a 4-cyl turbo truck that has the 23-spline input shaft......can someone tell me what years that truck was available in?.

OR

Get a standard 4-cyl t-case and rebuild it with the Marlin V6 conversion parts?

Is that correct? And can someone tell me more about option 2...what parts do I need?

You will need to get an adapter from Marlin or Inchworm to mate to the back of your transmission to run a gear driven transfer case. These adapters are made to run a 23 spline transfer case, which was only found in the 86 an 87 turbo pickups. They are as rare as hen's teeth. You can buy the 23 spline input from Marlin or Inchworm and convert a 21 spline case, but it is only a little more money to just buy 23 spline low range gears (4, 4.7, or 5) from either of the above vendors.

Have you tried the cheep fix yet???

Your tranny may be perfectly fine and last you another 100k miles. Before you go dumping big cash into a tranny rebuild you don't need try the easy/cheep solution first.

Here used 4-cyl T-cases are cheep. So maybe an adapter is the way to go.

I may go the "cheap fix" route on the tranny. After looking into things, I'm pretty sure it is just the shifter bushing. But, I also like reliability and re-building or replacing the whole thing pretty much puts any concern about bearings to rest.......just have to see how much $$$ is in the slush fund when I start wanting to tinker with things again.

Another t-case question.....I've come across an 87 4-cyl Turbo 4Runner with an automatic tranny. Does that t-case have the 23-spline input on it?

And thanks for the answer on converting a 21-spline to a 23-spline. I would defintiely go with the crawler gear conversion parts. I saw those on Marlins website and didn't know if I could just put them into a 21-spline case and convert it.

As a wise man once said, if it ain't broke, don't fix it. When the bearings go you generally will have gradual notice.

Of course, there is the alternate saying, if it ain't broke fix it till it is...
Nope, sorry. Whole different animal.

Yep, in Toyota's infinite wisdom the only difference is the spline count and engagement area diameter. Even the bearings are identical. If you go 4.7 or higher, you will need to hog out a bit of the aluminum case interior but it's simple with a die grinder, following the instructions.

How much of an advantage would 4.70....or a dual case be for me. I've got the 3.4L (and considering putting a blower on too)...so, power isn't my issue. And, I've never been in a situation where I couldn't go slow enough. Would it really be worth putting 4.70 gears or getting a dual case?

If you haven't been in a situation where you need more gearing than there really isn't an advantage to the 4.7 gears.

In fact, you won't like the fact that your snow-bashing speed is slower. However, I suggest you spend some time wheeling with Rising Sun 4x4 and discover the joys of needing lower gears! Then put on dual cases for the best of both worlds.

Hmmm. Didn't I say Scalded Dog would cost you a lot of $$$? Oops.

So now *I'm* the problem... <img src="/forums/images/graemlins/smile.gif" alt="" /> Well, while I'm spending your money...

If you do 4.70's you'll be very happy, except on those really easy sections where you'll have to run in 4th gear to keep up with your stock geared friends. If you go 4.70's, then make that the rear case of a dual case setup with stock gears in the front, you'll be happy in all situations, except the one where you have to explain what you spent to your wife. <img src="/forums/images/graemlins/shiner.gif" alt="" />

Mark

I've got that one covered......no wife.