How-to guide for converting your 2007-2013 Tundra to Full Time AWD capability

how much would you estimate labor would cost if provided the parts??

 

Hey @ViktorG !

I have followed all your Tundra work for a while now and have been blown away!

I have been out of the scene for a while but I used to be pretty active on a couple forums and I originally built up at 2007 RCSB Tundra that was super charged and had a 4link rear suspension along with a lot of other mods. Then I moved on to a 2011 DCSB that Brian Jowett helped me swap a landcruiser transfer case into and of course I ended up supercharging that one as well. It was an amazing truck that I am sad to say I sold and wish I never had.

I haven’t had a Tundra since 2017 and now here I am back into the tundra seen ironically with a 2017 DCSB. I would really like to swap a full-time awd Land Cruiser/lx570 transfer case into it, and I wanted to know if that is possible. The original one I purchased from Brian and had him do the modification needed, which I believe was changing the front driveshaft plate and he made some modification to the harness to ensure that 4hi and 4lo worked. But aside from that, there was nothing else needed that I remembered. Would it be possible to do this with a 2017? I much prefer it to be full-time all wheel drive anyways. I appreciate any advice or help you or anyone else on here could give me in completing this project.

I sent Brian an email, but no reply and I’m not sure if his jowett engineering email still works or if he is still in the scene.

V/R

Alan

 

Did that new transfer case come with the actuator? Looking at cases now and it's not much more for a new case from certain dealerships than a decent used case - that is, IF the new case comes with the actuator. Else, I'll prolly get a used case.

How did the swap go?

 

No one to date has tackled fitting a 2.5 Gen with a 2.0 Gen transfer case, they were of different manufacturer. The LCs maintained the same TC as the 2nd Gen throughout the 200 series. The Sequoias maintained the same TC as the 2nd Gen as well, until the 2023 model year.

 

@blenton I picked up another Sequoia t-case over Christmas break because it was too good of a deal to pass up on (prolly some form of illness there!). So I might have found it on Ebay from a 2011 Platinum that was very clean with 110K miles and from the South, which means it was probably never out of 2WD. Search for "5.7 Sequoia Transfer Case" on Ebay. I also might have found the same or similar wrecking yard as on the Ebay listing and reached out to them directly asking if they had any 2011ish t cases for a Sequoia, and don't you know, they had one! I picked it up for $1200 with freight shipping on a pallet and it is perfect. I'll probably be swapping this into my truck and giving the Sequoia t case that's in it now to my nieces husband for his 2007 Crew Max. My current one was from New York state and had a lot of corrosion and miles, but it still is fine, I just like the idea of a shiney, newer one.

I'm not sure what a new t case would cost from Toyota, but there are deals to be had for used. Ebay just chokes the sales not only with their listing fees but taxes as well. I found that out when I sold my original Tundra t case after the swap. I think I cleared less than $200 and just wasn't worth the trouble of shipping.

I do use AWD quite a bit and really don't see a ding in the fuel mileage. It's really nice even when the roads are wet.

Keep us posted and good luck!

 

Thanks @07 Tundra Steve . You, sir, appear to be an addict..

The other day, I found two decent looking but higher mileage units out of California for around 1300 shipped. Problem is, I’ve been burned pretty good on Fleabay before so I’m a little gun shy right now; of those instances, one was a motor for an accord I was owned that showed up with gravel in the valve cover among other major issues (sold as “runs great, just pulled”), and a pile of impressive knockoff Milwaukee batteries priced just right to seem authentic but to a keen eye were definitely fakes. I eventually got my money back on both but only have a long headache of a process.

Anyways, LKQ had some a while back but is hit or miss now. Carparts. Com has several but for less than 200k grade A parts are 1400+. I could get a new unit for 2300 and change plus 150 shipping from a couple of dealerships.

But… if the new ones don’t come with the actuator attached that’s another 1000 dealership/ 500 rock auto part.

 

Took the plunge… ordered a used T case off of fleabay. Hopefully it’s good to go; I actually found a user on here comment on the salvage yard that I purchased it from, saying they frequent that particular yard and they have good used parts.

We just woke up this morning to more snow.. so it reminded me that I need to do it. Yes, need. Haha. Now I just need to find the time to do it.

 

@blenton , How's the T-case swap coming along? I've been busy lately, but just revisited this thread and wondering if you're getting things together for the swap.

Let us all know if you need any help, especially with the electrical. I was a bit fuzzy on understanding what needed to be done with the wires and pins. When I didn't get it right, I could hear the t-case shift, but not the front diff. It was a wiring/pin issue that I had to figure out. Ping me if you have any trouble.

