Connecting a GS450H to an existing Transfer Case?

[nkiernan]

GS450H GEARBOX > Rubber Mount > Bolted to driveshaft > ||| Driveshaft was cut + OE Gearbox Shaft was cut and Welded ||| > OE Gearbox driveshaft >> Insert into Transfercase

Any photos?

[TinkerTan]

I don't suppose you have any photos of the GS450H without the tail piece on?

I apologize for neglecting this thread! I am just picking up this project again. I just fetched a 2007 Tundra for sub $1k last week! I was about to use a 2005 Cayenne for the project but a 4x4 pickup truck is my preference... Next week, I should be able to test fit the JF1A transfer case shaft on my L110F transmission output shaft (When I realized the L110 was a no-go, I bought a L110F). I still need to go through the L110F tail housing to see if I can easily mill my own and transfer L110 tail housing Pawl assembly into it (that and the output shaft speed sensor are essentially all that are in the tail housing) to sell people, to expand the supply of 4x4 capable L110 gearboxes... it may me more difficult/expensive than what would be feasible, especially since the output shaft is not the same as the L110F either. I have the ability to cut splines/gears with 4 axis cnc milling but I don't have the ability to harden/temper my own parts.

Attached are my photos of the internals of the L110 / GS450h transmission tail housing (circa Jan 2021 - I didn't think to post them or check this thread at the time, sorry).

[Jacobsmess]

What I'd love to see is adapters for different propshaft flanges to the exg spline on the gs450h. Any chance you could measure the gs450h output shaft splines for me? Major diameter, nope diameter and number of teeth I guess. Thanks

[celeron55]

What I'd love to see is adapters for different propshaft flanges to the exg spline on the gs450h. Any chance you could measure the gs450h output shaft splines for me? Major diameter, nope diameter and number of teeth I guess. Thanks

I already posted the number of teeth and major diameter 4 years ago: viewtopic.php?p=11390#p11390

[Jacobsmess]

I already posted the number of teeth and major diameter 4 years ago: viewtopic.php?p=11390#p11390

Only got the number if teeth there from what I can see but useful nonetheless... Although unfortunately the rest of your post suggests it's unlikely I'll find a replacement flange with my required bolt spacing.

[celeron55]

Only got the number if teeth there from what I can see but useful nonetheless... Although unfortunately the rest of your post suggests it's unlikely I'll find a replacement flange with my required bolt spacing.

The diameter is in the photo with the calipers. The sealing diameter also.

[robertwa]

I apologize for neglecting this thread! I am just picking up this project again. I just fetched a 2007 Tundra for sub $1k last week! I was about to use a 2005 Cayenne for the project but a 4x4 pickup truck is my preference... Next week, I should be able to test fit the LF1A transfer case shaft on my L110F transmission output shaft (When I realized the L110 was a no-go, I bought a L110F). I still need to go through the L110F tail housing to see if I can easily mill my own and transfer L110 tail housing Pawl assembly into it (that and the output shaft speed sensor are essentially all that are in the tail housing) to sell people, to expand the supply of 4x4 capable L110 gearboxes... it may me more difficult/expensive than what would be feasible, especially since the output shaft is not the same as the L110F either. I have the ability to cut splines/gears with 4 axis cnc milling but I don't have the ability to harden/temper my own parts.

Attached are my photos of the internals of the L110 / GS450h transmission tail housing (circa Jan 2021 - I didn't think to post them or check this thread at the time, sorry).

Glad to see you back at this project! I am also using the LS600H transmission in my build and would be interested to see if there is another transfer case compatible with the stock transmission that is not full-time AWD to help improve range when AWD is not needed.

[TinkerTan]

Glad to see you back at this project! I am also using the LS600H transmission in my build and would be interested to see if there is another transfer case compatible with the stock transmission that is not full-time AWD to help improve range when AWD is not needed.

Indeed, the L110F output shaft does mate to the JF1A transfer case on the 2nd Gen Tundra with 4.7L 2UZ and 4.6 1UR. I have not been able to test a JF3A and won't likely have a chance to in the near future.

