12-ht to autobox of some kind ! !

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I've got a Hj61 with the all mighty 12-ht and H55 .
For some reason i am getting old " Dooh" :bang: and don't want to drive with a stick and heavy clutch .

My Q , what should i use ? and what can/will fit.
Th 700 ? cause they are cheaper
Th 400 cause they can handle it.
Toyota auto ?
And most important adapters, custom make it or are there some all ready made for this.

Notice that i am from Denmark and do not have the same acces to nice stuff like you guys. But every input is good, maybe i can use it or if not i can allways dream about it.

Thx from HazzarD [ DK ]
 
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The 12HT came with a A440F auto from the factory. To change over you need the whole auto with a torque converter from a diesel and a different bellhousing. Don't know about tranny mount.
However, there is more to it, as you need the idle up from the power steering pump and a/c, a different throttle and a different pedal assembly.
Not that easy, but very doable.
 
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Okay thx for fast response.

But what about that A440F , is it good ? will it hold and are there anything i wanna look for when searching for 1.
 
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Okay thx for fast response.

But what about that A440F , is it good ? will it hold and are there anything i wanna look for when searching for 1.

It is very good, but they tend to need rebuilds around 200k miles. Rebuilding them is not easy and few shops can do it well. With an upgraded valve body torque converter they rock (from Rodney Whole sale in australia).
J
 

Moby

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It is very good, but they tend to need rebuilds around 200k miles. Rebuilding them is not easy and few shops can do it well. With an upgraded valve body torque converter they rock (from Rodney Whole sale in australia).
J

If you need to run an auto it is probably your only choice, but even upgraded it isn't ideal. They are not a performance transmission. They are big and heavy and take some energy to spin. They do not like downshifting out of 4th to 3rd (even with a better VB and TB cable adjustment). They definitely need a VB upgrade, a better torque converter and extra cooling (~$1500 or more if you go with Rodney's upgrades). I had one stock, eventually had it rebuilt with a custom stalled converter, custom VB and eventually a Rodney VB with 3rd gear lock up. FWIW other than the 3rd gear lock up, which will only come in at the same speed as 4th gear lock up (i.e. not at speeds that the A440 will allow in 3rd unless you are in 3rd gear instead of drive), I was not super impressed with the Rodney VB over the one that my rebuilder did for me. When I started having problems with mine after running the Rodney VB for a year the only help he was willing to offer was to bring the transmission to him.

I run an H55f now. I do miss having an auto, but not enough to even remotely consider going back to an A440. On the plus side they should be almost free if you can find one used.
 
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I didn't realize that the Rodney valve body does not go into converter lockup until you reach the same speed as in 4th. 54 MPH is about as fast as you want to go in 3rd, so what is the advantage of that? Interesting.
 

torfab

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I have a few trans on my shop floor, I'll trade you straight across for that 5 speed. ;)

Keep in mind that you will need new drive lines from an auto when you do the conversion.

Lykke til!
 
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Moby - Nice with some hard hitting fact.

Torfab - Yea but since we need to throw it across the litle lake , i'am sure its not worth it in shipping price :( but i'll keep you in mind..

..

And hmm, what about Gm tranny ? was that all a **** idea after all .
C'mon guys i cant be the only old crook here, others must at some point had the same thoughts :p
 

torfab

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If I was still flying through Denmark on my way to Norway I'd bring one with me! But no more SAS flights from Seattle to Copenhagen, we're stuck with Iceland Air to Reykjavik to Oslo.

I don't think anyone makes an adapter for the 2h/12ht to gm auto trans. Only the reverse, gm engine to toyota auto/manual trans
 

Moby

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I didn't realize that the Rodney valve body does not go into converter lockup until you reach the same speed as in 4th. 54 MPH is about as fast as you want to go in 3rd, so what is the advantage of that? Interesting.

It is definitely useful when you're holding the tranny in 3rd climbing a grade. With 4.56 gears and 31.5 (265/75R16) tires I routinely would hold the tranny in 3rd and pull it up to 3000 rpms/60mph climbing the mountain passes around Seattle. Having the 3rd gear lock up in this type of scenario significantly reduces the tranny temps (I ran a oil temp gauge in the return cooler line; I also ran an extra cooler).

But if you don't have these types of scenarios in your usual driving the 3rd gear lock up probably isn't useful. I never noticed it unless I held the tranny in 3rd.
 

Tapage

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nothing to add to your question .. but IMOP 12H-T or even 1HD-T are powerfull enough to be mathed to any auto tranny .. ( less in a heavy 60 or 80 )
 
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Hopefully you don't overlook that one post that mentions a diesel specific a440.

Same tranny as a gasser but has a different valve body which is very important because the diesel spins at a lower rpm than a gas motor so I think you would have all kinds of issues with a gas engine model hooked to a diesel.

So be sure to get a diesel specific model if you try to find a Toyota auto tranny

Tony
 

shibubba

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Hopefully you don't overlook that one post that mentions a diesel specific a440.

Same tranny as a gasser but has a different valve body which is very important because the diesel spins at a lower rpm than a gas motor so I think you would have all kinds of issues with a gas engine model hooked to a diesel.

So be sure to get a diesel specific model if you try to find a Toyota auto tranny

Tony

Very good point.
 
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Kynot62
Ohh yea that was a pretty nice point mate, because that didnt came across in my mind, i had the idea that the converter makes the difference, 1 type for gas and 1 for diesel..

As far as the 12-ht can handle it or not. well i bet ya. its just about the right amount of diesel and boost :)
 

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