Connecting a GS450H to an existing Transfer Case?

[HerbP]

I took some measurements yesterday. In short:

• * There is 40mm of spline sticking out of the L110F from the seal surface
  * There is 20mm of no-spline at the front of the HF1A inside the protrusion of the seal surface.
  * The seal surface protrudes 14mm from the HF1A.
  * There is 4mm of protrusion of the face of the output seal on the L110F relative to the output mating surface.

I conclude there is around 34mm of spline engagement when the L110F is face to face with the HF1A and we have 4mm of room for an adapter plate plus whatever amount of spline engagement we're willing to sacrifice.

In this photo, I've placed a steel ruler across the mounting surface of the L110F to try to measure the amount of seal protrusion. I didn't take a picture of the measurement which is 4mm incl thickness of ruler.

The rest of the pictures:

More and more I'm swayed towards the spud shaft idea.

[HerbP]

The car that my L110F came from is still at the wrecker, half an hour away. I remember seeing the tcase sitting in the trunk. I think I might see how cheaply I can get that t-case so I can scavenge the input gear and hack off enough to make a spud shaft.. Looks like those tcases are going for sub-$200 CAD on eBay which is cheaper than a new HF1A input gear from Mr. Toyota.

[TongueTester]

Hey Herb,

Thanks for posting your WIP build thread - what a great project this will be once its finished & thanks for the measurements.

I can see from your measurements we don't have a lot of shaft to play with.... But like my wife keeps reassuring me, its not about size - its how you use it...

Could we get the output shaft of the L110f remade - but longer....
It doesn't solve the mating of the 2 together, but may buy enough 'meat' on the splines to allow for a straightforward adaptor plate.
This option is better than a spud shaft in my opinion because spud shafts are prone to alignment problems.

Another option might be to get the last cast aluminium section of the L110F remanufactured to suit our application.
i.e make the mounting face of the L110f 'shorter' so the output shaft sticks out further, re-position the output shaft seal to suit and give us the correct bolt pattern to mount the two together.

Or a combination of the two above. i.e get the output shaft remade longer, get a small section made to go between the end of the L110f and the T-Case.

I understand JLC offer metal 3d printing and CNC machining. Not sure if this would be within their capability but could be an option if we can get it into CAD. I may be able to assist with this (getting it into CAD) - depending on how much time you have as I have a 3D scanner.

https://jlccnc.com/

let me know your thoughts.

Peter

[HerbP]

Could we get the output shaft of the L110f remade - but longer....
It doesn't solve the mating of the 2 together, but may buy enough 'meat' on the splines to allow for a straightforward adaptor plate.
This option is better than a spud shaft in my opinion because spud shafts are prone to alignment problems.

let me know your thoughts.

My thoughts are scattered. My other friend Peter also has a 3D scanner. I think there's a lot to be learned by disassembling the case. Can only see so much in the osti.gov document.

I don't have much to report. My spring TODO list is interfering with my truck project. I did toss the whole kitten kaboodle on the engine hoist yesterday just to check for driveshaft clearance and actually measure the spline engagement. It's actually worse than I calculated. Only 25mm of actual spline engagement which shows that I don't know how to math.

In the second photo, I sprayed some machinists ink on the output shaft and slid the tcase as far as it would go. Then I worked the tcase back and forth to show me where the splines engaged. It's hard to see in the photo but the wear stops at 25mm. The last photo shows the 3mm that the seal surface of the L110F protrudes from the mounting surface.

From p51:

That looks like a complicated shaft to remake. That section of the case also contains the parking pawl mechanism so there'd be some complexity with recreating that in a 3D metal print.

We're so far above my paygrade now that I can't even conceive of it.

Milling down the mounting face of the ravigneaux section is seeming like a more plausible option now. Can we do what we need with an 8-10mm adapter plate? It was suggested by another friend that an 8mm steel adapter plate might be sufficient.

[TongueTester]

Hey Herb,

I agree that it is probably 'too hard' to remanufacture the Ravigneaux cast section due to the complexities in the casting (oil galleries etc).

I am not giving up on remanufacturing the output shaft just yet. In the photo you linked from the OSTI documentation it isnt clear whether the planet gear housing is integral to the shaft. The parking pall certainly just splines onto the output shaft as can be seen in the OSTI photos.
As soon as I work out how to separate the Ravigneaux section from the transmission I'll pull the output shaft to bits and post some photos (the Ravigneaux section is glued on like a bastard).

I estimate that the L110f transfer gets about 36mm of shaft engagement based on the measurements and summary below.

18mm from edge of transfer case input shaft to where the spline taper finishes
about 10mm from mating face to edge of transfer case input shaft

So milling down the Ravigneaux section and introducing an adapter plate should be viable in my opinion (based on 8mm steel adapter).

My preference is still to extend the output shaft due to my conversion being a PHEV (it will help me with firewall clearance).

[jrbe]

I agree, it looks like you could have 5mm machined off each case or maybe all off of just one case od then use a 10mm adapter between them. Flush head Allen / torx bolts could be used if needed.

You might be able to cut deeper if you use a radiused edge mill and leave the oil drain bosses in place. Then mill out a pocket for them in the adapter. But this may be unnecessary.

[HerbP]

I estimate that the L110f transfer gets about 36mm of shaft engagement based on the measurements and summary below.

18mm from edge of transfer case input shaft to where the spline taper finishes
about 10mm from mating face to edge of transfer case input shaft

We've already established that I'm bad at math.

But if I understand correctly, you're saying that the splines start 8mm further into the tcase than the mating face. I measured the shaft protrusion as 40mm plus 3mm from the face of the L110F. That's 43mm of shaft sticking into your tcase minus 8mm before the splines so that gives us 35mm of spline engagement to the end of the taper on the output shaft, so your estimate looks pretty good.

On my HF1A/L110F combo, I measured 25mm to the beginning of the taper on the output shaft. Measuring to the end of the taper on the output shaft, it's 29mm

So a 6mm difference.

If we rebuild the input shaft, we will need to lengthen the seal surface on the tcase so that it still engages with the seal in the L110F output section. We can probably get a speedi-sleeve to stick on there.

I'll wait to hear how you get the R section (I'm tired of typing that word) removed. I wonder if you're fighting with some dowel pins? On P.51 it looks like there are at least two. One on top and one on bottom.

[HerbP]

btw, here are some pictures I took the other day at the optimal clocking for my driveshaft which just barely clears the oil cooler line. The driveshaft clears better if I adjust the clocking so the driveshaft is higher but then my driveline angle might be pretty extreme and I might need a double cardan shaft. There might also be an opportunity to modify the oil cooler fitting but clocking the output much lower causes other fitment issues. I'll understand this better once I pickup my chassis.

The pictures gave me a bit of insight as to what an adapter plate might have to look like.