bj40 with h55f gearbox and transfercase

[garic]

Hey guys just wondering whats involved with putting a 5 speed under a bj40? Has anyone done it? have heard that the h55f 5 speed will bolt straight up. Just wanting to know if any modifications are needed to x member mounts/ driveshaft and how hard it is. Any advice would be appreciated. Thanks

[muddy]

So long as you have the later model with the gearbox mount on the crossmember (as opposed to earlier with the bellhousing on the crossmember and the gearbox hanging free off the back), it will bolt up fine. BUT - the H55F is about 90mm longer - so the front driveshaft needs lengthening and the rear needs shortening. A rear spring flip (or 60 series rear springs) will move the rear axle back enough to keep the same rear driveshaft. Also - the input shafts are different between petrol and diesel, so if it's going behind a 3B, make sure the donor vehicle was diesel.

Edit: Forgot to mention - the gearstick and 4WD selector (and PTO selector if you have one) also come through the floor differently, so needs a bit of modification to the floor-pan...

[garic]

Thanks for your reply muddy, I think my truck has the gearbox hanging and the crossmember under the bell housing (is located just infront the joint between gearbox and bellhousing on bellhousing side). Im guessing that it is not strong enough to use standard x member under the bellhousing?

Has anyone done this conversion? Is it a mission to move the x member or make up a custom one?

The reason I ask this is because when im at 100k its revving like hell by my ears?? even though some calcs means it shud only be doing 2700 or so rpm. I only have 31s on it at the moment and was also thinking about just upping the size of the tires to bring the revvs down but then a lift etc would then come and it is also my daily driver. Its only a 1B series diesel but has an aftermarket turbo on it.

On another side how much rotational play should my drive train have? it doesnt have any up down left right but seems an excessive rotational play?

Thanks for your help.

[mickey]

it sounds like you have the older style transfer case which means you'll have to sort out the handbrake unless the hf55 has a transmission brake on the end of it. (some split transfercases had a transmission brake)

[muddy]

It looks like a fair bit of work (and therefore cost if you can't do it yourself) to get the H55F into your cruiser. The 5th gear is a 15% overdrive. Bigger tyres is another option, and so long as you keep them skinny to fit inside the rear guards, you should be able to run 33in tyres, but to get skinny ones you'll need 16in rims to get something like 285/75/16 or 275/85/16, since the 15in rim sizes are all 12.5in wide. Even with that, going from 31 to 33in tyres only gives around 5% diameter increase, or 12% if you go to 35's which would need some guard trimming or a lift. You may also be able to find some higher ratio diffs - They came out in the US with 3.7:1 diffs- but 4.1 is more common here.
Toyota advertised them new as good for long distance cruising at up to 80mph (on 31-32in tyres). Personally I wouldn't recommend it - but that's more to do with road handling and braking, although it would be sitting pretty close to 4000rpm at that speed. Cruising at 3000rpm is noisy and not very fuel efficient, but not likely to cause any engine damage. Bottom line - a 40 series cruiser is NOT an ideal vehicle for open road cruising.

[garic]

Cool thanks guys my main reason is doing 100ks an hour is because we use it to head up mt hutt which is just over an hour out of christchurch looks like I might just deal with 90ks an hour. A body lift will give me enough lift to put 33s on with 15inch rims yes? might head down that direction as it shud make it slightly happier off road also =)

[garic]

Does anyone know the best place to get the bits and pieces for a body raise? also there is no chance in getting a warrent with a SOA with no cert for it aye? Thanks guys

[muddy]

Unless you want to get into pretty serious offroading, I wouldn't recomment a SOA - it has a fair bit of cost attached, and then you get other issues like axle wrap, and instability. If you do it - you really want to go wider with 60 series axles. And definitely no way without certification. Body lift also needs certification, but if you don't mind cutting the rear guards higher, and maybe removing the lip on the front guards, you can fit 33's with no real problems, and no lift required.