So, I have a 2wd 2.7L auto '99 ultra-base model... based on the Toyota Options page elsewhere on this site I think I have the base model w/ Upgrade Value Package #1.

I want 4wd.

My wife and I love this rig (can I call it that, even though it's only 2wd?) and we don't want to trade it. I'd like to swap parts from a wrecked Taco or 4Runner of similar vintage; ideally I'd like V6/4x4/5-spd, but the 4x4 is the most important.

I know this is a massive amount of work, and I won't be undertaking it anytime soon (say, a year or two off) but if it's going to be possible, I'd like to start collecting parts.

So, finally, my question: what am I going to need from the 4wd donor vehicle that's not common to 2wd? Obviously I'll need everything between the front wheels and the t-case... do I need to replace the tranny, or can I bolt up the t-case to my existing trans? Then I'll need the donor rear drive shaft... How about the suspension? Sounds like the 4wd springs are different, so I'd get those from the donor (or consider *small* lift at that point)... nice bonuses would be the electric locking rear, etc, but if they're not there I wouldn't cry.

I know that this project will be quite extensive and maybe not very cost-effective (vs. trading) but it'll be more fun and I'll get to know my rig VERY well... I have done some wrenching in my past (including restoring/upgrading my '68 Merc Cougar), but this will be my most extensive project to-date.

Thanks for your help and opinions!

Off the top of my head:

* Front drivetrain (hubs, half shafts, diff, mounts, drive shaft)
* Transfer case (different crossmember?)
* Rear drive shaft
* Center console around shifter

Like you said, you could then swap in either the longer '99 4WD V6 coils all around, or go for some aftermarket lift coils. If you have your heart set on keeping your current 4Runner, maybe start looking around for a totalled '98-'99 4WD auto model that is cosmetically beyond repair, but has an intact drivetrain. Of course the mechanicals from pretty much any '96 - '02 4Runner will work, but the later the model, the greater chance you'll have incompatability issues with ABS, traction control (TRAC), skid control (VSC), and multi-channel brake layouts.

Can it be done? Sure. But I'd look at ALL the costs involved before ruling out a trade or simply selling yours and finding one with the equipment level you want. While we all enjoy our 4Runners, they are not classic cars, and as such, make a poor choice for dumping tons of money into.
The other point you want to consider is that it may be harder for you to eventually sell your current, modified, 4Runner. Buyers may not be as keen on the 4WD transplant as you are.

Andreas

Another option you might consider is putting an ARB locker in your rear axle. You can go a lot of places with that without having to swap in all the 4WD parts that add weight and complexity to your truck. Lastly, you do not have any lift limitations with a 2WD 4 Runner that everyone else with 4WD has to worry about. Just something to consider...

Thanks for your thoughts!
Andreas, I'm happy that what I've been expecting is pretty much exactly what you've said. I'm not really worried about the resale value. One of the reasons we bought this 4Runner (almost 3 years ago now) is that we intend to keep it until it gives up the ghost, which is why I want to increase its "utility". I know that these aren't exactly rare vehicles, though at the same time I've been watching the local For Sale listings (Albuquerque, NM) for about three months now and I haven't seen a single '96-'99 4wd 4Runner (newer than that they're all over $20k).

Regarding a source vehicle: obviously the ideal case would be a "lightly rolled" 4Runner, but would a Taco work? How similar are the drivetrains?

Regarding the ARB locker idea: could I instead try to find a Toyota-stock electric locker? (I don't remember what they're called) In other words, would that be adaptable to my rear (i.e. just change centersections), or could I just swap the axle assembly? That might be a short term solution. Is the electric locker simply actuated by a dash switch, or is it more complex than that (i.e. controlled by ECU or some other on-board processor).

I currently don't have ANY traction control features (ABS, VSC, etc).

You'll need a tranny too. I don't think they've made the tail housings swappable. The Tail shaft is/was different.

Seach on the elocker swap there's lots of info. It requires an ECU http://67.122.16.97/carter The swap requires machine work.

Thanks, and keep the suggestions and advice coming! I'm listening!

Another related question: what are the different types of diffs in the 3rd-gen 4Runners? (or where can I find this info) I saw something about 2nd-gens having different diffs for 4cyl vs. V6, is it the same for 3rd gen?

I recently took a friend Casey out wheelin with his 4Runner that just had the 4x4 conversion done to it. The whole process took only a weekend to complete. Here's a link to a post about the procedures; http://www.yotatech.com/showthread.php?t=29411

There are a lot of people doing SAS conversions to their Taco's and Runners, so getting complete front drivetrains are quite cheap. I recently saw a post where someone is doing a SAS job and I'm sure you could get his stuff; http://home.comcast.net/~4x4freak/wsb/html/view.cgi-home.html-.html

BruceTS-
Thanks for that link! It's extremely helpful! If nothing else, it shows me that it can be done, and not only that, but it has BEEN done now! Granted it sounds like he has some pretty good shop connections, but nonetheless its possible!
Whoohoo! (Now to start saving $$$$)

yeah, i was there for the whole 2wd->4wd conversion for casey's truck. once you have all the parts and the people with the knowhow to get the work done, it's not so bad. it's possible to even do it in one full day if evertying goes smoothly.

steve schaefer (the work was done at his friend's shop) is expected to be coming out with a write-up on the entire process. we took lots of pictures along the way, so there's no shortage there.

good luck if you decide to really get this project going.

Cool, I'll watch for that writeup! I did a google search yesterday and found a 1999 SR5 at a salvage yard that had been rolled, damage to every body part, but all mechanical parts were guaranteed for a year... no price, make offer... If only I wasn't blowing all my cash on the house downpayment right now (of course, then I wouldn't have the garage either...).

But it gives me hope that I'll be able to find what I need! Thanks for your tips, everyone!