H55F Swap & 3-Speed to 4-Speed Clutch Upgrade Thread (3 Viewers)

[POPO AGIE]

I bet this will work just fine, as Kurt can vouch for below.

Does anyone have any experience running the propeller mount off the back of the split case?

I am pretty sure running the cross member under the H55 will require me to modify exhaust on the driver side, and a hard line running inside the frame rail on the passenger side. I’d rather leave both of those alone.

I don't know about that mount being used with the split transfer case but I met a guy in St Johns, OR that kept breaking the 4 speed transfer case housing with that mount. But he was also breaking bitfields because of the SBC 400 tuned to 400 hp may have had a lot to do with the breakage.

 

[POPO AGIE]

My 40 has been running the bellhousing mounts AND the cradle under the H55F for over 20 years. Zero issues and I’m still on my original mounts. I think it preserves all mounts including the front motor mounts. We did many 5 speed swaps into 40’s and 55’s with that method back in the day, I’ve never heard of an issue.

View attachment 3716428
Circa 2001 when I first installed the H55F

She’s still out and about on the road

View attachment 3716429

I just ordered new isolators and hardware. I am going to dig out the mounts and modify the DS so it will clear my adapter plate and get them bolted back on.

 

[Living in the Past]

My 40 has been running the bellhousing mounts AND the cradle under the H55F for over 20 years. Zero issues and I’m still on my original mounts. I think it preserves all mounts including the front motor mounts. We did many 5 speed swaps into 40’s and 55’s with that method back in the day, I’ve never heard of an issue.

View attachment 3716428
Circa 2001 when I first installed the H55F

She’s still out and about on the road

View attachment 3716429

Is there a reason why you didn't removed the motor mounts? Were these all OEM 40 series crossmembers? I am surprised you didn't source a 40 series top cover for the H55F. 2002 you were well ahead of the game as far as prices for the 40 series covers.

Do you feel the same about the propeller style used on the V8 conversions. Besides being more rigid it's further apart the isolators being sandwiched on the bellhousing and transfer case are more rigid. Never run a V8 not the idea of using six bolt in the back of the one piece aluminium transfer case would scare me. Vertical forces would be more likely to shear off. That location was designed for a PTO that would drive a pump is not the same as supporting the back half to the drivetrain.

 

[Pighead]

Do you feel the same about the propeller style used on the V8 conversions. Besides being more rigid it's further apart the isolators being sandwiched on the bellhousing and transfer case are more rigid. Never run a V8 not the idea of using six bolt in the back of the one piece aluminium transfer case would scare me. Vertical forces would be more likely to shear off. That location was designed for a PTO that would drive a pump is not the same as supporting the back half to the drivetrain.

I run a propeller type crossmember. But to a one-piece TC. And it's not a V-8. It was sorta a part of a "kit".
Back in 2001 or 2002, just a year or so after the very first Pig Run on the Rubicon, Morgan Fletcher, one of the founders of the LCML back in the early days before 'Mud was even a twinkle in Woody's eye, decided to put a hummer drivetrain in his Pig and therefore wanted to sell his doubler. I got it. Came with a SM465, a NP203 gear reduction box, some really rare Advance Adapter adapter and a one-piece Toyota TC, and a very custom tranny hump and a very custom skid plate and a propeller type crossmember. There were some big names involved in the design and assembly of this doubler and I trusted their advice and installed it all in my 55 in 2004 or so. The crossmember did crack and break once, 2006 or so, driver side right near where it bolts to the frame. Welded it up and it's been fine since. I do really flex the Pig now and then. I also run dual case savers on my TC, the usual top plate type and the Pardi case saver.

 

[peesalot]

IMO the weight of the h55 makes the cross member under it a good idea. I run the bell house mounts and the propeller mount on a 1 piece case like Pig no issues but you do have to set it up right and bushings/mounts need to be proper. I don;t know that it is nec to have the rear prop mount if you can get the cross member under the trans. I would ask Georg if he has a different approach but I imagine the set up Matt pictured is the way to go.

 

[cruiseroutfit]

Is there a reason why you didn't removed the motor mounts? Were these all OEM 40 series crossmembers? I am surprised you didn't source a 40 series top cover for the H55F. 2002 you were well ahead of the game as far as prices for the 40 series covers.

Are you asking why I didn't remove the bell-housing mounted mounts that are traditionally the "rear" mount on a 1-pc t-case? I don't see any reason not to run them in combination with a cradle mount under the H55F. More mounts don't add any vibration in my experience. Mine is a narrowed 6x Series cross-member with the frame side brackets utilized. We had pallets of them so they were much easier to source for a college kid (me) at the time

I was building a custom trans cover for this FJ40 with an integrated park brake handle and 6x Series trans tunnel cover & boots. As such the 40 Series top cover wasn't of much necessity to me. Many of the others we did in that time frame and since have used the rare 4x top cover but they were working with the factory trans cover (dog house), I wasn't.

Do you feel the same about the propeller style used on the V8 conversions. Besides being more rigid it's further apart the isolators being sandwiched on the bellhousing and transfer case are more rigid. Never run a V8 not the idea of using six bolt in the back of the one piece aluminium transfer case would scare me. Vertical forces would be more likely to shear off. That location was designed for a PTO that would drive a pump is not the same as supporting the back half to the drivetrain.

I'm not a huge fan of the propeller mounts personally. That said, maaaaaaaaaany 40 & 55 owners have been running them for decades with reasonable success. I have seen a cracked factory Toyota bellhousing that I believe is the result of all the "hanging" weight between the front mounts and the propeller mount.

 

[PabloCruise]

I run a propeller type crossmember. But to a one-piece TC. And it's not a V-8. It was sorta a part of a "kit".
Back in 2001 or 2002, just a year or so after the very first Pig Run on the Rubicon, Morgan Fletcher, one of the founders of the LCML back in the early days before 'Mud was even a twinkle in Woody's eye, decided to put a hummer drivetrain in his Pig and therefore wanted to sell his doubler. I got it. Came with a SM465, a NP203 gear reduction box, some really rare Advance Adapter adapter and a one-piece Toyota TC, and a very custom tranny hump and a very custom skid plate and a propeller type crossmember. There were some big names involved in the design and assembly of this doubler and I trusted their advice and installed it all in my 55 in 2004 or so. The crossmember did crack and break once, 2006 or so, driver side right near where it bolts to the frame. Welded it up and it's been fine since. I do really flex the Pig now and then. I also run dual case savers on my TC, the usual top plate type and the Pardi case saver.

View attachment 3717012

View attachment 3717013

View attachment 3717014

As far as I can tell, something like that!

 

[PabloCruise]

I found two 4-speed/2F flywheels.

Both flywheels have the same p/n on the non-working side, but the one labeled as from a '78 has a 3 next to a mountain symbol, while the other one has a 2 next to the mountain:

 

[PabloCruise]

Also fun: a clutch disc from a 3-speed clutch fits the 4-speed pressure plate perfectly.

I don't think there is any difference in surface area between the two.

 

[PabloCruise]

The clutch housing/pressure plate assembly for a 4-speed/2F is a spec shorter than the 3-speed/F version:

 

[PabloCruise]

I will get a pure side-by-side of the throw-out bearings and clutch hubs, but here are some pictures of each:

3-speed:

4-speed:

 

[PabloCruise]

I put some more info on the 4-speed clutch hub and throw-out bearings here:

Throw-out bearing install

Does the recessed part of the bearing go toward the hub, or does the flat side?

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