PreRunner 4x4 Conversion Journey Thread

Swapping out valve bodies is probably much easier than swapping out output shafts. When I first was sourcing out the 4x4 parts for my swap I had first purchased a older model transmission with the cable not knowing that my 03 was electronic. Later on I found out about the difference and I did look into either swappin valve bodies or output shaft but decided to find an 03-04 which i did.

Anyway i kept the transmission I first got and decided to crack it open to see what it took to get that output shaft out. Let me tell you its a lot of work to take it out and then youll need to also take your other transmission apart just to get the output shaft in. If youre not familiar with automatic transmissions this would definitely be a a job for a specialist. Totally doable but requires a lot of work. Just thought I share that.

 

Oh for sure, I don't think I'd ever try to do that myself haha, if it came to it I'd pay a shop to swap the shaft. Although it sounds fun to get to play around with taking apart a transmission in a non-consequential way. If all goes well I plan to just keep my A340E as a backup so maybe someday I'll try rebuilding it.

 

As I continue to do as much prep as I can ahead of the major swapping coming up, I decided I wanted to extend the VSS cable ahead of swapping the trans so that I can just plug and play come time. Big thanks to all who've provided details on this mod previously, and @mjhenks your close up shots and detail on the install was very helpful.

Everything started off well, I cut off the pigtail, soldered in about 16" of new wire, sealed everything up etc. Once I got under the truck to connect the newly extended plug to the harness, I was having a bit of trouble holding everything together, so I stuck a magnet on my helping hands setup and put it under the truck which actually worked great lol. Before I sealed up the now fully soldered harness with heat shrink/tape/loom I wanted to make sure that the speedo actually still worked after extending it, so I took it for a quick drive. At first it worked great and I assumed all was well, but after a few minutes, the rear diff locker button all of the sudden lit up (mind you, my truck is not TRD and I do not have a rear locker lol), and I noticed the odometer went blank. I assumed I screwed something up in the wiring, but when it got home I realized because I left the soldered connections bare for the test drive, they probably ended up touching each other and shorting out. Sure enough, I pulled the 10A gauge cluster fuse in the kick panel and it was fried. Rookie mistake, but popped a new fuse in and buttoned up the harness and everything works great. Moral of the story, if you want a rear locker, just blow your gauge cluster fuse .

The main disadvantage of doing this before the new trans and transfer case is in is I of course can't precisely measure what length the cable should be, but I feel confident I gave it enough slack and can route it in a reasonable way come time for install.

 

Anyone know if I'll need to drain any engine oil to replace the rear main seal? I'm planning to just pop the seal and not remove the backing plate/RTV. I would assume I'd be ok not to drain it but haven't found specific guidance there. For the 3.4

 

Nah you don't need to drain your oil to do the rear main. Oil level is way below that

 

Sweet, thank you!

 

It's a beautiful sight, big parts lined up ahead of starting the removal work. I'm hopefully going to be filming the process a bit, will get all my tools together tomorrow and maybe start on the trans removal. Also quick highlight of putting the cleaned up torque converter back on, this can be a little tricky and you have to make sure it's fully seated. You will probably know it when you get it on right but the FSM does have a section on how to check this. From the line of the bell housing, the face of the bolt area for the torque converter needs to be at least 17.95mm recessed. I also made a small bracket to hold it in place while installing.

 

Respect for making it happen! I remember when I did a simple manual swap on my daily in high school and when I went looking for resources, people told me to not bother and sell it and buy a car that was manual from the factory. Glad I didn't listen.

 

Impressive, very nice to watch it all come together.

 

Very successful day one, I didn’t actually get started until about 2pm and I wrapped up the day with the the transmission ready to be dropped, just need to remove the bell housing to block bolts and it will be free. Thankful to be doing the job in a proper garage with smooth floors lol. I had to bring all the tools I’d need (or might need) over to my brothers where I’m doing the work, so enjoy a nice knolled shot of the bed. Excited for day 2

 

It’s out! Really the only difficulty I hit was the bell housing was stuck to the block pretty good. I ended up hitting the bell housing near the access plate quite a bit, and wiggling from the back. Took maybe 20 minutes of fussing but eventually came free.