Shorten your rear drive shaft prior to the swap, even if you have to drive your Tundra in front wheel drive (via 4WD without the rear drive shaft) and make sure that work is done right. I still have to work out the balancing on mine and I wish I would have confirmed the work was done right from the git-go. Should have been a non-issue.

All said, AWD is absolutely SWEET, no matter what the road conditions!!

Best,

Steve

 

@07 Tundra Steve Thanks, man. I just might take you up on help on the electrical side..

The tcase lock switch just showed up this week so I should have all the parts to make it happen. I also called a buddy about getting the driveline shortened; he referred to me to a shop in town I’d kinda forgotten about, but had them build a a new driveshaft for my old bronco years ago. They seemed well acquainted with the Toyota 2 piece rear driveshaft and recommended inspecting the intermediate joint. Else, they said they rarely see issues with them. 2-3 day turn around if they are busy.

But my mrs had a small mishap a few weeks ago and I’ve been playing mr mom for littles. So I’m a little behind and a little more worn out than usual from karting kids around, making sure they make it to school, making foods, etc. But I’m not a mac n cheese kinda dad so we’ve been eating well - almost as well as we do when the mrs is in charge! I tend to forget that there are more fruits and veggies than apples, oranges, and carrots. Haha.

So it might be a little while until I get to it. I might just take some time off work (not as easy as claiming PTO or Vacation days like a regular 9-5…) and turn my phone off for a week while I get my basement finished, fix the bruises from Bambi’s Stoopid thick skull, and clean out my shop. Then take another week and get the family outta dodge! I have to go either 1000 miles from home or where there isn’t any cell service to feel unplugged. I’m sure I can figure that out if I try.

Thanks again for the help. I’m sure I’ll be asking some questions.

 

Sorry for the slow update guys!

Had a bit of a headache with regards to the driveshaft. The place I got it done by originally cut it too short (their fault) so that caused a delay. Then they didn't balance it right, which only became obvious once I went on a road trip and got it above 70mph. Eventually they did end up balancing it properly, but by then I'd forgotten about posting my updates here.

The truck drives like a dream. I've been using it for over a year now with no issues. All the driving aids work, ABS, TCS, ASM, and the factory diff lock switch works perfectly with the amber LED I wired up as an indicator.

Using it in 4LO with the diff open to manuever my RV at low speeds has been a pleasure. Really makes backing it up into my steep driveway a breeze.

The only advice I have for anyone doing the swap is to get a proper lift and transmission jack. Getting the new T-Case on took me 14 hours of fiddling. It sucked.

 

is it possible to post all the items bought in order to do this?
is there anything else besides jf3ta case, ecu, wiring harness, sequoia cluster.

 

I honestly forget exactly what I bought, but I based it all off this

So here is what you need to make this swap happen:
A 2008+ Sequoia T-case. I got mine from a wrecker from a 2008 model with 80000 miles on it.
A Sequoia 4WD ECU. I bought a new one for a 2009 model. For some reason the 2008 and 2009 part numbers and wiring diagrams were slightly different, I took a gamble with the 2009 one and it is working fine. Probably the 2008 would work just as fine too. (PN 89533-0C022)
A Sequoia center diff lock switch – fits directly into the Tundra dash. (PN 84725-0C130)
A pigtail for the 4WD ECU wiring harness since the Tundra harness does not have the center diff lock wire going to the ECU. (PN 82998-12870)

Have your rear driveshaft shortened by 1¼ inches and rebalanced.
Ideally, have the front shaft lengthened by the same amount. A Sequoia front drive shaft might work too, but I don’t know that for a fact, possibly the front diff flange or position in relation to the t-case might be different. I will get a buddy at Toyota to measure one for me when he gets a chance. As mentioned, I reused the Tundra front shaft, but it lost about 35% of the spline engagement from what it is stock. I don’t think it will be a problem considering how much beefier those splines are than the ones inside the transmission for example.

Remove drive shafts.
Remove stock T-case.
Send your drive shafts out to get shortened/lengthened.
Install Sequoia T-case.
Install modified shafts.
Swap the 4WD ECU (on the right side behind the glove box).
Install the center diff lock switch in the same spot as Sequoia has it.
Install the pigtail wire into pin 12 of the large 4WD ECU connector.
Wire that pigtail to ground thru the center diff lock switch.
Done!

The center diff lock switch arrived this afternoon. I expected it to have some bigger pins on it, so I could fabricate a wiring harness for it, but the pins on it are really small. What I ended up doing is I got an old connector from a used Lexus engine wiring harness we had laying around, and ground it down from 16 pin to a 5 pin so it could fit into the center diff lock switch.

