bj60 5 speed transmission swap with bj42

[cruiser10]

Well the title says it all. I have used these forums quite a bit for advice with my cruiser and know there are lots of knowledgeable people on here. Is it possible to take the 5 speed out of my bj60 and put it into my bj42 which currently has the 4 speed. Since i am a daily driver and that fifth gear would be nice for highway travel..
Thanks, Brett

 

[Leaping Deer]

Nope can't be done.

Welcome to Mud

Check out the search function and the FAQ.

I don't recall seeing a thread of someone with a B motor but I am sure that they have been done. Jsaltlic has one. Make sure you have the correct tranny as the input splines are different 2F/2H vs 3B if I am not mistaken. If both b motors you should be all set.

I am planning on doing this myself with my FJ45

One with an H motor https://forum.ih8mud.com/fj45-owners-club/198211-h55-split-case-into-hj47-troopy.html
One with a Chevy 350 https://forum.ih8mud.com/40-55-series-tech/188090-ram-jet-350-h55-install-73-fj40.html
I also liked the info in this thread. https://forum.ih8mud.com/40-55-series-tech/287420-ultimate-h55f-5spd-conversion-combo-2.html

Link to the FAQ with H55 info https://forum.ih8mud.com/40-55-series-tech/63334-h55-five-speed-into-40-55-a.html#post722719

 

[cruiser10]

Both trucks have the 3B motor in them does that mean i can do it without any other parts?

 

[dargreg]

Both trucks have the 3B motor in them does that mean i can do it without any other parts?

Yes just finished doing this exact swap.Use your mechanical linkage from the 4 speed for the transfere and get rid of the vacumn linkage.Mine were both split cases I asume yours are to.The trans mount is the same ,you may have to swap the output flanges or modify the crossmembers.Modify the hump a bit,other than that every thing slid right in.Oh I did the swap from the bellhouseing back.

 

[norm123]

to add to the same question cruiser10 was asking...can i use my bj42 original t-case? giving things a quick look i see there is a longer housing between the 5-speed and the t-case from the BJ60 (yr1985). Be it much smaller, there is a housing between the 4-speed and the t-case on the BJ42 (yr1981). i guess ill find out when i start tearing things down...with the housing differences, even if i had to use the t-case from the BJ60, it would be longer overall, meaning drive shaft lengths would have to change front and back. some input from someone who has done this would be greatly appreciated, or if someone could point me to a thread in the forum where this has been tackled.

 

[FF LC FREAK]

I swapped an H55 from a BJ60 into my BJ42, but I used the t/c that came with the H55. However, I don't recall there being a physical size difference between the 2 transfer cases. I believe the only difference is the idler shaft size. That shouldn't matter for the swap. I think what you are referring to is the 5th gear housing on the back of the H55. Think of the H55 as a 4 speed with a housing bolted on the rear for the 5th gear. It adds 4-5 inches to the length of the drivetrain. So, yes, you will need to have the rear drive shaft shortened and the front shaft lengthened.

 

[Living in the Past]

Believe the early split transfer case does not work with H55F. Has something to do about a oiler for fifth gear which is outside the main transmission housing.

 

[Diesel Cruiserman]

You can use all the split cases no matter idler or oiler (edit...early model cases did not have the oiler provisionhttps://forum.ih8mud.com/threads/some-h55f-and-split-case-tech.600279/page-3) ...4 speeds to five speeds you need to drill I believe another hole in the front half of the transfercase for another factory bolt and install plastic oiler..on the four speed case when bolting to a h55...

Factory US trucks 1985 and up had a spacer between trans and transfercase, on the early 4 speeds I believe they did not have the spacer making the trans shorter..

Beeeeeen along time since I had one of these apart..

Rob

 

[norm123]

thanks for the quick responses...i guess i was hoping by swapping t-cases, i could keep from changing drive-shaft lengths, but i see now even by swapping t-cases, i would still need to play with drive-shaft lengths anyway. my best bet would be to keep the t-case and do as FC LC Freak did. it's always a bigger job than one hopes!!! thanks guys