H series box

mohawk · Jul 24, 2018

Ok , another question . The more I search the more confused i get.
I need too fit a B series input shaft into my spare h55F.. The box is a vaccume shift H / F series with 38mm idler ,so i guess its not that early.
I know there are 2 different bearing sizes for the B input shaft but what will i need too fit the box I have ?
Will one from a 4 speed be the same ? i may buy a whole box if i know it has the right input shaft.
Even if I knew what defenatly wont fit would make it easyer lol

nickolai · Jul 24, 2018

1984 bj42 h55f input shaft question

amauri said:
As long as we are dealing with the same gear tooth count (26t for H55f & 24t H42f), it is possible to install a late model input shaft into an early transmission. Also possible to go the other way around, early shaft into late model transmission.

I've attached some photos that hopefully will help make it easier to explain.

First off, what do we mean by early vs. late model transmission?
As already mentioned, late model can be recognized by the two ears you can see on the input shaft retainer cover, see photo #1.

Photo #2 shows the difference between late and early input shafts.
Mainly the wider bearing and the larger sealing surface.

Since it is becoming difficult to find the early shaft, I've successfully installed the late style shaft into early trannys by placing a hardened steel shim between the main bearing and the shaft.
Naturally, I used the old style bearing on the new style shaft, the shim just makes up the difference and positions the shaft in the right place to correctly mesh with the counter gear.

Late style bearing is 92 x 40 x 25.4
Old style bearing is 90 x 40 x 23

Looking a photo #3, you can see that there is also a difference in the OD where the seal is pressed into the retainer.
Late style retainer is 48mm
Early style retainer is 43mm

So the trick is to go to a bearing supply house and ask for a seal that has a 32mm ID and 43mm OD.

View attachment 845017

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mohawk · Jul 24, 2018

Thanks mate..i never found that one.

nickolai · Jul 24, 2018

mohawk said:
Thanks mate..i never found that one.

some h55f and split case tech

That's a goodie too

mohawk · Jul 25, 2018

yup , read it about 6 times

nickolai · Jul 25, 2018

This just closed - might get relisted

Fine Spline H55f 5spd

mohawk · Jul 25, 2018

Yea i saw that but im in hamilton so would be 800 bucks buy the time i got it.... i always have the one in the truck too..
I got my spare boxand transfer for 500 bucks and dont need it so ill just keep looking and asking for now.

mohawk · Jul 27, 2018

Any idea what i have here ?...i wonder if the box is early and someone has stuck a late bearing cover on front because it came with an early one and it looks odd the way it is.
Edit ... It is indeed a late box with 92mm bearing and a hole either side for the oil passages..The cover im not sure what it fits becase it looks too long ???
..It measures 35mm , That suits the b engines doesnt it ?