Since most of you don't have a spare Toyota harness laying around, you would have to order the connector and 4 terminals with pigtails from Toyota. Connector is PN 90980-12368. Terminals are PN 82998-24290 or 82998-24300 (get whatever is cheaper).

I connected 3 of the leads to the conveniently located Tow/Haul harness, where I got Illumination and Ground from. Last terminal goes to pin 12 on the 4WD ECU.

I also installed an indicator LED right next to the center diff lock button to tell me when the diff is actually locked. Run power to the positive side of LED and run a wire from the negative side to pin 14 on the 4WD ECU. It works perfectly!




The green and yellow wires for illumination apply ONLY to the tow/haul switch.

Other switches all use different color wires.

On the tow/haul the green is ill+ and yellow is ill-, but some other switches have yellow as ill+ etc.

Let me know which switch you are tapping into and I'll tell you the wire colors for the illumination circuit.​

What I DO remember however, is that I did not specifically need the "Terminal, Repair with Wire" Part number 82998-12870. The other pigtails I orderered were exactly the same and literally $38 cheaper (had to buy the one wire from the stealership and got bent over as usual when dealing with them). So just order an extra pigtail in lieu of 82998-12870.

​

 

I'm considering this project as I plan to be supercharged next year. If the OP or other members that have tackled this project have any insight it would be much appreciated!

My question is if purchasing a 2014+ transfer case would I need the same year TC 4x4 module or would other years work?

And

Would wiring be the same as stated previously?

Anyone have install pictures of wiring/diagram?

Thanks in advance.

 

2007-2013 only. 2014 uses the borg Warner where the 07-13 are aisin transfer cases.

 

I see, I thought I read someone saying the transfer cases in the Sequoia remained the same until 23'. Or are you saying ours(Tundra) TC's change after the 2014 model year. I understood this has not been done in a 2014+ Tundra, just was not clear on the use of different year Sequoia TC's and the TC ECU's being interchangeable.

I'll keep looking for a clean 2013 Sequoia TC and earlier. This mod seems simple which makes me second guess the little things.

Thanks!

 

The Sequoia transfer case was an Aisin until 2021, probably so that they could continue to have the AWD w/open center dif cred which I don't think was available with the Borg/Warner that was used in the Tundra 14+.

Hypothetically, you could use a 4WD ECU from any model year, but just in case there might be some anomalies, I might suggest trying to get one within a few model years just to avoid any hiccups like software revisions.

Torsen differentials

 

As @Wynnded stated not sure of any wiring v issues. But should be alright. I need to look at your info as I missed you got a 2013...

 

Yeah, no worries. I appreciate the replies and additional insight.

Seems it's as simple as adding/powering up a diff switch and splicing into the Sequoia TC ecu's diff lock pin? Of course after all the parts swap.

Is the consensus to shorten the rear driveshaft 1.25", I read on the other forum someone did 1.4" and I'm assuming the shortening of the shaft does not change based on cab size.

I found a decent 2014 Sequoia TC(80k)/13' ECU/13' front driveshaft all at the same yard. See what I can get em for as a package deal.

Thanks again!

 

On the Regular Cabs you don't have to do anything with the driveshafts. Plug and play.

 

Let me see if I can find the info but I believe RCSB does not have to shorten the driveshaft...

 

looks like i need to refresh when posting. thanks for info, was looking at viktor's notes when he did his. I need to do this awd thing!!! I spin way too much in the rain. ha

 

You, on the other hand will need to have the rear drive shaft shortened . . .

 

I need to go over his thread more closely, did not see that mentioned. Makes it that much easier, sweet thanks!

 

Here was my write up in Viktor's thread about 8 years ago.
https://www.tundratalk.net/threads/...ed.542745/page-6?post_id=7109874#post-7109874

 

Finally after all these years got the Sequoia t-case and completed the AWD conversion. Thanks Viktor and @Wynnded !

 

I just followed the path created by @Jowett and @ViktorG. Welcome aboard!

 

Oh man. Yes! @Jowett who brings all the good info and pain staking cross references the parts for us

 

I added a cheap $10 momentary switch for the diff lock. Works as intended, mounted below tow/haul and alsd button lights up when locked.

 

Easy button.

 

I couldn't believe how easy and fast it went. About 2.5 hours swapping t-cases and driveline install. I had the hardest time wiring. I got hung upvon the a25 connector. After 2vhours I realized they were showing the front where I was looking at the back. It wasn't until I took a picture of the plug and saw the numbering on the back and the wiring manual said "front" in the pdf. Anyways good stuff and it works great!