5 speed auto (1 Viewer)

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I took a look at my a343 spare I have and have a few questions and thoughts

Is the main transmission of the a750 the same length as the a343? Will the hf2a transfer case from my 80 bolt up to the a750?

I should know these answers and I am sure I read them but just didn't retain it I guess.

Sounds a little crazy but looking at the transmission, I am wondering if I could slice off the back of the a343 bellhousing and the front of the a750 bellhousing, then tig the two together for an adapter? I have the means to get it done by a machinist and excellent welder to where the surfaces could be parallel milled after to make it all perfect.

Just a thought
 
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They said they kept the size and length the same.

I really think if this is going to happen it’s going to be a mud member who does like you are thinking, or makes an adapter plate and crank spacer to make the back of the 1FZ look like another Toyo motor.

Edit: I think the tranny has to be one from the 100 series, but I think the hf1a in the 100 and the hf2a we have are the same patterns. (Also, I may be wrong on the 100 being hf1a.)
 
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They said they kept the size and length the same.

I really think if this is going to happen it’s going to be a mud member who does like you are thinking, or makes an adapter plate and crank spacer to make the back of the 1FZ look like another Toyo motor.

I am researching doing this, except to make the back of the 1FZ look like the back of a Chevy motor. Toyota purity aside, the 6L80 is a much more suitable swap candidate for guys in the U.S.

Lots of donors, $900 controller to make it run behind anything, higher torque rating than A750 and better ratios for big tires: 4.03 1st, 1.15 4th ( making 4.10 gears effectively 4.71s while still having 2 overdrives to bring down rpms on highway).

The 6L80 is short enough that it’s possible to make it the same length as A343 even with adapter plates on front and back. (Although Marks 4wd adapter won’t work, too long; I have figured out how to make a 3.75” long tail housing with Novak adapters 6L80-Jeep/Dodge tail housing 3.25” and @NLXTACY NV4500 to HF2A adapter plate .5”.).

The 6L80 *might* have to be notched to clear the 1FZ starter. It has a removable bellhousing, buy a new one for $100. Making an “adapter” bellhousing is challenging, back of a 6L80 bellhousing looks like a valve body.

I have finish the basement before I can proceed with the 6L80 project, so it’s on the back burner. In the mean time I am hoping that Cruiser Brothers really does come through with A750 bellhousing and controller. I am worried about price, I heard WAT charges $12,000 to retrofit the 5 speed auto into DIESEL 80s (no custom bellhousing needed for 1HD-T).
 
Unfortunate this doesn't work for the 1FZ. Nice setup for sure.


It's too bad the A750F behind the UZ seems to be a different variant than what comes behind an FTE. Would be a relatively simple and economical upgrade for 1HZ/HD-T/HD-FT powered trucks in North America if the diesel trans was easier to source.

Still nice to have confirmation that an adapter-free solution exists.
 
I am researching doing this, except to make the back of the 1FZ look like the back of a Chevy motor. Toyota purity aside, the 6L80 is a much more suitable swap candidate for guys in the U.S.

Lots of donors, $900 controller to make it run behind anything, higher torque rating than A750 and better ratios for big tires: 4.03 1st, 1.15 4th ( making 4.10 gears effectively 4.71s while still having 2 overdrives to bring down rpms on highway).

The 6L80 is short enough that it’s possible to make it the same length as A343 even with adapter plates on front and back. (Although Marks 4wd adapter won’t work, too long; I have figured out how to make a 3.75” long tail housing with Novak adapters 6L80-Jeep/Dodge tail housing 3.25” and @NLXTACY NV4500 to HF2A adapter plate .5”.).

The 6L80 *might* have to be notched to clear the 1FZ starter. It has a removable bellhousing, buy a new one for $100. Making an “adapter” bellhousing is challenging, back of a 6L80 bellhousing looks like a valve body.

I have finish the basement before I can proceed with the 6L80 project, so it’s on the back burner. In the mean time I am hoping that Cruiser Brothers really does come through with A750 bellhousing and controller. I am worried about price, I heard WAT charges $12,000 to retrofit the 5 speed auto into DIESEL 80s (no custom bellhousing needed for 1HD-T).

No argument about that being a good transmission swap plan from me.

That said, do you think the Trans-Go shift kit for the a750/760 does as much good as the kit for the a343?
Cheap at $85
 
Edit ** Actually I went back and read the white paper and it says the new hydraulic control is all electronic, so line pressure is more a feature of the computer programming than the valve body. I guess maybe drilling out the valve body might contribute to the max line pressure though.

I would think so, according to the white paper I posted at the beginning of the thread says the A343 and A750 are a lot closer than they are different.

No argument about that being a good transmission swap plan from me.

