Help in putting a 4-Speed trans in a 3 Speed frame (1 Viewer)

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Alex Waddell

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I am trying to stab my 4 speed transmission in my 1968 FJ40 (manufactured fall of 67') and the frame cross member seems to be too close.
I have been advised to do one of the following.
1. Pull the engine forward and install the transmission. Then install them both together.
2. Notch the cross member
3. Remove the cross member altogether.
Does anyone have experience with putting a 4-Speed in a 3-Speed frame and would like to give me some advice?
Thanks in advance.
 
It would probably be best to cut the crossmember out and re-weld it back a few inches after installing the transmission…if you are able to do that or know someone or shop that can do that for you…just my .02 cents.
 
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I did this a long time ago on my 72 40. I m pretty sure I didnt move or remove the tube crossmember. I think I removed the rear motor mounts and pivioted the back of the motor down. Swapped trans/tcases and jacked everthing back up. Have you looked in faqs & tech links in the same section? Theres a search function that works too.
 
One more question. While trying to fit the transmission I had the transmission angled up in the front and oil was dripping out of the rear output shaft. I just had this transmission rebuilt a a local shop. Is this normal or do I need to take it back to the shop?
 
I did this a long time ago on my 72 40. I m pretty sure I didnt move or remove the tube crossmember. I think I removed the rear motor mounts and pivioted the back of the motor down. Swapped trans/tcases and jacked everthing back up. Have you looked in faqs & tech links in the same section? Theres a search function that works too.
Good advice! Thanks!
I couldn't find anything directly about the cross member issue in my searches.
 
I removed the cross member when I did my transmission swap. I cut it cleanly out along the frame rails with the intent to reinstall it. But I never did and ended up scrapping it when I moved to a different state.
 
Installed a H42 into my 9/67 68 model back in 1994. I did not cut the crossmember or pull the engine. Used an old school transmission jack. Loosened the front the rubber isolators on the front motor mounts. Put a floor jack under the back of the oil pan. Then removed the rear motor mounts from the bellhousing. I then lowered the back of the engine. I was then able to instslled the transmission and transfer case to the bellhousing. Probably have to loosen the fan shroud. I did use a 74-78 transmission tunnel cover. Trimmed the back and had to rework the passenger side. But was able to use the four speed boots. Which lined up perfect.
 
I just did the same thing on my 1970. It was so frustrating. After hours, okay days of trying, I finally caved and asked my wife and son to help and presto, I got it in. Lower the rear of the motor and wiggle, a lot. I think I had the drum brake above the crossbar to slide it in. I scratched up everything along the way. After it was over, I do not plan on doing that again. You will need an enormous amount of patience and beer to calm the nerves, if you drink. Make sure the brake pads are new before you start. You will not be able to access afterwards.
 
Other options:

1> cut the crossmember off at both sides, rotate it to allow more clearance, sleeve and Re-weld.

2> Cut out 1/2” at both sides an inch out, bolt 2 1/4” plates together for each side, weld in two 1/4” plates on each side, unbolt for access, and bolt in when done.

I’d like to acknowledge mud for the source of these ideas… don’t know who… or where. Sorry.

Never done either personally.

Mark &/or ??
 
It will fit, but it will be tight. As mentioned by @Living in the Past and @pb4ugo you can loosen the motor mounts, loosen the fan shroud, support the rear of the engine and tilt it down to clear the cross member.

I would probably remove the tcase, install the transmission, tilt the engine/trans down and install the tcase.
 
I just did the same thing on my 1970. It was so frustrating. After hours, okay days of trying, I finally caved and asked my wife and son to help and presto, I got it in. Lower the rear of the motor and wiggle, a lot. I think I had the drum brake above the crossbar to slide it in. I scratched up everything along the way. After it was over, I do not plan on doing that again. You will need an enormous amount of patience and beer to calm the nerves, if you drink. Make sure the brake pads are new before you start. You will not be able to access afterwards.

