thanks for putting up all the pictures. I'm almost thawed out up here in boston and ready to get my conversion finished up too (I have to do everything in my driveway).

thanks for the plug by the way, thats a big help.

 

DAAMMMNNN, Ive been following caligulas but just stumbled upon this...
Looks great man im sure your proud!!

 

was it the drivers side catalytic converter pipe that caused the clearance issues? the 4wd trucks have a different one that looks like it gives more clearance and i was hoping it wouldnt be an issue.

good to know it isnt (a major one anyway).

did you try running it with the 4x2 ECM? i'm not planing to change that unless i have to.

 

I wonder if converting a late model Tundra would be just as "easy"? I just purchased a 2008 4x2 and this conversion looks very doable for the older Tundra's, but what about the newer ones? Do they still have most of the 4x4 wiring already in place?

One more thing, why do you have to replace the upper ball joints? What if you just bought 4x4 front hubs? Would they already have the correct ball joints?

 

this is a bit of an old post, but i can answer some of it. not sure on the newer tundras, the mechanics are probably similarly easy to swap, but the electronics might not be.

as for the first gen, the ball joints are the same, mine just needed replacing. the spindles are also the same, but the actual hubs are press fit into the bearings and can't be removed with out destroying the bearings. 4x4 spindles would already have the right ball joints. (do check for abs though)

 

Can you OR anyone else explain how to remove with a screwdriver. Ive never been able to remove these types of wires, I always break down and buy the pins which Im about to do now.

I have the door open and I keep damaging the pins. I can eventually remove them from the back but I end up denting the wire pin so when I put them back in my 2wd plug they wont stay seated!! Ive used all types of tiny jewelers screwdriver but no luck.


EDIT: Finally figured it out. I was pushing down on the white clip instead of lifting up. Lifted up on the white clips and the pins came right out undamaged. User error as always. LOL

 

Seeing both conversions done on tundra's, I have decided to venture out on my own as well and convert a 2004 sequoia. I believe I have most of what I am going to need to do the swap. I have a couple of questions though. I have both a 2005 and a 2003 late model transmission/ transfer case setup, that will be my donating vicitms. The adapters on both look very much alike. The t-cases do not however. I thought I could bolt up the 05' setup because I wanted the five speed tranny. Too much to convert electrically, not to mention having to rewire the ecm. So best bet was to opt for the 03' late model I have; which is exactly the same as the 04'. Here is my problem though. In order to use the t-case from the 03' I would have to cut a hole in the floor for the 4Lo range because it is manually shifted to achieve this gear range. 4Hi is activated by the internal button on the dash. Seeing how your conversion went, I did not see you mention this in your post. You used the ADD on the front diff, which I have from an 05' tundra SR5. You also used the electric motor on the t-case to shift your 4Lo range. The button setup on the dash looks like the exact thing I will need to make my conversion work. What make and year did you get your drivetrain from? And where did you find the donated wiring harness. This is the hardest part I have been unable to find? I have the front axles, I already rebuilt, and the front arms to convert over they attach to; also from the same 05' tundra SR5. Another thing I noticed was that your instrument cluster had the illuminated lights already in the dash. My sequoia does not have them. I might have to swap out part of the dash, hopefully it will not be a problem. One last thing did your rear axle have a diff lock as well or is it open, and does everything function 4wd wise without any mil faults illuminating the dash?

 

nice, but lets say someone wanted to do this to their 03 (my brother) and has no skills or tools whatsoever... how much would this be to get a shop to do it?

 

sucks that the OP hasn't been around for a year and a half but this is a pretty cool conversion.
As far as cost...probably 30-50 hours at $90 an hour + parts....
Cheaper IMO to sell a 2WD and buy another truck

 

(whistle) thats costly. guess the do it yourself worked out for him. thanks for the reply sorry, didnt notice he wasnt around.

