Topic: Non-us H41/1piece transfer to H55/split-case swap

[Deucey]

G'day guys

New to the forum, so hello to you all first   

I've got some questions.

Not long ago I've put a 3B (3.4 4pot diesel) from a LandCruiser into my Land Rover together with the H41 gearbox and 1piece transfer case. I've got 3.54 diffs.
This Landy is my expedition vehicle so not a high-spec rock crawler or anything.

I was wondering if I can swap my current transmission for a H55 with split case. I'm particularly curious if they are exactly the same physical size as the old unit as I don't fancy having to have my propshafts changed in lenght again..
I was hoping it to be a direct bolt on swap.

Oh, if I do I'm going for 4.7 diffs by the way to give me some good low range ratios and the 5th gear will give me a good highway gear.

At the moment with the 4speed and 3.54 it's struggling with hills. Swapping just the diffs to 4.7's makes to much of a difference, it'll be like driving a tractor (that's why I changed to 3.54 diffs in the first place).
By going to the H55 with 4.7's I get much better gear ratios and theoratically hills shouldn't be a problem anymore.

Here's a comparison:

TOYOTA H41 GEARBOX 1.96 transfer WITH 3.54 DIFFS   High range   Low range
first    : 4.925                                                  :17.43        :34.16
second   : 2.643                                               : 9.36      :18.34
third   : 1.519                                                 : 5.38        :10.54
fourth   : 1.000                                                : 3.54       : 6.94


H55 GEARBOX 2.276 split-case 4.7 diffs                            High range   Low range
First                                                      :22.76         :51.8
Second                                                   :12.31      :28.02
third                                                      : 7.13          :16.23
fourth                                                     : 4.7         :10.70
fifth                                                       : 3.97          :9.04       


Another thing....

My 1piece transfercase has the handbrake mechanism on the back of it. Can this be fitted to the split-case? In Australia I've worked on an FJ45 with 4speed and split case that had the handbrake on the tyransfercase so it should be possible.... Can I just swap the rear extension housing with the backing plate and all the other stuff?

And another thing...

Do the output flanges have the same bolt pattern? They probably do but it never hurts to ask the pro's here 


Many thanks for any input on this matter   

Cheers..
Koos

[crustybj60]

you will find all the info you need at www.ih8mud.com

i have seen a 3B, 5spd and split case in a mates 2A 109. he also ran the 60 series axles and brake set up as well. nice upgrade!

the 5spd is longer than the 4spd, you can fit a park brake to a split case, not cheap or easy.

flanges change from year to year.

cheers
crusty

[orangefj45]

that all depends........

the 5/85 and newer 4spds are the same length as the 5spds and use the same bolt pattern on the flanges. you will need the fine spline input version of the h55f or you can use the 10 spliner but you'll have to change the input gear.

georg @ valley hybrids

[the dude]

your H41 and one speed case are way shorter then the H55

The mounting bracket is also in a different location.

bolt flanges will be different.

The one piece split case drum e brake will not swap over.  There is a drum e brake available for the split case but it is $$$$$

I have both sitting on the floor if you need more info.