Toyota FJ40 1976 - 3 Speed to 4 Speed Transmission

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Hi everyone!

I am new at this Forum so i hope i post this in the right place!

i am the rightfull owner of a 1976 FJ40. This FJ has a 3 speed transmission. Today i bought a 4 speed transmission and i want to know what parts i need to put it on my car. I red somewere on this forum that i only need a 4 speed bellhousing?

i red somewhere else that i also need new drive shafts?

As you can read, i need some help here and someone told me this is the best place to geather some information!!

i hope you guys can help me out!

Kind regards,

FJBaker from Curacao
 
Joined
Apr 2, 2008
Messages
10,150
Location
Victoria, BC
Bel-housing
Driveshafts x2
Modification to holes in floor

Frame crossmember clearance close ??? - in
North American rigs ‘76 would come with a four speed so it’s hard to say where the pipe behind yours will be located.

possibly swapping flanges on transfer case and/or diffs to match drive shafts.

what year of 4-speed? T-case attached? Or do you want to mount your 3-speed T-case to it?

May need T-case input gear if reusing your T-case.

Normally a 3-speed clutch would be a three finger clutch, but it would work with a 4-speed… some prefer it since it has a heavier flywheel. Diaphragm clutch will also work. Consider replacing if you don’t know it’s age… it’s a lot easier while the transmission is already out.
 
Joined
Sep 2, 2021
Messages
3
Location
Curacao
Bel-housing
Driveshafts x2
Modification to holes in floor

Frame crossmember clearance close ??? - in
North American rigs ‘76 would come with a four speed so it’s hard to say where the pipe behind yours will be located.

possibly swapping flanges on transfer case and/or diffs to match drive shafts.

what year of 4-speed? T-case attached? Or do you want to mount your 3-speed T-case to it?

May need T-case input gear if reusing your T-case.

Normally a 3-speed clutch would be a three finger clutch, but it would work with a 4-speed… some prefer it since it has a heavier flywheel. Diaphragm clutch will also work. Consider replacing if you don’t know it’s age… it’s a lot easier while the transmission is already out.
Aah great! I have to search for the drivelines then, and the bel-housing!

it is a Colombian FJ, i think they were standard with a 3 speed in that time. The 4 speed i have has a T-case attached to it. The 4 speed is somewere from 76/77/78/79, but it is overhauled a few years ago.

i will look for the Diaphragm clutch! I think its best to do it right!

Thanks!!
 
Joined
Apr 21, 2005
Messages
20,590
Bel-housing
Driveshafts x2
Modification to holes in floor

Frame crossmember clearance close ??? - in
North American rigs ‘76 would come with a four speed so it’s hard to say where the pipe behind yours will be located.

possibly swapping flanges on transfer case and/or diffs to match drive shafts.

what year of 4-speed? T-case attached? Or do you want to mount your 3-speed T-case to it?

May need T-case input gear if reusing your T-case.

Normally a 3-speed clutch would be a three finger clutch, but it would work with a 4-speed… some prefer it since it has a heavier flywheel. Diaphragm clutch will also work. Consider replacing if you don’t know it’s age… it’s a lot easier while the transmission is already out.


9/72 the frame and tubs all changed accommodate a four speed. Australia had a four speed starting 9/72. Possible other markets. The frame and tub will need no modifications. Transfer boot is most likely already the same as the four speed. Hole for the transmission is smaller and slightly different locations. Transfer case needs the input gear and everything behind it on the transmission tailshaft from a four speed. Someone with a 76 is currently doing the same thing with one from South America.
 
Joined
Apr 21, 2005
Messages
20,590
The flywheel, pressure.ate and clutch was not a three speed verses four speed. It was just a date change. You should have the lighter flywheel and diaphragm pressure plate already.
 
Joined
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Victoria, BC
Nothing wrong with a three finger clutch. They work great… I’ve read they are a little more positive engagement, but never had any issues with mine. Just avoid reman clutches.

you’ll need a diaphragm: flywheel, throw out bearing, clutch fork, and pivot if you convert to a diaphragm type clutch. Vs just replacing the clutch disc, pressure plate, and bearing.

The heavier flywheel is good for low speed driving and crawling. Not a bad thing in a tractor.
 
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Aahh so i dont need the clutch plates?

does anyone know how long the driveshaft need to be for a 4 speed? Or is this different with every year?
 
Joined
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Messages
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The flywheel, pressure.ate and clutch was not a three speed verses four speed. It was just a date change. You should have the lighter flywheel and diaphragm pressure plate already.
I wasn’t sure how that worked. My July 74 had a three finger clutch with a four speed transmission… so I’m aware it wasn’t specific to the change in transmission (even though I’ve often seen it referred to that way).
 
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Messages
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Aahh so i dont need the clutch plates?

does anyone know how long the driveshaft need to be for a 4 speed? Or is this different with every year?
If in doubt about their condition I’d machine the flywheel and replace the clutch disc, pressure plate, and throw out bearing… just to avoid having to pull the transmission later to do it.

Just as I’d replace the oil pan gasket & rear main seal if they are old and weeping… to avoid pulling the transmission later to do it.

That said, I reused my 21 year old clutch when my first 350 died… because I knew it was still good, I’m not hard on it, and I knew the history. It was somewhat of a risk, but I didn’t want to spend the extra time & money when I knew it would last me another 10+ years.

Driveshaft length will be good from any rig with the same transmission and t-case. If your t-case has an E-brake just get driveshafts from a 40 with a four speed and E-brake. Preferably with the same flange bolt spacing to avoid needing to change or modify them, but flanges are cheaper than driveshafts and easier to find.

BTW, your fully Compressed driveshaft should be about 1” shorter than the space it needs to fit in. (If that makes any sense… 1” to allow for drivetrain movement).
 

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