I just pulled this out of my truck a half hour ago to verify fitment of the shafts. Indeed, I do need to get a larger ID shaft seal for the L110F output. The next items of business are to grab 3d scans of both faces, model the adapter and mill one out. It'll be quite a large adapter plate, but it should still easily fit on my 4th axis (to reduce setups of course).

Update on impending progress 2/1/2024
I have found a shaft seal which should suffice for the L110F output shaft (seal around the OD of the female splined JF1A input shaft), though it is 1mm short and will sit recessed as much in the seal bore. The ID and OD match. The 710407 (Timken and National Oil Seals) is the only seal I could find which would work and I had to buy a couple on ebay, as they are backordered everywhere else I looked. I will update the forum on the shaft seal fitment when they arrive.
Seal Update again 7/11/2024. The 710407 did not work out. I tried a couple other shaft seals that also did not work out. I found one seal that is quite a tight fit (1mm too small on ID) but it does seal. Corteco 23121282458, for various BMW transmission output shafts. So far, that's the only off the shelf seal I've found that would work.

I am still actively working to design and mill out an adapter plate/block (am appropriate billet of 6061 or 7075 will likely be a few hundred dollars, as it will be about 2.5x12x12 to fit both flanges obout the centerline). The 3D scanning method of retrieving accurate critical dimensions has proven to be much more difficult than one would expect...

[Caddy2Spark]

This may be my solution for electrifying a Toyota Hilux Surf gen 3.

[TinkerTan]

My transfer case adapter solution is ongoing, but I have a scrappy cut and welded adapter basically completed. I cut the flanges off my A750F extension housing and off the torsen LF1A tcase (a perfectly good tcase from a $110k LS600...). I welded the flanges to make an adapter. Although I was careful about thermal expansion and warping while Aluminum MIG welding those, I ended up with an adapter too thin and with .030" parallelism across the width of the JF1A flange width: ~10inches. I will need to mill the faces of the adapter parallel then use a shim for now... but now I can move forward with mounting the transmission with transfer case in my truck and start building my inverter and trans harnesses, front transmission mounts, etc...

Regarding the shaft seals:
JF1A input shaft seal - kept OEM, did not need to change
L110F output shaft seal - a larger ID seal was necessary, since the JF1A shaft sealing surface has 51mm OD instead of 48mm. I could not find an exact fit shaft seal, but I found one that works well enough and is a tight enough fit in the L110F output shaft seal bore. It is the Cortico 23121282458, which is used in BMW trans output shafts. All others I tried that fit the shaft did not fit snugly in the bore and did not seal. This one is 1mm too small on the ID (50mm, the tcase shaft fits pretty tight). This is the best solution I could find that is not a custom seal (it would require a 62mm OD, 51mm ID, ~8mm height (although 9-10mm would only help it sit tight in the bore. There's like 15mm of bore height. The OEM seal does not sit all the way in the bore, it sits flush).

Although I set aside my 3D modeling and machining of the adapter to more quickly cut and weld an adapter together, I do plan to return to that soon, in order to end up with a stronger tcase adapter and to be able to provide you all with an adapter solution for 4WD with the L110F (with JF1A or JF3A).

[TinkerTan]

This week I drove my electric Tundra (4x4) up my driveway under its own power (in 2Lo, more context below). Soon I will return to machining a new adapter for the JF1A. I opted to blitz to get my truck drive 'able' instead of trying to do everything perfectly along the way.

