Replacing my '03 LX470's Transmission (1 Viewer)

[128keaton]

@128keaton Hope it still working will and shift normally.

I'm trying to help diagnose a leak. The leak may be at adapter case. It's on a 06LX ,so fill plug is on the adapter case. I suspect the 03 is very similar to the 06 other than fill plug.

If you can post pictures of your adapter case inside, front, back, etc.. It would be very helpfully.

Seems to be, for the most part, fine. Sometimes shifting feels a bit delayed or 'sticks' but it is not terrible and I'm hyper-vigilant since I had my hands inside that transmission.

I don't have very many photos of the adaptor case, I'm still looking, but this is what I have so far:

 

[2001LC]

You may want to do anther 12qt flush. Your old LC filter really looked bad and you mention the 4runner was very dark fluid when you drained it..

Thanks. I'll watch for more picture posting. Hey may be the 4 runner adapter case will give me the clues I'm looking for. I need to see inside front case.

 

[Zjohnsonua]

Stumbled on this and it looks like some meaningful time has passed. How's this doing now?

 

[128keaton]

Stumbled on this and it looks like some meaningful time has passed. How's this doing now?

Still rolling fine. I’m pretty sure most of my “shifting” issues I have now are really results of having a new driveshaft and transmission mounts, but worn motor mounts and very worn trailing arm bushings.

 

[Velogas]

Thank you for documenting this!

We are about to replace our ‘03 trans with a used ‘03 trans with right at 100k mi.

How hard was it to get to the plugs/lines as you install the new trans?

I may just install a new radiator at the same time.

 

[128keaton]

Thank you for documenting this!

We are about to replace our ‘03 trans with a used ‘03 trans with right at 100k mi.

How hard was it to get to the plugs/lines as you install the new trans?

I may just install a new radiator at the same time.

Really not that bad. the transmission cooler is separate so I removed the whole unit for cleaning.

 

[Velogas]

Wait. The 2003 trans cooler is separate!?

I feel dumb.

Really not that bad. the transmission cooler is separate so I removed the whole unit for cleaning.

 

[Velogas]

Any advice for stabbing the transmission? Almost done! But can’t get the trans mated up to the motor.

Well I'm driving an LX470 with a working transmission again! Success! The A750F from the 4Runner worked! Shifts very smoothly. Filled with 12.75 quarts (roughly) of ATF. No leaks so far! Super happy!

 

[128keaton]

Any advice for stabbing the transmission? Almost done! But can’t get the trans mated up to the motor.

Lol I wish I had any, it kinda fell into place! Make sure the jack is level!

 

[akaAquaman]

So I see that the filler plug was originally on the extension housing. Where did it get moved to after you swapped extension housings? Also, what did you have to do to gain access to the bolts holding the extension housing to the transmission?

 

[Zjohnsonua]

I've got the cores on hand to try this build myself. If Keaton hasn't chimed back in, I'll take a look at the parts after work and try and get some photos and explanations for you.

 

[Doug73]

Awesome write up and documenting the process! I joined this forum just to thank you!

I have a 2005 4Runner 4wd w/2UZ and lost R and OD. Looking for a salvage transmission, and the A750F from 4Runners are priced much higher than Tundras or Sequoias. I asked around about swapping an A750F from a Tundra or Sequoia into my 4Runner and nobody can say whether it would work or not.

Your write up shows it can be done as long as the output shaft is the same length (can replace with the one in my 4Runner if different), extension housing can be swapped from my 4Runner, the shift linkage can be swapped, and the sensors can be swapped if the pinout is different. I guess the main transmission wiring going to the solenoids would also need to be checked.

Anything I am missing?

Again, great write up!

 

[Zjohnsonua]

@Doug73, @Keaton's homework goes a long way here. His researched helped me a bunch with my swap.

Solenoid harness is the same. Just watch out for tailshaft lengths. The rest is swappable so long as you stay in the same year range. Toyodiy.com is your friend for comparing bills of materials

 

[Doug73]

Thanks for the info!

Looks like the output shaft and rear extension housing is different, so they need to be swapped. Extension housing is easy, but the output shaft will be a PITA.

I never disassembled the internals of a transmissions before (I have done a full valve body disassembly), so I am hoping patience, self documentation when disassembling, and a good set of c-clip pliers is all that is required. I know a few items need to be placed back in the same orientation (c clip openings, cupped retainers, etc).