 

i have a 2003 toyota tundra that im converting to 4wd. i have a few questions. behind the passenger side kick panel i have the plug in for the 4x4 ecu, is there anything else that needs to be done to that part of it? the wiring for the front diff is the wiring already in the my 2wd wiring harness, or is that something i need to build my self? where does the tran case wiring hook into? how does the dash buttons for the 4wd connect to the rest of the electrical system? Do you know if the the any of the 2wd suspension parts: control arms, joints, hub and bearings need to be replaced or are they the same as 4wd suspension? The parts i do have: Front Diff., CV Axles, 4wd Tranny, Transfercase, both Drive Shaft and Propellor Shaft.

 

I'm doing this conversion to my 03, too. You do need 4WD spindles from a 1st gen Tacoma, 3rd gen 4Runner or 1st gen Tundra. I'm using a 4.30 front diff and spindles from a 99 4Runner w/ABS. 05-06 Tundra spindles use different/better lower ball joints, so if you use those spindles, you'll need new LBJs. Or you can buy new bearings to have pressed in and source 4WD hubs, which would likely cost way more than used spindles.

Unfortunately, I've hit a snag with the wiring. I'm assuming there were some wiring changes between 00-02, 03, 04 and then 05-06.

I picked up a transmission, transfer case and harness from an 04. All in good shape with no missing wires as far as I could tell. However, my 03 does not have this white connector that is crucial for easy wiring:



All I have is the female side, with all the correct pins in place:



I found the part number for the male connector, but you can no longer order it from Toyota.

All ADD and transfer case connections on the 04 harness ran to a small gray 12 pin connector.

I did have the white connector for the 4WD ECU in place, and with the ECU connected it does make the 4WD lights in the instrument cluster flash, so those circuits evidently work fine.

 

I know this is an older post, but I am trying to do the same thing to my tundra (05 double cab). can you let me know what parts you used for the entire project? From the pictures I can see most everything, but would like to make sure I do not miss anything that I would need for the conversion. Also, are you pleased with the conversion of the truck to 4wd? Thanks in advance!

 

I know it is an old post but after reading about other members work with converting first generation tundra's, I have stated my own 2Wd to 4WD conversion of a 2002 Tundra.
Going well , but did not figure a couple costs like all the miscellaneous nuts and bolts that the salvage yards cut or throw away and are only available from the dealer.

 

Please someone tell me howmuch did this cost because I want to do this to my truck

 

Sooo, the frustration has set in. I started with a flashing light 4hi. Nothing engaged of course and the diagnosis began. I started looking up the first few things about transfer cases and the problems that occur. I found that the actuator was making an effort to engage and beeping. The one thread I found on beeping I can't find again. So I took it all apart.



Transfer case and actuator





The vehicle





Removed transfer case and drive shafts floor jack holding up the transmission





Fork 1 and Fork 2 and the rest of the inside glory of the 5.7 transfer case





This bundle of fun is the inside of the actuator motor the motor works just fine I tested both rods. The problem was the gears on the inside were not catching after a test run

So with all of this work of checking out the case and innards to make sure it all works. Putting It back together reinstalling it and testing it, still doesn't work. So I forced it to go into 4wd then put the truck into gear and saw the front shaft turning and the front wheels not turning. My master mechanic friend said that they also have an actuator on the front end. Tomorrow I will be working on the electrical. Relays and such.

Any advice would be nice. Thanks everyone and if there are any questions about the disassemble, shoot!

 

I think you should start a new thread. Adding to this one is not going to get as many responses.

 

So I have a 2001 Tundra 4.7. My plan is to convert it to 4wd like others on this forum. Did you replace the 2x4 ECM for the engine and transmission for a 4x4 version or did you only change out the chassis control box that controls the transfer case located behind the glove box?

 

I know this is an old question on an even older thread, but since the thread got a few questions after all these years I thought I would answer for anyone that finds this.

I did not end up changing the ECU, i only had to install and wire up the control box for the transfer case and ADD differential (that box does both).

 

Well done guys! I have an 04 Tundra 4.7 2wd, and an 05 4wd donor vehicle (05 has vvt and another gear apparently). Is this a deal breaker, or can i do it with the 05 stuff? Br Jerry

04 Tundy

Donor 05