A442/A343 gas to diesel with original TCU

[69rambler]

The Cummins and Isuzu to FJZ80 adapters are finished. We are going to install the Cummins adapter for testing and an outside party is going to work with us to install the Isuzu 4BD1T/2t adapter.

The kits we make for the NV4500 and other Dodge transmissions are advertised on 4BTswaps.com in the Vendor section.

Right now the plan is to retain the factory TCU in the 94 W/A442 we have for testing. Some electronics connected between the TCU and transmission speed sensors that use input from the TPS and possibly a MAP sensor to manipulate the speed signals to the TCU.

 

[wrongway around]

why

if your into adapters you should make the rear tranny adapters for the tranfer case. cause these trannies cannot handle much more than stock torque and whp without some serious upgrades,at least with my limited experiences.

 

[69rambler]

if your into adapters you should make the rear tranny adapters for the tranfer case. cause these trannies cannot handle much more than stock torque and whp without some serious upgrades,at least with my limited experiences.

Great idea, as stated above WE ALREADY DO.

Allow me to completely change the purpose of this thread to explain a little from our perspective. With extensive diesel swap experience combined with transmission experience/knowledgeable engineering contacts and owning a manufacturing business my opinion is just different than yours.

I don't feel the Aisin automatics are any worse than what comes in a Dodge, behind a Cummins. When we use a 47RH or RE in an 80 series conversion the transmission related costs alone exceed the value of the entire gas Landcruiser. The fit into the Landcruiser is POOR. There is extensive modification necessary to install it. The transmission in a Landcruiser is quite literally built into the vehicle in more ways than other vehicles.

The Aisin 450-43LE is used EXTENSIVELY behind powerful diesel engines in medium duty truck applications. It is closely related to the Landcruiser transmissions.

Retaining the Aisin transmission, even if your power goals are pretty far out there and the transmission may need a plethora of upgrades to handle it it will still be cheaper up front and simpler from the install through wiring and maintenance.

Just my 2 cents fwii

 

[longbow]

Ok, for all you naysayers out there that think the Factory Aisin transmissions can't handle the torque of the diesels, rest assured that they certainly can! I have had my A440F tranny behind my Isuzu 4BD1T for a while now and believe me it is plenty strong enough. I have hammered this tranny hard and pulled mountain grades with loaded trailers and wheeled hard in the hills and it hasn't even tried to slip once. The tranny that I put in is a used one with 160K on it. The A440F / A442 are essentially the same transmission other than a slightly more efficient torque converter in the A442 and the fact that the later A442 is an electronically controlled tranny with solenoids on the valve body. It is essentially the same transmission that is used in the later Isuzu NPRs with the larger 175hp diesel engine and it is the A450 that 69Rambler mentioned earlier. There are many parts that interchange between these trannys and they are rugged and capable of constant use on 19,000GVW commercial trucks so I am confident they are plenty strong enough to handle the torque of a 4BT Cummins or the 4BD1/2T Isuzu engines. Toyota used the same tranny in medium size diesel buses in Japan.

By the way, my Isuzu is pumped up with a larger turbo pushing 20psi boost and the fuel turned up. I would estimate my HP to be 165 to 175. I just finished building my spare A440 that I bought and internally it is a very massive transmission! All clutches and steels for the both braking and gear lockups, no flimsy bands for braking like you see in the 700R4 or other wimpy US made trannys.

Anyway, I thought I would post up some real world experience for these trannys behind a diesel engine. I am in the process of installing my second Isuzu 4BD1T in my 76 FJ40 and I am going to use an A440F for that one as well.

Don

 

[SSSUPRA]

Don,

That seems to be some pretty good evidence for the strength of that trans. Can you or anybody else tell me whether the A343 is built similarly?

 

[longbow]

SSSUPRA

I have that tranny in my wife's 80 series and I have the rebuild manual for it that and I have gone through and it is a completely different tranny design than the earlier A440F/A442. It uses braking bands where the earlier trannys use clutch plates and steels for the braking and it is not as large a transmission either. I don't think it is a bad tranny at all, but I don't think I would put it behind the torque of a diesel engine.

If I had an 80 with that tranny I would buy 69Ramblers adapters and swap to an A442 transmission and a Compushift stand alone controller that way you can adjust the shift points and do electric torque converter lockup on command.

That is my .02 cents.

Don

 

[69rambler]

I feel like the 343 is a much better setup than the 700R4 and a lot of people are running those behind small diesels. If it can be made to behave properly behind a diesel it should live a good life.

Don and a few others have put the Aisins through some miles with diesels and there aren't any horror stories yet. I believe there is a 343 behind a 6.5 GM out there somewhere. Maybe they will see this and post up their findings.

 

[SSSUPRA]

There have to be at least a handful of A343's out there living behind turbo or s/c 4.5's, I wonder how well they're holding up? I imagine the conditions would be very similar to those behind many of these diesels.