What is ironic is I installed the four speed in the spring of 94. Summer of 94 bought a 73 FJ40 which came with a H42 and four speed bellhousing sitting in the back. Australia and other markets had a four speed in 73. Because of this adding a four speed to a 73 is just a matter of sourcing all the parts. No mods needed. I have since purchased 76 and 79. I am debating going back to a column shift three speed back into my 68. The rest of the drivetrain is still original. I had help when I did and having the proper transmission jack was were Hugh in doing the job.
 
Other options:

1> cut the crossmember off at both sides, rotate it to allow more clearance, sleeve and Re-weld.

2> Cut out 1/2” at both sides an inch out, bolt 2 1/4” plates together for each side, weld in two 1/4” plates on each side, unbolt for access, and bolt in when done.

I’d like to acknowledge mud for the source of these ideas… don’t know who… or where. Sorry.

Never done either personally.

Mark &/or ??


Not sure worth it rotating the torque tube. I have debating modifying the one on my 68. It I removed it would use one from a 9/72. Those are shaped different for better clearance around the brake drum. At one time I did compare the location of the two styles. The later style is a little further back.
 
What is ironic is I installed the four speed in the spring of 94. Summer of 94 bought a 73 FJ40 which came with a H42 and four speed bellhousing sitting in the back. Australia and other markets had a four speed in 73. Because of this adding a four speed to a 73 is just a matter of sourcing all the parts. No mods needed. I have since purchased 76 and 79. I am debating going back to a column shift three speed back into my 68. The rest of the drivetrain is still original. I had help when I did and having the proper transmission jack was were Hugh in doing the job.
Mark did a write up on 4 on the tree. I’d go that route before switching back to a three speed. I’ve always heard three speeds aren’t as strong as four.
 
I just did this with my 71 fj40.
What i did was loosen the engine and let it drop more than usual. But I also had blocks to make your not all the weight of the engine doesn’t rip the motor mounts.
I also used extra long screws and cut the ends off to make guides so that the trans lines up with the clutch. You screw them in to the bell housing side. It’s is going to take some jiggiling to get it to slip in. But it will eventually. Also make sure you cut at least a couple inches off the bottom of the floor reinforcement channel that is over the shifter on the transfer case. To give you room so the shifter doesn’t hit that section.
Once it’s in you can safely lift the tail section of the transfer case in place. And yes you won’t have any room to service the rear brake drum.
Unless later on you cut the cross member and re position it. Which I will do in the future.
Good luck
 
I just did this with my 71 fj40.
What i did was loosen the engine and let it drop more than usual. But I also had blocks to make your not all the weight of the engine doesn’t rip the motor mounts.
I also used extra long screws and cut the ends off to make guides so that the trans lines up with the clutch. You screw them in to the bell housing side. It’s is going to take some jiggiling to get it to slip in. But it will eventually. Also make sure you cut at least a couple inches off the bottom of the floor reinforcement channel that is over the shifter on the transfer case. To give you room so the shifter doesn’t hit that section.
Once it’s in you can safely lift the tail section of the transfer case in place. And yes you won’t have any room to service the rear brake drum.
Unless later on you cut the cross member and re position it. Which I will do in the future.
Good luck
Seems way easier to just cut the darn thing out from the get go and relocate rearwards while the drivetrain is out of the way.
 
I just did the same thing on my 1970. It was so frustrating. After hours, okay days of trying, I finally caved and asked my wife and son to help and presto, I got it in. Lower the rear of the motor and wiggle, a lot. I think I had the drum brake above the crossbar to slide it in. I scratched up everything along the way. After it was over, I do not plan on doing that again. You will need an enormous amount of patience and beer to calm the nerves, if you drink. Make sure the brake pads are new before you start. You will not be able to access afterwards.

D4C9BF61-B879-498D-925B-E6B5C3AED0CB.jpeg
 
I finally got the transmission in and thanks for everyone's advice.
It looks like I have about 1/2" between the cross member and the e-Brake but it will work.
I may cut the tube when I do the frame off which should give me more room.
But I am installing a 3F-E which has a bracket on the rear that does not allow me to tip the engine up much.
I ended up moving the engine forward to give me enough room.
The long alignment bolts that RodrigzCrzr suggested were very useful. Thanks!
 

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