Good video documenting a full disassembly of A750E:

 

[Zjohnsonua]

I'm all for the endeavor of tearing into a transmission, but I'd encourage paying the few extra hundred bucks for the correct transmission with a factory build. These aren't so old that remans are a must, and decent used units can be had for ~700.

 

[jruise100]

I'm all for the endeavor of tearing into a transmission, but I'd encourage paying the few extra hundred bucks for the correct transmission with a factory build. These aren't so old that remans are a must, and decent used units can be had for ~700.

I found it difficult to find a LC 100 used trans with relatively low miles. Mine is an '03. Until this morning I didn't know about the output shaft difference in A750F's.
THANK YOU KEATON! For this thread!

I found a 2014 4runner trans with 92K on it. LQK $1100. I'm on the fence about the output shaft swap but this thread is a confidence booster. I've watched the Curmudgeon videos but he's doing a complete rebuild so it's difficult to see what internals can be left together.

Keaton, if you see this, Please post a summery of the shaft swap. Thank you!

 

[Zjohnsonua]

I found it difficult to find a LC 100 used trans with relatively low miles. Mine is an '03. Until this morning I didn't know about the output shaft difference in A750F's.
THANK YOU KEATON! For this thread!

I found a 2014 4runner trans with 92K on it. LQK $1100. I'm on the fence about the output shaft swap but this thread is a confidence booster. I've watched the Curmudgeon videos but he's doing a complete rebuild so it's difficult to see what internals can be left together.

Keaton, if you see this, Please post a summery of the shaft swap. Thank you!

Mine had records showing over 300k miles on it before I pulled it from LKQ. I've since put a HARD 30k miles on it and it's chugging along great.

I would not hesitate on a 200k-ish trans.

 

[jruise100]

Mine had records showing over 300k miles on it before I pulled it from LKQ. I've since put a HARD 30k miles on it and it's chugging along great.

I would not hesitate on a 200k-ish trans.

The one I'm replacing has about 230,000. Practically zero off road. I did tow a 4500lb boat about once a month for approximately 10 years.

 

[128keaton]

I found it difficult to find a LC 100 used trans with relatively low miles. Mine is an '03. Until this morning I didn't know about the output shaft difference in A750F's.
THANK YOU KEATON! For this thread!

I found a 2014 4runner trans with 92K on it. LQK $1100. I'm on the fence about the output shaft swap but this thread is a confidence booster. I've watched the Curmudgeon videos but he's doing a complete rebuild so it's difficult to see what internals can be left together.

Keaton, if you see this, Please post a summery of the shaft swap. Thank you!

Honestly it’s been a few years since I’ve done it and I can’t really remember, all I did though was take it apart and put it back together in the same order. Cleaned everything with new ATF. Used the FSM to some degree. Bought a seal kit, used them when needed. I don’t recall anything being too difficult, just make sure you keep everything in order. The FSM should detail the order of clutches and whatnot. Good luck sir!

EDIT: Post 13 has a great PDF
EDIT 2: also sorry I never posted much else on this, been busy, I don’t have much else to post in terms of pictures, but if I ever have one apart again I will take more haha

 

[jruise100]

Honestly it’s been a few years since I’ve done it and I can’t really remember, all I did though was take it apart and put it back together in the same order. Cleaned everything with new ATF. Used the FSM to some degree. Bought a seal kit, used them when needed. I don’t recall anything being too difficult, just make sure you keep everything in order. The FSM should detail the order of clutches and whatnot. Good luck sir!

EDIT: Post 13 has a great PDF
EDIT 2: also sorry I never posted much else on this, been busy, I don’t have much else to post in terms of pictures, but if I ever have one apart again I will take more haha

I'm super stoked you made this thread! I can't do a project like this and take pics. I'm very thankfull for the pdf. I swapped the internals making many trips back to my pc to look at the pdf and crumudges video. I wish I'd taken more pics of what I did. I mostly pic'd the snap ring placements. I have them back together and am waiting on some seals, thread seal lock, toyota trans fipg and need to order the correct bit for the fly wheel bolts as I'm going to do the rear main seal whiles the trans is out.

I did keep my original housing as I noticed there were some fluid ports on the aft end that the 4 runner housing didn't have.