H41 Upgrade in '71 FJ40 - Options (1 Viewer)

[Living in the Past]

I should've clarified that I would search for a 70 series FF rear with integrated parking brake.

I have both semi and full floating 40 series rear axles with parking brakes. The US never saw any full floating rear axles in a Land Cruiser until the 80 series. If you didn't want to keep the offset and 9.5" diff with the correct spring perch 8/80 semi floating 40 series axle is all that was available in the US.
Everything else has either been modified or imported used from another market. Only advantage I could see is some of the layer 70 series had disc brakes and parking brake. Width is close enough only need to move spring perches. Don't feel the need for rear disc brakes so full floating 40 series is the easiest option.

 

[4Cruisers]

I've decided to go with option 2 for the '71 FJ40, a split transfer case with drum parking brake. Buying an entire used transfer case to bolt up to my H41. Will sell my '82 split transfer case and my '78 FJ55 H42 4-speed/transfer case combination.

Axle options with integral parking brake didn't pan out, but from what I've read the best/easiest axle option would be a shortened FJ60 housing (due to apparently limited supply and expense of '81 and up FJ40 rear axles).

I think I was fortunate 15 years ago to find a very good used H41 from an older Land Cruiser for my '76 FJ40. I used the heavier flywheel, 3-finger clutch, and 3-speed transfer case from my '71 FJ40 to make the most of the H41. No luck in finding another older H41, so that option didn't pan out.

The Orion option would have been too expensive for the limited amount of off-road use the '71 FJ40 will get.

I appreciate all of the suggestions and input. The upgrade won't be started until next spring, but I'll add to this post when things get going. My goal is to take the '71 FJ40 to the second annual Solid Axle Summit next year.

 

[Living in the Past]

I've decided to go with option 2 for the '71 FJ40, a split transfer case with drum parking brake. Buying an entire used transfer case to bolt up to my H41. Will sell my '82 split transfer case and my '78 FJ55 H42 4-speed/transfer case combination.

Axle options with integral parking brake didn't pan out, but from what I've read the best/easiest axle option would be a shortened FJ60 housing (due to apparently limited supply and expense of '81 and up FJ40 rear axles).

I think I was fortunate 15 years ago to find a very good used H41 from an older Land Cruiser for my '76 FJ40. I used the heavier flywheel, 3-finger clutch, and 3-speed transfer case from my '71 FJ40 to make the most of the H41. No luck in finding another older H41, so that option didn't pan out.

The Orion option would have been too expensive for the limited amount of off-road use the '71 FJ40 will get.

I appreciate all of the suggestions and input. The upgrade won't be started until next spring, but I'll add to this post when things get going. My goal is to take the '71 FJ40 to the second annual Solid Axle Summit next year.

What are you currently running in your 71? If the original three speed my guess it's going to be a bigger project then you think. I like the later split split transfer case and plan on going with those on at least two of my pre 8/80 cruisers. One a 79 the other a 65 FJ45LP-B. Those will be pretty easy as far as the frame. Might go with one in a 73 FJ40 just because I'll have a extra setup. But a 71 has the earlier torque tube that is in the way. Just barely got away without moving it with a four speed and one piece transfer case in my 68. The split transfer case is a little longer. So not saying going this way is wrong just plan on the torque tube needing to be moved and floor clearance being a issue. Like I mentioned in PM I have a early H41 and I would consider selling but the tailshaft is worn and would not run it as is. Could get around that with the Fairey overdrive but clearance would be a issue with the torque tube otherwise would run that setup in my 68.

 

[4Cruisers]

What are you currently running in your 71? If the original three speed my guess it's going to be a bigger project then you think. I like the later split split transfer case and plan on going with those on at least two of my pre 8/80 cruisers. One a 79 the other a 65 FJ45LP-B. Those will be pretty easy as far as the frame. Might go with one in a 73 FJ40 just because I'll have a extra setup. But a 71 has the earlier torque tube that is in the way. Just barely got away without moving it with a four speed and one piece transfer case in my 68. The split transfer case is a little longer. So not saying going this way is wrong just plan on the torque tube needing to be moved and floor clearance being a issue. Like I mentioned in PM I have a early H41 and I would consider selling but the tailshaft is worn and would not run it as is. Could get around that with the Fairey overdrive but clearance would be a issue with the torque tube otherwise would run that setup in my 68.

