Fitting twin transfer cases

[MissDrew]

Been told this is a good write up so I thought I'd post it here. Personally I think it could be a bucket load better.

Anyway here are the pics of how to install twin transfer cases. I haven't yet finished, but have the front case and the adapter together ready for the rear case to be bolted up to them. Will do that part in the next coming weeks along with the full install in to my hilux.

This 5 speed case is my old one with the stuffed crawler gears in it. All I want from this case is the selectors for the front case and the low range housing as it has been ground out for crawler gears. By using this low range housing I will be able to fit crawler gears straight in it at a later date if I wish. The low range housing in the back ground I could have used but 3 of the 4 blot holes in the bottom are cracked so I decided against it.


Here is a pic of the Stuffed crawler gears, they were $1500 when I bought them and there was only 3 or 4 other sets around, so yes I had a good run with them.


Here is a 4 speed top shift case I had laying around, as you can see it has a bit of crap on it that needed to be semi cleaned first.


Cleaned and ready to pull apart


These pics are pulling the top shift case apart. The ONLY thing I want from this case is the shifters selector shafts and forks. Normally you would just get a complete top shift case and bolt it straight up to the back side of the adapter plate.


First you have to remove the rear output flange, this can be a prick but it has to be done. I didn't get a pic of doing that bit. Next you just undo the bolts around the rear section housing and lift it off. It may need some tapping with a hammer. This is what you are left with. Then just get some c clip pliers and remove this clip.


Then you just remove the next bit of housing and this is what you are left with.


Then lift the centre gear out. Which leaves the main shaft there on the left.


To remove stuff from the shaft you will need to lift the speedo gear etc up a bit. Then hold the top gear and let the others drop back down again as there is a ball under the speedo gear that needs to come out before you can lift every thing off the shaft.

[MissDrew]

Here is the gear and the ball I was talking about.


After then lifting as much as you can off the main shaft you can get to one of the shifter forks. Just use a punch and hammer and hit the dowl out of the fork so it will all come apart.


After removing the selector dog gear and such you are left with this gear, this gear then easily lifts off.


After lifting that gear off you can get to these 4 bolts and this c clip. You don't have to remove these but I find its all easier to handle if you do.


Once you have removed all that undo the remaining bolts around the last section of housing, there is only a couple of them left now. This is then what you will see once you open the low range section of the housing. Here we can finish removing the shifters selector shafts and forks.


All that work was to just get these few bits. The round dog gears aren't needed from this case as the 5 speed case I plan to put these forks etc in to has them all ready. Now why didn't I just bolt that complete top shift case up behind the adapter and use it in my hilux. Well I have 3 very good low usage t cases from behind 5 speeds here and I want to use them. So basically I'm turning one of them cases in to a top shift case.


I then did all that again to my old t case just to get its selectors and this part of the housing that holds all the low range gearing. You can see here where the inside of the housing has been grinded out to allow the fitting of crawler gears. Doing the extra work now to use this case will be well worth it in future if I ever decide to add crawler gears to the mix.


Here is all the stuff that comes with the twin transfer case adapter.

[MissDrew]

Now I needed a standard low range gear set from one of those cases I have. It just so happens that one of them cases is all ready in bits so I just walked over to the other side of my shed and picked up the gears. One of the gears needed is on the main output shaft. This gear is about the only gear that needs to be pressed off, just so happens I have a press hehe


I then got carried away with putting it all together and forgot to take pics grrr. But this is what it looks like before the housing and adapter are bolted together. You can see the new output shaft sitting in place with gears on it. Then the input shaft is sitting up on the housing, this drops in to the end of the output shaft, you need to put the low range selector from a FOWARD shift case (if your front case is also a top shift then you put top shift selector forks back in) on here as you drop it all together. The other gear sitting up next to the hole in the adapter just drops straight in to that hole/bearing.


and the finished product ready and waiting for the rear case to be bolted up hopefully tomorrow or Tuesday night. Problem is the other case is currently still in my hilux LOL. If you look at the shifters coming out the front you will notice I have welded them together. Normally you just weld a small bit of flat across the side of one fork (the one on the coke can side) and throw the other one out. However I have done it this way as I want to wire up a light on the dash that will tell me when the front case is in low range. By welding the other shifter shaft to the low range one I can still run the 4wd light switch in the front case. You can see the notch in the shaft and the hole where the switch bolts in.