That said, do you think the Trans-Go shift kit for the a750/760 does as much good as the kit for the a343?
Cheap at $85
 
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Ok so doing a little more research it sounds like it is exactly like I said in the last post. People have been drilling out the valve bodies to get higher line pressure, but the computer now is smart enough to see the higher pressure and it PWM to get the pressure back to stock levels. So to get the benefit of higher line pressure, more clamping force etc. It seems like you would need to do the shift kit as well as have a way to control the computer side. Which it sounds like maybe you can do with the Compushift pro.

No argument about that being a good transmission swap plan from me.

That said, do you think the Trans-Go shift kit for the a750/760 does as much good as the kit for the a343?
Cheap at $85
 
I am researching doing this, except to make the back of the 1FZ look like the back of a Chevy motor. Toyota purity aside, the 6L80 is a much more suitable swap candidate for guys in the U.S.

Lots of donors, $900 controller to make it run behind anything, higher torque rating than A750 and better ratios for big tires: 4.03 1st, 1.15 4th ( making 4.10 gears effectively 4.71s while still having 2 overdrives to bring down rpms on highway).

The 6L80 is short enough that it’s possible to make it the same length as A343 even with adapter plates on front and back. (Although Marks 4wd adapter won’t work, too long; I have figured out how to make a 3.75” long tail housing with Novak adapters 6L80-Jeep/Dodge tail housing 3.25” and @NLXTACY NV4500 to HF2A adapter plate .5”.).

The 6L80 *might* have to be notched to clear the 1FZ starter. It has a removable bellhousing, buy a new one for $100. Making an “adapter” bellhousing is challenging, back of a 6L80 bellhousing looks like a valve body.

I have finish the basement before I can proceed with the 6L80 project, so it’s on the back burner. In the mean time I am hoping that Cruiser Brothers really does come through with A750 bellhousing and controller. I am worried about price, I heard WAT charges $12,000 to retrofit the 5 speed auto into DIESEL 80s (no custom bellhousing needed for 1HD-T).

I think that’s one of issues with the 6l80 is the bellhousong is integral to the valve body. So it all has to come together.
 
Anyone out in Ohio near this place? Bills Auto Fabrication I imagine we still need some measuring and whatnot to confirm if a new bellhousing would be possible? But maybe Bill could craft the custom bellhousing hybrid from an a343 and a750?
The compushift pro says it supports the a750 tranny, though its unclear which signals it can fake and which ones it needs from the vehicle (and then of course which are available from the 1fz)
 
All the measurements have been done. you need a new bell housing. I have both sitting in my basement.
 
All the measurements have been done. you need a new bell housing. I have both sitting in my basement.

Awesome! So the input splines/torque converter all seem like they'd match up, just need a bellhousing crafted to mate the engine and tranny together with the appropriate thickness?
Edit: NM, went back and read page 9 for the details.
 
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You will need an adapter to mate the transfercase to the transmission. It will need to also house the additional clutch of the 650

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Awesome! So the input splines/torque converter all seem like they'd match up, just need a bellhousing crafted to mate the engine and tranny together with the appropriate thickness?
Edit: NM, went back and read page 9 for the details.
torque converter differences as well the engine to trans interface will all have to be custom. bell housing and flex plate adapter of some sort also.
 
I am researching doing this, except to make the back of the 1FZ look like the back of a Chevy motor. Toyota purity aside, the 6L80 is a much more suitable swap candidate for guys in the U.S.

Lots of donors, $900 controller to make it run behind anything, higher torque rating than A750 and better ratios for big tires: 4.03 1st, 1.15 4th ( making 4.10 gears effectively 4.71s while still having 2 overdrives to bring down rpms on highway).

The 6L80 is short enough that it’s possible to make it the same length as A343 even with adapter plates on front and back. (Although Marks 4wd adapter won’t work, too long; I have figured out how to make a 3.75” long tail housing with Novak adapters 6L80-Jeep/Dodge tail housing 3.25” and @NLXTACY NV4500 to HF2A adapter plate .5”.).

The 6L80 *might* have to be notched to clear the 1FZ starter. It has a removable bellhousing, buy a new one for $100. Making an “adapter” bellhousing is challenging, back of a 6L80 bellhousing looks like a valve body.

I have finish the basement before I can proceed with the 6L80 project, so it’s on the back burner. In the mean time I am hoping that Cruiser Brothers really does come through with A750 bellhousing and controller. I am worried about price, I heard WAT charges $12,000 to retrofit the 5 speed auto into DIESEL 80s (no custom bellhousing needed for 1HD-T).

I like the way you're thinking.

The 1FZ and 6L80 can be mated very easily. Just simply exchange the 1FZ for any LS/Vortec engine. Then 6L80 bolts right up.
 
I like the way you're thinking.

The 1FZ and 6L80 can be mated very easily. Just simply exchange the 1FZ for any LS/Vortec engine. Then 6L80 bolts right up.

Wa, wa, waaaaah
 
I was doing some light reading and came across something from Nostradamus that stated a 1fz-fe with a turbo and a750 transmission would make an LS swap obsolete.
 

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