The '71 is already set up with a '76 2F, H42 4-speed with one-piece transfer case from a '78 FJ55, and driveshafts from an early 4-speed FJ40. Like your '68 I just barely cleared the torque tube, so I know I'll have to deal with that. I'll more than likely have to change the length of the rear driveshaft, and look at the front driveshaft as well. Same with the bolt pattern on the split case front output flange and parking brake drum, but those are easy to work around. Nothing I can't tackle.

Do you know if the split case H41 will bolt up the the mid-'70s 4-speed bellhousing in the '71 (the bellhousing with the rear engine mounts)? If so, do I still need a later FJ40 transmission crossmember?

 

[Living in the Past]

The '71 is already set up with a '76 2F, H42 4-speed with one-piece transfer case from a '78 FJ55, and driveshafts from an early 4-speed FJ40. Like your '68 I just barely cleared the torque tube, so I know I'll have to deal with that. I'll more than likely have to change the length of the rear driveshaft, and look at the front driveshaft as well. Same with the bolt pattern on the split case front output flange and parking brake drum, but those are easy to work around. Nothing I can't tackle.

Do you know if the split case H41 will bolt up the the mid-'70s 4-speed bellhousing in the '71 (the bellhousing with the rear engine mounts)? If so, do I still need a later FJ40 transmission crossmember?

Look at the thread on a H55F going into a 74. Using the stock early four speed bellhousing and motor mount mounts. That has a hand break on the T case so yours will be lighter. It was mentioned this will not be used as rock crawler though. Since I've collected a number of crossmember piece that's the route I'll. Just need to located some early eighties spacers for the clutch slave cylinder. Believe those still used the larger bolts the motor mounts used.

 

[Cruiserdrew]

Do you know if the split case H41 will bolt up the the mid-'70s 4-speed bellhousing in the '71 (the bellhousing with the rear engine mounts)? If so, do I still need a later FJ40 transmission crossmember?

It will bolt up just fine.

But, the transmission mount will be stronger than the bellhousing mount. Just simple physics. And the bolt holes to mount the transmission are likely already there. If so, I'd use them, and build a cross member. The Toyota motor mount for this application makes the crossmember an easy job. Then only the transfer case is "floating".

Similarly the torque tube is not a big deal. Cut it off flush with the frame and remount on scab plates a few inches to the rear. Ideally far enough back so the drive train assembly could be pulled without removing the parking brake drum. Your future self will thank you for that.

 

[Living in the Past]

It will bolt up just fine.

But, the transmission mount will be stronger than the bellhousing mount. Just simple physics. And the bolt holes to mount the transmission are likely already there. If so, I'd use them, and build a cross member. The Toyota motor mount for this application makes the crossmember an easy job. Then only the transfer case is "floating".

Similarly the torque tube is not a big deal. Cut it off flush with the frame and remount on scab plates a few inches to the rear. Ideally far enough back so the drive train assembly could be pulled without removing the parking brake drum. Your future self will thank you for that.

Not a big deal if you have a welder which I don't. Personally would just weld the torque tube to plates and bolt the plates to the frame and just remove then rather then weld underneath the vehicle. A lift is another thing I don't have. From when Toyota starting putting in a floor shift until 79 changing the clutch was a pain. Pulling the transmission cover is enough work. Have no choice unless you can just lower it so the shift tower clears the hole in the tunnel cover. Never thought about it but installing a H55F with a 60/70 series top plate probably have no choice to lower it unless they cut the opening further back.

 

[4Cruisers]

Look at the thread on a H55F going into a 74. Using the stock early four speed bellhousing and motor mount mounts. That has a hand break on the T case so yours will be lighter. It was mentioned this will not be used as rock crawler though. Since I've collected a number of crossmember piece that's the route I'll. Just need to located some early eighties spacers for the clutch slave cylinder. Believe those still used the larger bolts the motor mounts used.

It will bolt up just fine.

