Which T-Case: Vacuum or Mechanical? (1 Viewer)

[ki7xh]

Hi guys,

It's been a while since my last post. I'm in the process of restoring a 1985 Australian market HJ-75 Troopy. Just today, I finally got around to rolling the chassis out from underneath the body.

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I have a JDM 12H-T engine to replace the tired 2H diesel, and I'm wondering which transfer case I should use in the resto. I have the original fully mechanically shifted t-case, and I also have a vacuum-shifted front-drive t-case that came behind the H55F tranny and 12H-T package.

My gut feeling is "go mechanical". Having spent 20 years living off-road in Wyoming and relying on 4WD for getting to town, I'm skeptical of air/vacuum/electric 4WD. I've had the stuff fail at the worst of times, but never had a problem with fully manual/mechanical units.

However, if I understand it correctly, the vacuum-shifted t-case that's behind the 12H-T/H55F looks like it'll let me shift from 2Hi to N to 4Lo WITHOUT engaging the front drive.

Is that correct? If so, I like the idea of being able to go into low without having to spin the front prop shaft.

I'm also open to any comments about the vacuum system. Is it as reliable as the Land Cruiser / Toyota name would suggest?

Many thanks in advance for your thoughts.

Darrin in Wyoming

 

[hzjoe]

as long as your vac hose are not crack or dry vac is good but the only vac selenoid i saw problematic is in a corolla 4wd.h55f its a good tranny.if you shift to 4low the vac is engage automaticaly.good luck with your project.

 

[cambelt]

Id keep it mechanical , both work the same meaning you can shift from 4H to 2H on the fly but the front hubs must be engaged.
I have vacuum shifting and have never had a prob but 1 bad point if the front hubs are not locked in and someone that doesnt know how it works accidently presses the button the tranfer teeth grate badly .
The thing i like with the vacuum shifting is the switch is close to the steering wheel resulting in quick and easy engagement.
Dave

 

[Clint79]

you find posts of vac not engaging into 4wd but the only post you see on the manual shifting its the shifters sometime stiffen or sieze up but thats due to never getting used , by the sounds you will use it a bit so you wont get a seized shifter .. if your going to use it a bit you dont want a vacume fail
id go manual shift mate

 

[Radd Cruisers]

The vacuum shift won't fit into the narrow frame of an 45 series, but it would fit your 75 series. Personally, I like the mechanical shifter, and if you remove the shift gate you can pick any combo you want for Low and High range, 2WD or 4WD.

The vacuum shift mechanism itself is reliable, but the VSVs and tubing suffers with age.

~John

 

[roscoFJ73]

Ive had both and I dont have a real preference for either. However on a RHD model,the manual shifter sticks into your left calf muscle when in low range. Its a little bit annoying after a few hours.
Even when the vac shifter plays up its usually a hose has come off or have sprung a leak and it can be easily remedied in the field.

 

[Hulsty]

I have had two cruisers with VAC shift H55F, neither ever gave a problem and the button shift to HI 4WD was handy a few times.

I just converted my BJ74 from VAC to manual shift, main reason was for simplicity and outback toughness, though I have never had a problem.

In RHD config the shifter comes close to your left leg and I have knocked it out of 4wd a few times, getting used to it. Note that the floor plate covering the tranny is different on VAC and manual shift cars too.

 

[crushers]

well, it does fit John but it is real tight. BTDT.
if you have it out then swap just the front section of the t/case to the manual one. done. simple.
i run the vacumm on most of my vehicles and i do have issues and would prefer the manual shifter.

 

[Radd Cruisers]

well, it does fit John but it is real tight. BTDT.

When I put a 13BT and H55F into an FJ45 - no way was it going to fit and have clearance to move around. If things were off-set a little, maybe, but I was using all stock mounts and it was too tight.

The FJ45 frame is just that little bit narrower than the FJ40 / BJ4x frame that it didn't want to go.

I guess I could have used a bigger hammer, but then one my banana-levels would have been taken away from me.

~John
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