 

Pretty sure we share a similar OCD gene.

 

Haha I can't work on the truck without being organized

 

I kind of got my ass whooped today, but ultimately the A340F is installed (including a new rear main seal). I'm doing this job solo so there's just a few things that were harder considering that. I also ran into a few issues that sucked up more time than I had hoped for:

1. I had to swap over the oil temp sensor from the A340E, but what ended up being annoying was you can't remove it without changing the angle of the oil cooler line adjacent to it, and you can't really get a wrench on the oil cooler connector without taking the position sensor off...
2. I wasted over an hour by driving back to my house to get a seal puller I forgot, only to realize I didn't bring my house keys with me (they're on my truck keys and I was borrowing my brothers car)
3. It's a PITA just getting everything torqued evenly, in particular the bell housing bolts to the block, you have to string together about 3ft of extensions and go back and forth constantly, and the A340F has way less room above the transmission to navigate given the increased size of the tail housing. I also forgot to get locktite for the flex plate bolts, so wasted more time running out for that.
4. I figured out the hard way that the 4Runner and Tacoma do not use the same trans mount for the A340F. This mount came with the transmission (that was from a 4runner), and when I went to reattach the crossmember to the mount, the holes are like 3/4" offset. I looked up the part number and sure enough its different (the tacoma is part number

$145 12371-07030 Engine Mount Insulator

12371-07030 and the 4runner is 12371-62120). So, that's kind of holding me up at this point as I'm not going to attach the transfer case without that buttoned up. I'm gonna call the dealership in the morning and see if they happen to have one in stock or how long it would take to order one. I would really rather have an OEM one in there.

Tired, but it's chugging along well so far, and mostly enjoying the process.

 

Looking good man. When I did my conversion I also did this on my own. It wasnt too difficult but another person would have been a bit easier to get the transmission off and the new 4x4 transmission on.
I used a regular jack when I took off the 2wd drive transmission. It was a PITA but I got it out. Later that day I went to Harbor Freight and bought a transmission jack. I dont see how i wouldved gotten the 4x4 transmission on without it. The transmission jack made so easy to get the new transmission on there for sure.

Im sorry if I missed this. Are you doing the conversion at a shop? I read that you had to go back home for a tool?

 

I got my a340f out with a floor jack and that was absolutely sketch. Will definitely need to get a trans jack added to my arsenal.

 

Oh yeah it was be crazy hard without the transmission jack. It’s funny because it’s one of those things that most people buy and use one time, so I figured one would pop up on marketplace cheap, which it eventually did lol. It’ll be nice for the transfer case too I think.

I’m just doing it at my brother’s house! He’s got a nice garage with smooth concrete floors, whereas my garage at the home I rent is now my shop (it would be way too small to park the truck in anyway), and my driveway is super crusty, so it sucks for anything requiring a creeper. Also technically my lease specifically states no automotive work lol, I can only imagine my landlord has probably had some weekend warriors spilling oil onto the driveway to include that clause.

 

Keep a look out on marketplace I bet you can find one for $100 or under, people get them and use them once and then they take up about twice as much space as a normal floor jack lol

 

Day 3 update: I thought I was going to be hung up on moving forward until I got the new trans mount, but I ended up getting the torque converter bolts, oil cooler pipes, and all of the wiring hooked back up. And more importantly I also got the transfer case installed, which was a bear. A key realization I had was that the transmission was in park initially, meaning I couldn't wiggle the input shaft of the tcase into the gears on the transmission. Once I realized that and put it in neutral, I got it hooked up shortly after. Very glad to be done with the majority of the heavy lifting (sans front diff). My VSS extension was perfect size as well. I also grew tired of the constant condensation in my shitty aftermarket turn signal assemblies, so I picked up new OEM ones and threw those in too. The trans mount should be at the dealer tomorrow, so I'm hoping to get that and the crossmember fully installed, then pop in the rear driveshaft, fill up the fluids, and take it for a test drive in 2WD to make sure everything feels a-ok with the transmission.

 

exciting stuff man. You'll love that truck even more once its reading to 4x4