 

[SSSUPRA]

So I've been doing a little bit of reading and stop me if I'm off base but it seems that the 4.5L is rated at 275ft/lbs and most road 4bt's are in the 265-340 ft/lb range unless they've been turned up. So is there any real concern of a stock or slightly turned up 4cyl diesel toasting these trans in the first place?

David

 

[longbow]

If you weren't going to tow anything real heavy and drove it like a stock 80 series, I would have no problem at all putting the A343 behind one of these diesels. I agree with 68Rambler that the A343 is a much better tranny than a 700R. I know they put it behind the 6.2 GM and there were never any major problems that I heard of. The 700R has some weaknesses but can be built up to handle 600HP with some moderate upgrades of components. That said, any of the Toyota trannies can be boosted in performance with some minor changes to the valve body and accumulators to make it shift firmer and have higher line pressure and increase flow to the cooler circuit. That is what I did with my Spare A440 that I just built to go behind my Isuzu in my 60. I haven't installed it yet because I am rebuilding my transfer case right now, but it is going to be installed in the next month or so.

If I recall correctly, the A442 uses a stand alone computer that gets input from throttle position sensor and speed sensor and maybe the cruise control circuit. It is a basic controller and doesn't need much input to make the tranny work right and that is why it can use an aftermarket controller like the Compushift. The A343 I believe uses a computer that also gets input from the ECU as well as the inputs listed above for the A442. That makes it more difficult to use as a swap tranny when there are no inputs from the ECU and engine sensors. At least that is how I understood the controls for those transmissions. If I am wrong, please someone chime in and let me know.

Thanks,

Don

 

[wrongway around]

my 2 bits had the 4.5 factory sc and toasted the 343 tranny, had the 4.2 diesel full hydro 442 toasted the tranny had the 4.5 electronic 442 toasted the tranny now ive got a 4.2 diesel and fighting to keep it alive ,i just had the torque converter totally tweeked with amazing results with slippage but still have a little higher than i like temps ,nobody wants to test tweek my v/b so i am biting the big one for an extreme v/b most likely, just so i can continue with other r&d with fuel and breathing mods. yes i abuse my trucks and drive 80% steep stop and go hills but my maintainance is double extreme . towing ha would not even remotely compare this to the big three, you can completely hype one of there tranies cheaper than you buy the bolt on stuff for the a442fs. my rebiult allison exchange from the factory for my international tow bus is 2500 bucks.so when you make the adapters for the other big three trannies to fit the 4.2 to h2fa put me on that wish list. sorry for the rant. ya im a bitter auto tranny guy, but gears are for bikes.

 

[69rambler]

my 2 bits had the 4.5 factory sc and toasted the 343 tranny, had the 4.2 diesel full hydro 442 toasted the tranny had the 4.5 electronic 442 toasted the tranny now ive got a 4.2 diesel and fighting to keep it alive ,i just had the torque converter totally tweeked with amazing results with slippage but still have a little higher than i like temps ,nobody wants to test tweek my v/b so i am biting the big one for an extreme v/b most likely, just so i can continue with other r&d with fuel and breathing mods. yes i abuse my trucks and drive 80% steep stop and go hills but my maintainance is double extreme . towing ha would not even remotely compare this to the big three, you can completely hype one of there tranies cheaper than you buy the bolt on stuff for the a442fs. my rebiult allison exchange from the factory for my international tow bus is 2500 bucks.so when you make the adapters for the other big three trannies to fit the 4.2 to h2fa put me on that wish list. sorry for the rant. ya im a bitter auto tranny guy, but gears are for bikes.

I can appreciate what you're saying. I don't mix well with automatics myself. My wife says one auto tranny mile with me driving is worth 100 miles for anyone else.

A great transmission isn't comprised of a bunch of billet anodized parts it's just put together by someone who knows exactly what they're doing and knows how to test it properly to ensure it's on the level.

 

[ClemsonCruiser]

Any updates on this??

I would like to put one of these in my '97 80 this coming winter.

Thanks!

 

[adventr]

Right now the plan is to retain the factory TCU in the 94 W/A442 we have for testing. Some electronics connected between the TCU and transmission speed sensors that use input from the TPS and possibly a MAP sensor to manipulate the speed signals to the TCU.

Can't believe I've missed this thread!


I'm highly interested in this. I've done a 6bt conversion on a GM a couple years back, and would like to do another one. As for the A442, my opinion is that it is better than the dodge 47rh/re transmissions, and it is MUCH better than a 700r4 or a dodge 518.

Seeing how the 93-94 cruisers have a separate TCM, should make them ideal for this kind of swap.

 

[69rambler]

Can't believe I've missed this thread!


I'm highly interested in this. I've done a 6bt conversion on a GM a couple years back, and would like to do another one. As for the A442, my opinion is that it is better than the dodge 47rh/re transmissions, and it is MUCH better than a 700r4 or a dodge 518.

Seeing how the 93-94 cruisers have a separate TCM, should make them ideal for this kind of swap.

There's more than a few who share your sentiments. The thread with pictures and details on these parts is here: Adapter kits for Isuzu to GM, Ford, Cruiser

Allmaras Machine
503-545-3731