As detailed in a previous post, I mounted a JF1A to my L110F by using a cut & welded adapter 'plate' (I salvaged and cut the LF1A and A750F) because I wasn't getting accurate enough 3D scan data to go ahead and machine one.
After that, I mounted/test-fitted the transmission in the truck and began working on the harnesses, which necessitated building brackets and mounting the key components (Inverter, Zombieverter, oil pump driver) for the purpose of establishing all the wire lengths...
Once I complete the harnesses and got the bulk of the electronics/wiring adapted to the tundra body harness (batt, ignition, start signals, body CAN, dash transmission display, etc...), I needed to alter the STM32-VCU firmware to support a lower cost smart shunt that is recently available.
Regarding the smart shunt FW, once I prove out this truck and finish the FW section for initializing the shunt (I configured my shunt using a CAN shield and terminal on a raspberry pi, not using zombieverter), I will push my FW in git so everyone can have a cheaper option than the $350 Isabellenhuette. This Riedon SSD shunt is under $200 shipped, has the same capabilities as ISA but only one voltage measurement (which I confirmed is fine because the STM32-VCU FW does NOT use the other two voltage measurements for precharge or otherwise).
Once I got my shunt working, I was able to get through precharge cycle and get the motors turning. I then found I needed to repair my oil pump controller because the cover was smashed (ebay seller), shorting it to ground internally. Luckily that worked.
After getting the motors and oil pump working, I fabricated a stainless (I want it to last, didn't want to paint, and I had stainless) mount for the flywheel/damper/torque limiting clutch assembly (I'm not welding the PSD or cutting the splines off my clutch/damper) and the front of the transmission. I mounted it to the OEM engine mounts.
After affixing the front of the transmission, I attempted to drive the truck up my driveway (I have a few percent grade) using my bench battery I've been using for these system tests... it is an EGO 56V 7.5Ah battery. I couldn't get enough current through my small gauge test wire (udcInv dropped below limit, Udc did not). I'll be redoing all my battery/contactor/precharge wiring when I install my full pack. To get by, I manually switched tcase into Low range (my ABS has a fault I need to resolve, so 4WD ECU doesn't respond, although I did rebuild the 4WD harness which was integrated into the engine harness that I butchered to build my other harnesses). With that additional reduction, with the L110F in Low gear, the truck was able to climb up my steep driveway with an EGO battery.
Update 6/10/2024:
Tcase actuators are removed because I have an ABS fault which seems to be preventing the 4WD ECU from attempting to actuate, and I needed Low range for my tests which are limited to about 10A with my test battery/wiring.
The front transmission mount is not complete but it's completed enough to test. I'll need to weld a few more stainless nuts for the flywheel and for the chassis mount flanges.
You may notice the L110F and L110 have different bell housing bolt patterns (GR vs UR blocks
I drove it about 50 feet in front of my house today but I have a 12V battery longevity issue, which limits that testing... I don't have a DC-DC converter set up or a HV battery to supply that yet.
The next priorities are getting set up with a larger battery pack, finishing the electronic control and wiring of my electric- hydraulic power steering pump and electric vacuum pump, then the A/C.

[LRBen]

I got the back of the GS450H measured via CMM this week. Has the bolt locations for 8 bolts, as well as the Z heights and also centered to the output shaft.

I have printed off a test piece and all the bolt patterns x-y are good, some of the z heights are not perfect it seems though. However it should be a decent start for anyone wanting to make up something to mount this to a transfer box.

[nkiernan]

I got the back of the GS450H measured via CMM this week. Has the bolt locations for 8 bolts, as well as the Z heights and also centered to the output shaft.

Thanks for sharing Interested to see your new LT230 approach

[TongueTester]

.....
Attached are my photos of the internals of the L110 / GS450h transmission tail housing (circa Jan 2021 - I didn't think to post them or check this thread at the time, sorry).

Thank you for this post. It is really helpful.

Do you have a similar set of photos for your L110f you can share?

I am particularly interested in the 'extension' section as I am trying to source this part from a friendly wrecker in Japan who wont ship the whole transmission (because he thinks it will leak fluid and get rejected by his carrier) - but he is willing to break it up for the parts I need.

Also wondering if you can confirm whether the 'extension' piece on the L110f between the gearbox and the transfer case houses all the same stuff as the tail section on the GS450h transmission? (eg Parking Pawl, Speed sensor, Planetary gear).

For context I am going for a Phev conversion using a GS450h as the donor.

Cheers

Peter

[robertwa]

Also wondering if you can confirm whether the 'extension' piece on the L110f between the gearbox and the transfer case houses all the same stuff as the tail section on the GS450h transmission? (eg Parking Pawl, Speed sensor, Planetary gear).

https://www.osti.gov/servlets/purl/947393

If you haven't seen it already, this white paper has some great photos of the transmission torn apart.

