1st Gen 4wd Conversion 2004 Prerunner

Hi All,

I've been trying to read my way through all of the threads on here about converting my 2004 prerunner xtended cab automatic to 4wd and have a couple of days under my belt so far in doing so but I've got a couple of questions tho and maybe you can give me a point in the right direction...

BTW I'm the original owner and it only has 80k miles and its in insanely mint condition so no, I don't want to sell it and buy a 4wd...(before someone jumps in here and makes that suggestion

- I would like to do the work myself but would need a walk-thru of some sort, I've seen a few sped up videos but nothing super clear about the process. Anything like that exist that I haven't found yet?

(I should add that I have all the repair manuals and Haynes manual, just any supplemental information would be great)

- I'm a little confused as to which specific transfer case to get, and i'm not sure whether to go ADD or J-shift. Pros / cons of either / suggestions?

- Sourcing parts: I would like to get the best parts I can, and I don't want to swap out my barely used trans for a super high milage one, but i'm not sure i have the skills to use the one I already have and swap out whats needed. Any opinions on SP Precision XP Transmissions? Any suggestions on other places (besides eBay) to source parts?

- Parts list: I've seen lists cobbled together, so I have a rough idea of what I will need, but if anyone has something definitive they could share here I would be grateful.

TY!

 

Transfer case wise starting in 2002 I think going from 2wd to 4wd turned from pushing the transfer stick to just a button. The older pushing the transfer case stick is a j shift. ADD stands for automatically disconnecting differential. This would essentially unlock and lock the hubs at the diff. If you don't go for ADD you need to manually locking hubs. Its 50/50 IMO. ADD cv axles are bigger but manual hubs allow you to run a front lunch box locker. ADD is more popular then manual locking hubs if you just go to a junkyard for parts.

 

Being a 2004 youll need a 2003 or 2004 transmission. The 95-02 transmissions are different, alternatively you can swap the valve body. @Lfaub03 was the first to do that and is sorta outlined in his build thread.
https://www.tacomaworld.com/threads/lfaubs-4x4-conversion-camper-build.420105/

I would go manual hubs and jshift for ease of install, but parts are definitely more difficult to come by. Parts gathering was the worst part of my swap.

 

Any suggestions on how I can identify the gear ratio i have in my rear dif lock?

 

This thread should give you the info you need to determine your gear ratio in back.

https://www.tacomaworld.com/threads/oem-gear-ratio-chart.365138/

If it has a locker it's almost 100% 4.10 though.

 

On the transfer case. As said above, the J-shift is going to be the one you want, with manual locking hubs. That makes the install A LOT easier.

People say the ADD CV shafts are thicker... and they are... but, I've never actually broken a manual hub shaft. Every time I've broken a CV it's been in the bearing cage... which is the same on ADD and Manual.

Also, if you break a manual CV you can unlock the hub and get to a better place to change it. You can't always do that with an ADD shaft. Also, contrary to popular belief it's easier to change out a manual CV than an ADD CV.

 

When picking up a transfer case, you need to make sure you have the right one. IIRC there are at least 2 configurations. One has the stick coming out the top, one has it coming out towards the front. It depends on 6cyl/4cyl, Man/Auto.

I can't remember the specifics. I just bought my Trans and Tcase out of the same truck that was a 6cyl like mine is.

 

Input gears, 23 vs 26 depending on the engine config.

 

Yes

 

Isn't that only for 5-speeds? I thought most of the auto trans models had 4.30? I know my '98 4runner (auto trans with rear locker) does.

 

4runner and Tacoma are not the same.

Just about the only way you get an automatic 1st gen Tacoma with locker with anything other than 4.10 is if it's special order.

 

As mentioned, 4Runner is different.

Can confirm as I owned both a 4Runner with rear locker and Tacoma with rear locker.

 

Gotcha. Good to know. Thanks for clarifying.

 

Regarding the A340E I have, I'm seeing people saying that: "03/04 guys usually swap the output shaft from an A340F and use their existing transmission"

Other than the output shaft, I believe the fluid pan and filter also need to be changed. Anything else? Wondering if this is the right way to go or not for me, since my transmission has such low mileage. (well relatively for this year truck anyway)

 

Just so you're totally aware. I believe changing the output shaft is basically just shy of a Transmission rebuild.

People do it, but it may not be as easy as it sounds.

With an 03-04 it's probably the best way to go though.