But, the transmission mount will be stronger than the bellhousing mount. Just simple physics. And the bolt holes to mount the transmission are likely already there. If so, I'd use them, and build a cross member. The Toyota motor mount for this application makes the crossmember an easy job. Then only the transfer case is "floating".

Similarly the torque tube is not a big deal. Cut it off flush with the frame and remount on scab plates a few inches to the rear. Ideally far enough back so the drive train assembly could be pulled without removing the parking brake drum. Your future self will thank you for that.

Thanks guys! I just finished looking through @Poser's 2007 thread on installing an H55f into a'79 FJ40. I haven't measured the front bearing retainer on my late H41 and compared it to that on my new H55f, so I don't know for sure whether or not I'd have to clearance the earlier bellhousing. Something tells me the H41 and H55f are the same. I'll also look at the thread on the same installation in a '74.

As far as the torque tube on the '71, it turns out I'll have an EXTRA 1/4" of clearance if I install the '84 H41 into the '71, even with the split transfer case parking brake drum . The overall length of the early H42 with one-piece transfer case from the rear face of the bellhousing to the face of the parking brake drum is ~1'-9-5/8", as measured on my '76 FJ40. The same measurements would apply to my '71 FJ40 (which I can't get to right now because it's at our place in Nevada). The overall length of the late H41 with split transfer case is ~1'-9-1/8". Also, the distance from the rear face of the bellhousing (measuring rearwards) to the face of the front output flange is ~4-1/4" for any of the combinations. That would mean no changes in driveshaft lengths would be required, I would just need to get later slip yokes front and rear (if necessary) to match the parking brake drum and front output flange, or some other easy solution (flange with universal hole patterns?). I'm not sure, but is the mid-'70s parking brake drum currently on my '71 FJ40 ('78 FJ55 one-piece transfer case) compatible with the split transfer case rear output shaft (splines, etc.)?

I might be comfortable with the later combination hanging from the earlier 4-speed bellhousing. If not, I could easily belt-and-suspenders it with a lighter duty transmission crossmember by modifying the spare transmission crossmember I have on my '89 FJ62 donor vehicle.

This project is potentially turning out to be even easier and cheaper than I thought.

 

[Living in the Past]

Easy to tell the difference in the front seal retainer. Later will handle two channels for getting oil to the front of the bearing. This happen 10/85 on all four and five speeds I believe. So depends on when your H41 was made wether you will need to grind the clearance. Pretty sure Steve (Poser) used a new transmission.

 

[4Cruisers]

Thanks. My H41 is from an '84 HJ47. Too bad the transfer case had been replaced with an '82 non-parking brake case (assuming that's how the HJ47s were set up).

 

[Poser]

You will not need to modify the flywheel housing to make the H41 fit a four speed flywheel housing.

 

[4Cruisers]

Thanks, that's good to know. The project is looking easier all the time. I'll be getting some relevant practice in the next week or so, I'm getting ready to build my '89 FJ62 split transfer case (converted to manual front drive engagement) onto my new H55f, then installing it behind my 3FE and 3F bellhousing.

 

[Living in the Past]

You will not need to modify the flywheel housing to make the H41 fit a four speed flywheel housing.

So it was just the H55F that the nose cone/seal retainer changed on 10/85 that had clearance issue not the four speed?

 

[Living in the Past]

Thanks. My H41 is from an '84 HJ47. Too bad the transfer case had been replaced with an '82 non-parking brake case (assuming that's how the HJ47s were set up).

More than likely it had a hand brake. My 84 HJ47RV H41 had the hand brake. Did some searching it was rare to find any LWB 4x series with hand brake on the rear axle.

Wouldn't be for a while until back to where most my parts are stored. By then hopefully will have my parts from a BJ42 including the crossmember for a five speed. At some point will be able to compare it to one for a post 8/80 FJ40 four speed. My guess it's the same. Can also compare it to the one from a FJ62. Guessing the FJ62 is wider. Still figuring out a odd ball crossmember that the center section is same as my other 4X series but the L brackets are shorter.
I'm sure you know the FJ62 crossmember attached to the adapter behind the transmission and in front of the transfer case? Since your not going to do this until spring should be able to help figure how close the FJ62 crossmember is to the 40 series. Besides the 40 series the early 60 series had removable L brackets. Sometimes wonder if my odd ball has a 40 series center section and 60 series L brackets.