[TongueTester]

Hey Robert,

I have seen that report, but it doesn't quite capture the detail I was hoping for.

Its also nice to hear from someone who has had both apart.

I ended up pulling the trigger on an L110f from another (dodgier) supplier and also have a complete GS450h on the way. (My wife is so happy with me right now....)

I will revert back with the answer to my own question for the benefit of others.

Thanks

Peter

[TongueTester]

Hi guys,

An earlier post on this topic mentioned that the L110f transmission may bolt to an earlier model land cruiser transfer case.

They may be referring to the HF2A commonly found in Landcruiser 100/105 series which appears to have the same spline count on the input shaft as the transfer on the back of the L110f trans (19 spline shaft). With that said, a simple adaptor plate will almost definitely be required as the bolts / dowels do not align. I am hoping the method of connection will be the same as what Tinkertan had to do to connect his JF1A transfer case.

I will be attaching an L110f trans to an HF2A transfer case in the near future and will confirm with photos once I have a more definitive answer on this.

In the mean time - here is a shot of the back of an A442f Auto trans which mates to the HF2A transfer case in a 100 series landcruiser. The pic shows that the output shaft of the A442f trans appears to be the same as the output shaft on the 'extension' section of the L110f.

Note, the output shaft on the L110 (GS450H) with the tail section removed does not appear to have the same spline count and would not mate to a HF2A (refer images from previous posts above).

Hope this helps someone.

Cheers

Peter

[TinkerTan]

Thank you for this post. It is really helpful.

Do you have a similar set of photos for your L110f you can share?
...

Also wondering if you can confirm whether the 'extension' piece on the L110f between the gearbox and the transfer case houses all the same stuff as the tail section on the GS450h transmission? (eg Parking Pawl, Speed sensor, Planetary gear).
...

Cheers

Peter

I have not disassembled the extension housing of the L110F. I assume that the extension housing and final planetary gear set is swappable (implying that the output speed sensor and pawl line up) but I have not confirmed that. It's too bad the LS600h isn't more common... The housing could reasonably easily be machined, though not cheap. I think a billet would be $300+ and the GS450h planetary gear output shaft (to the drive flange/guibo) has a different spline. I'm thinking in terms of making it easier for more people to do such a swap/conversion with the used parts that are available.

[HerbP]

They may be referring to the HF2A commonly found in Landcruiser 100/105 series which appears to have the same spline count on the input shaft as the transfer on the back of the L110f trans (19 spline shaft). With that said, a simple adaptor plate will almost definitely be required as the bolts / dowels do not align. I am hoping the method of connection will be the same as what Tinkertan had to do to connect his JF1A transfer case.

I've been devouring information from the various threads around here for the past week as I'm thinking about doing an old clapped-out land cruiser EV conversion.

This thread caused me to register finally.

I have an HF1A case sitting in the barn which came from a 1991 JDM (rhd) HDJ81. I can take whatever measurements/photos that people need. One of my previous truck projects was to install a 1HD-T (6cyl turbo DI diesel) plus H151F (5spd) into a '93 FZJ-80 which had an HF2A case from the factory. The HF2A is a nice t-case with a center diff lock activated by a push button on the dash.

Happy to supply whatever info anyone needs from an HF1A.

[HerbP]

I will be attaching an L110f trans to an HF2A transfer case in the near future and will confirm with photos once I have a more definitive answer on this.

Just curious how far you got down this road?

I finally unearthed my HF1A case and introduced it to my L110f.

https://photos.app.goo.gl/TPJhsGkttbBnSQpf7

You wouldn't happen to have DXF's for an adapter plate would you?

[TongueTester]

Just curious how far you got down this road?

I finally unearthed my HF1A case and introduced it to my L110f.

....

You wouldn't happen to have DXF's for an adapter plate would you?

Hi Herb

Thanks for the video. Unfortunately, I am still a few months behind you so I can't help with a dxf file.

How did you find the mating of the shafts between the L110f output and the HF1A input spline?

i.e is the output shaft on the L110f long enough to make a good connection with the input spline of the T-case?

