Manual to Vacuum Shift early Splitcase conversion possible? (1 Viewer)

[EWheeler]

There are lots of details about swapping a late splitcase from vacuum shift to manual here in the 60 forum, but I haven't found anyone doing the reverse (yes, all will say with good reason no-one is doing that!). Without getting into an argument of why I should not consider this, I am curious if swapping an '83 split case from manual shift to vacuum shift is as easy as securing a good used vacuum shift housing/diaphragm/fork unit, and swapping it onto my early splitcase? I've not played with FJ60 parts before and have never seen the later model case vacuum shift housing other than in photos here on the forum.

I have an early FJ40 with vacuum actuated front output but am considering sliding a drivetrain in from an '83 FJ60, I would really like to keep the vacuum actuated front output lever and system in place. I know there are clearance issues to overcome with the passenger side frame rail if I move forward with this.

 

[cruisermatt]

you would have to drill and tap the four M8 holes on the front case half that the diaphragm bolts to. Then just plug the 4wd detent hole (threaded plug and thread sealer or just weld the hole shut).
All the hardware as well as the diaphragm assemblies are available new, 36410-60030, not cheap

I will have a extra vacuum front half I would trade you in a few weeks.

As for the clearance issues I wanted to do the exact same thing, it sounds like you know this but it is over an inch of frame rail that needs to come out, I was wanting to do the same on my 71

 

[EWheeler]

you would have to drill and tap the four M8 holes on the front case half that the diaphragm bolts to. Then just plug the 4wd detent hole (threaded plug and thread sealer or just weld the hole shut).
All the hardware as well as the diaphragm assemblies are available new, 36410-60030, not cheap

I will have a extra vacuum front half I would trade you in a few weeks.

As for the clearance issues I wanted to do the exact same thing, it sounds like you know this but it is over an inch of frame rail that needs to come out, I was wanting to do the same on my 71

Yeah, I need to weigh my options, I have a few. I've got a '78 h42 I could use, and that may be better as far as shifter cane location, then I just need to adapt it to my 3spd t-case. Saves fussing with driveshaft flanges/bolt patterns and such as well, just adjust d-shaft lengths. I'm swapping in late model FJ40 axles so I will now have parking brakes on rear axle which would allow me to get away with the splitcase. I really just do not want to put t-case shifter through the tunnel. I appreciate your input Matt, you've always got real world tech & experience to add to this place!

 

[SteveH]

This may not entirely help, but I installed a '65 vacuum shifter on a 1980 (non-split) FJ40 transfer case. Bolted right up. This went into a '65 FJ45 pickup and I didn't have significant clearance issues. So, the old shifter bolted up easily to this non-split case. I, too, wanted to preserve the dash shifter and not a cut a hole in the tunnel.

 

[EWheeler]

This may not entirely help, but I installed a '65 vacuum shifter on a 1980 (non-split) FJ40 transfer case. Bolted right up. This went into a '65 FJ45 pickup and I didn't have significant clearance issues. So, the old shifter bolted up easily to this non-split case. I, too, wanted to preserve the dash shifter and not a cut a hole in the tunnel.

This route crossed my mind, thanks for the feedback that it does indeed work. I'll have to look at this option.

 

[cruisermatt]

This route crossed my mind, thanks for the feedback that it does indeed work. I'll have to look at this option.

Yep, I used a vacuum diaphragm on a 4-speed single piece case case no problem, just had to lengthen the lower hi-low linkage a few inches to account for the longer transmission.

I ended up deciding splitcase wasn't worth it in my 71's current use (minimial)