 

[4Cruisers]

I'll have to check my two '84 FJ60s at my place in Nevada to take a closer look at the crossmembers and see if they have the removable L brackets. Would be great if you could help me compare the various crossmembers. Looking forward to getting this project off the ground next spring.

 

[Living in the Past]

I'll have to check my two '84 FJ60s at my place in Nevada to take a closer look at the crossmembers and see if they have the removable L brackets. Would be great if you could help me compare the various crossmembers. Looking forward to getting this project off the ground next spring.

I'm sure by spring time can help get this figured out. Curious how the 62 center section compares to the 40 section. The HJ47 L brackets were completely different then the FJ40. I'm sure you know how it's a pain in the a$$ have stuff at different locations. Think my HJ47 crossmember is here since my FJ45 is here also. Everything else is in the Phoenix area. Brought it up to see how it would fit a early 45 frame. Which it did. At one time planned on a 3FE/A440F/ split transfer case in my 45 which is why I picked up the FJ62 crossmember. Plans have changed many times on the direction I was going. Think I have the running gear figured out. The cab is another matter.

 

[4Cruisers]

I just pulled the seal on the front output shaft of my '89 FJ62 transfer case and found the oil slinger (36119-60030, RECEIVER, TRANSFER OIL, NO.2) that rides on the splined shaft between the seal and the bearing. The older split transfer cases did not have this. Would it be beneficial to install one of the slingers on my parking brake split case for my '71 FJ40 upgrade? Or is it not really necessary? It doesn't look like it would interfere with anything.

 

[4Cruisers]

As I'm getting ready to install the modified FJ62 split transfer case on the H55f for my '86 FJ60 build I'm thinking of what's needed versus what else could be done "while I'm in there" on the '71 FJ40 upgrade. The way the parking brake drum split case is packaged for shipping the least I need to do is to pull the rear case half from the case that's currently behind the H41, remove the fewest number of parts, slip in the output shaft/gears, replace the rear extension housing/companion flange with the parking brake extension housing/parking brake assembly, and install the old rear case half.

I'm pretty sure both cases have the 34mm idler shaft and comparable parts throughout the assembly, but will know for sure when the USPS delivers the packages with the new case later this afternoon. The old case has a date code of 2F0320, so it was built in 06/82. Because it's earlier than 10/82 the front case half shouldn't have provisions for the 5th gear oiler cup. If the front case half on the new case does have the 5th gear oiler cup provision I'll keep both halves of the new case to sell later here on MUD, along with everything else needed to build a complete non-drum parking brake split case. The later case with the 5th gear oiler provisions would be more useful to someone else because it could be used for H41s, H42s, or H55fs. Mine will stay on the H41, at least for as long as I'm around.

So it looks like the best thing to do for the '71 FJ40 upgrade would be to remove, clean, and reinstall all components from the new case, along with the later improved transmission output shaft seal, using the old split case halves and the appropriate gasket kit. The rest would be available to sell here on MUD.

 

[4Cruisers]

UPDATE: The new case has a date code of 4J3175, so it was built in 10/84, has a 34mm idler shaft, and has provisions for the 5th gear oiler cup. It does not have the "extra" hole in the front case half that needs to be plugged for installing it behind an H55f. The transfer case came off a BJ45 4-speed, maybe those diesel transmissions have a different rear bolt pattern. I thought all split cases of this vintage had that extra hole. So I'll be selling the new case halves along with the old internals later here on MUD.

 

[4Cruisers]

I'm thinking of setting up the clutch the same as on my '76 FJ40, which has an early H41 mated to a 3-speed transfer case. For the '76 I used an F flywheel and 3-finger clutch pressure plate (the clutch disc is common between the F and 2F clutch assemblies), along with the matching clutch fork and throwout bearing. I know I have a good 3-finger clutch, and maybe the heavier flywheel, but don't know for sure if this set-up would be compatible with my '84 HJ47 H41. I'm pretty sure it will work, but can someone confirm?