Cheers

[HerbP]

How did you find the mating of the shafts between the L110f output and the HF1A input spline?

i.e is the output shaft on the L110f long enough to make a good connection with the input spline of the T-case?

It looks like there's enough spline engagement if the face of the tcase is touching the face of the transmission. The seal surface sticking out of the tcase also slides perfectly into the seal on the transmission and looks like would even wear in the same place as it did when it was connected to an H55F. So I estimate roughly the same spline engagement as in the 3B use case (and 1HZ/H150F which is how I'd used it previously). My old 1HZ/H150F/HF2A combination with 4.10's, 35's and 27psi boost never had a problem.

I'll measure the actual spline engagement.

The real problem is that I think there's not enough room for an adapter plate while maintaining enough spline engagement.

Here's the two faces mated up. I haven't really clocked the transfer case relative to the transmission to check for driveshaft clearance

It looks like it might just clear those oil lines or whatever they are. (in all these photos, I have the tcase pulled away from the transmission around 3/4").

[HerbP]

I just did some more digging and learned some things. Apparently the HF1A came with a number of different input gears and the spline configuration is slightly different depending on whether it was originally behind an R151F or an H15xF. https://forum.ih8mud.com/threads/differ ... es.912806/

So just to confirm, this particular HF1A (in the above photos) came from the back of an H151F and it's these splines that match up with the L110F transmission. The HF2A which came behind the automatic transmission of an FZJ-80 should also have the same splines since that was the one I used behind my H150F. I hope that's just the right amount of confusion.

If your HF1A came from behind an R151F as seen in the Tundra apparently, the splines will not fit the L110F though according to the thread above, you could change the input gear to 36212-60120. YMMV.

[TongueTester]

Too Funny Herb,

After your post I went digging on the ih8mud forums and came to similar conclusions.

In the end I decided the transfers from an HDJ80, FZJ-80, FZJ-100 and FZJ105, HDJ-100 appear to have the bigger 19 spline and should (could) be suitable for use with the L110f, but as you say there are ways around it if your vehicle doesn't have the correct input spline (thanks Toyota).

In my particular case my transfer case is from a FZJ105 and appears to have the correct input spline based on a parts search (it has the same input shaft as the one you referenced above).

What are you thinking for an adaptor? Can we make it ~6mm thick and just omit a few bolts? Or are we going to be looking at a custom 'spud' shaft and extension piece? Or the even more ghetto option to cut and shut & weld the gearbox to the transfer? (I really hope not).

Keep us posted.

Peter

[HerbP]

What are you thinking for an adaptor? Can we make it ~6mm thick and just omit a few bolts? Or are we going to be looking at a custom 'spud' shaft and extension piece? Or the even more ghetto option to cut and shut & weld the gearbox to the transfer? (I really hope not).

I did a bit of a road trip yesterday so had some time to let my mind wander. I thought about buying that toyota tcase input gear, hacking off the yolk, and finding a dead transmission with the right output shaft. I think A442F's should be dimadozen, and as you say, making a spud shaft.

My LC friends (specifically the one named "Peter", coincidentally) were quick to suggest welding the L110F to the HF1A because really, how often was I going to be looking to change a tcase. I'm not sure what it is about the name "Peter" that leads to these solutions.

The other solution was to remove the last section of the L110F and machine down the face to make a bit of room to weld on an adapter plate to the back of it. We're already part of the way there because the seal in the L110F output sticks out past the transmission face by about 4mm already. I'm curious how difficult it would be to remove the last ("Ravigneaux") section of the L110F as in this photo:

If I stare at the cardboard cutouts I've made, we might be able to scab a thick aluminum plate onto the side of the transmission and get a few more bolts attached. The top two might be doable with some minor tcase mods.

I dunno. I'm not a huge fan of welding to oil impregnated cast aluminum. I know I could probably drive some oil out by putting the ravigneaux section in an oven for a while but on a scale of 0 to 6061.com, my TIG skills are in the low 3 digits.

Also, it's not a very repeatable project for others here. The spud shaft and a DXF file for a machinist turns this into a more repeatable swap.

I'm also not very far into my project. I still have a pig on the rotisserie. viewtopic.php?t=6293