2WD to 4WD conversion

Better to ask in the regional forum.

 

if you're going to do such a serious mod, might as well look into the FJ cruiser transfer case!

 

Would be awesome of there was someone down south around Texas to help me with this conversion. I'm talking with Rock Solid Toys about working with their shop on this now but would be much more affordable to pay someone more local.

 

Just a note about my perspective:
I'll be moving to MT ina few months and need the 4x4 capabilities, but refuse to give up my prerunner. Mechanically, I refuse to touch an engine aside from oil changes, but I will tear apart just about anything else on the truck if I have to. Admittedly If I had to do anything with the transmission other than drain, remove, replace, and fill, I wouldn't touch that either. From the looks of it, this is a large, but very feasible job. This is a compilation of some info and opinions I gathered while researching before I made my decision. I hope this helps.

I was in a pretty similar spot as yourself, but to keep it brief, here are some things you should have a look at or know.
There are two ways your conversion will likely go, fast and expensive, or slow and more affordable. Some people were able to do this very affordably by collecting parts over the course of months or even years looking for craigslist or TW deals. Personally, my truck is a DD and I don't have the space to let it sit while I work on it for an extended period of time. I know myself, even if I had all of the parts at once (which would probably be impossible) it would take a very long time to get it done and done right.

When it comes to those saying that it isn't worth it unless you SAS, I don't know what perspective they are coming from, but from a monetary aspect, it makes no sense. You could save a couple hundred $ by foregoing a front diff and the associated parts and CVs at the cost of at least a couple thousand to get a decent axle, the suspension, the links, brackets, and hardware necessary to get that done. However, a few things to look into might be using an FJ T-case and maybe a crawl box since your changing driveshaft lengths and possibly cutting up the floor a little bit anyways.

As for some reading material, here's a nice list including articles from Wyatt at RST as well as a few others that have gone through the conversion process:
RST: https://www.rocksolidtoys.com/single-post/2018/05/16/2WD-to-4WD-Conversion-for-2005-to-2015-Tacoma
https://www.rocksolidtoys.com/single-post/2017/08/25/05-Tacoma-IFS-T-case-swap-wiring-instructions
More from Wyatt:
https://tctmagazine.net/december-2012/2wd-to-4wd-conversion-part-1
https://tctmagazine.net/march-2013/2wd-to-4wd-conversion-part-2?
TW Members:
Has a parts list-https://www.tacomaworld.com/threads/06-prerunner-conversion-to-4x4.394107/
Included very neat manual ADD conversion-https://www.tacomaworld.com/threads/lucky-07-prerunner-to-4x4-conversion.311339/
FJ Tube ADD Delete-https://www.tacomaworld.com/threads/how-to-deleting-add-system.427258/
Some insight into what I believe the hardest part would be, removing/replacing the transmission:
https://www.youtube.com/watch?v=oZDSjlxl2Q4

As for a short summary of the parts you will need, here's off the top of my head:
A750F Transmission
FJ Transfer case, make sure it's not an AWD one or else you'll have a whole other conversion on your hands
Get your rear driveshaft shortened
Obtain stock front driveshaft and have it lengthened
Modify transmission cross member (or buy custom one from RST)
Wiring harness so the dash works like stock (custom from RST)
Front diff +CVs+misc hardware
4x4 Hubs & dust covers
Lots and lots of small parts you likely won't be able to foresee.

This is all food for thought, but there is plenty of info out there to be found regarding the conversion. Personally, unless you are emotionally or very financially invested in your truck, it will be way easier to just trade it in and swap the compatible parts. For me, it's my first truck, my first (non-beater) car, and I plan on keeping it forever. I ended up going to RST for a few reasons. I don't have the time and space to let the truck sit while I work on it. After pricing everything out, the price difference between having RST do it and doing it myself didn't warrant forgoing a warranty and having an experienced mechanic who practically wrote the book on conversions for the Tacoma do the work.

TLDR: If you don't plan on keeping your truck until its ran into the ground, just trade it in. If you are short on time and space, have someone else experienced do it for you. I would love nothing more than to do it myself and gain all the experience there is to be had doing it, but for me it just didn't make sense realistically or financially. Take from this what you will, but this is not a project for the light hearted. If we were talking first gens, it'd be a whole other story.

 

We share some things in common, one being that I will not give up my truck so figured I might as well keep investing in it. I’ve spoken with RST about the conversion as well. I’m slowly piecing the parts together and an FK transfer case as well. I’ll definitely keep everyone posted with pix of what happens and hopefully this doesn’t turn into a big train wreck lol.

 

Find cheeper parts from other models that are comparable.
I found a junkyard that allowed me to remove the 4wd computer and wiring/plugs. So I made an awd beast!
I’ve got all the normal modes but also have a center diff.


As for a daily driver, you can do the conversion in 2 major parts.
First wound be new 4x4 hubs, cv front diff.
Second is tranny, tcase, modifying the crossmember. Installing the front driveshaft and getting the rear modified to the correct length.

 

Definitely enjoy converting my.

 

I converted my Prerunner to 4x4 and used the FJ manual transfer case a few years ago. Also used the Inchworm trans adapter so i wouldn't have to get a 4x4 transmission. All you do is remove the tailshaft housing from the 4x2 trans, cut off about 5 inches from the tailshaft, install the adapter and 4x4 tailshaft housing and install transfer case. No need to remove the transmission for any of it. Only downside is you need to shorten the rear DS about 2 inches and lengthen the front DS the same. The adapter moves the transfer case back some from the stock location. I was going with a 1pc rear ds anyways so it didnt matter to me.

 

When I was doing research for mine I looked into that, but unfortunately they dont make those adapter plates anymore. If he were to go that route, itd have to be a custom project.

 

yeah somebody asked me where I bought it and checked the website but they're extinct now.