Tranny Rebuild -Shadetree Mechanic Style (1 Viewer)

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Update 1-1-06

Well, if you thought I was crazy for rebuilding a tranny then you'll get a kick out of this.

I went wheelin on New Year's Day with Ali and some Landrover Discovery's for some more testing. Everything was running fine however I was cauious as the terrain with wet and soupy.

The tranny pulled strong on a 30º incline on a semi-dry hard packed dirty trail.


Enjoy
1-1-06 badlands.jpg
 
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Jimmy, with all the money you saved rebuilding the tranny yourself, now you can get some sliders. Looks like not a moment too soon. :)
 
This is perhaps the most well done project thread I've seen in the site.

I spent a year in a job where I rebuilt auto transmissions all day every day for ten to twelve hours a day and can add a very few comments.

Auto transmissions are pretty much all alike internally. Some are clutchpack only, some combine bands and clutches to make their various shifts, but they are all fairly simple inside, except for their valve bodies. There should be no reason for anyone who could dissassemble, measure, and reassemble an engine to have any fear of approaching that job in an automatic transmission.

The industry maintains an aura of mystery and complication about these mechanisms that is simply not true. They do it in order to keep you coming in for the ridiculously high pricing.

Torque converters are indeed rebuilt. They aren't done in shop, but there are plenty of nationwide rebuilding operations that cut the weld, fix the vanes and oneway clutch, seal them and reweld them on assembly lines. A "rebuilt" torque converter can be as good as a new one.

You can pretest each clutchpack with compressed air and a rubber nozzle. After you've installed the clutches and seals and have the clearance as specified put air to the holes between rings until you hear the clutch 'thunk' in and out. During road test a pressure gauge can tell you if everything is happening with correct timing and if the pump is generating enough pressure. There's almost always a way to externally adjust the trans line pressure and that should be in the individual manuals. Some manuals don't include the info assuming a correct rebuild will result in correct pressure. (I guess, but don't know, that the specs for pressure are not often included anymore so if I were doing one today I'd try to ask someone who's raced the trans. Racers ALWAYS mess with those pressures to get firm fast engagements).

The reason for not opening the valve body is that the pistons may sieze in their bores afterwards. A used valve body has expanded and shrank as it heats and cools in use and that can cause those little pistons to wear-in unevenly. Many if not most rebuilders take the safe course of not disturbing the set of the mechanism if it was working fine. Unless the halves are perfectly torqued a slight twist can be added causing clearances to close up. There are very fine tolerances in those piston to bore fits and any change there can cause abberant transmission behaviors. Also, the valve body usually isn't the cause of a trans failure. Seldom is, actually, except in Ford C4 and C6 transmissions which used rubber check balls instead of steel ones found in all others. I think the rubber was a designed failure as those balls would melt into little piles of black goo. The trans wouldn't work even though often the clutches and band weren't badly worn. Anyway, it would have been safe to flush the valve body in a container of clean fluid, moving the shift lever and any other piece you could. The new fluid and operating pressure would take care of that clutch material at your first service.. It'd all be down in the pan.

Automatic transmissions are all about good parts and correct measurements/clearances as you've found out so well.

That thing you called a "prawn", Jim, is usually known as a "pawl", as in "parking pawl" for the park position locking. I got a kick out of your usage but then began to wonder if maybe the Japanese might actually call it a prawn! (Nope, if the manual spells it like that it's a bad translation or a typo).

Congrats on a successful job of it!! I know the feelings you had while trying it out, and the eggshell you had under your right foot until you came to believe that it really would work.
 
Let's all remember that this project did not end as well as we might have hoped: https://forum.ih8mud.com/showthread.php?t=122074

Regardless, this is still a kick ass technical documentation of a very difficult procedure. I know that sure as s*** I wouldn't attempt this one bit with my A343.

I would probably get a used tranny, R & R the old one, and then with a running truck, go ahead and have fun rebuilding a tranny.

Jimmy's a hero for this thread in my book and probably understands cruiser auto's pretty well know because of this experience, regardless of the eventual negative outcome.

-o-
 
this is still a kick ass technical documentation of a very difficult procedure...

...Jimmy's a hero for this thread in my book and probably understands cruiser auto's pretty well now because of this experience

Absolutely.

I agree 100%.

Curtis
 
Let's all remember that this project did not end as well as we might have hoped: https://forum.ih8mud.com/showthread.php?t=122074

Curtis,

Yes, the project did end in failure. [How's the old proverb go: better to fail trying than to never try.] But I have learned many things along the way and I'm still learning. Acutally, I am still investigating the problem with a local tranny guy that has rebuilt the A440F. After talking with him I may have to change my theory on the failure mode.

I'll keep you informed and thanks for being so understanding.

(I should probably tie the two threads together.)



Shadetree Mechanic Tranny Rebuild (Part 2)
https://forum.ih8mud.com/showthread.php?t=122074
All, please read this thread for additional results.
 
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jklubens, sory to see this.

I don't see a torque converter listed in your accounting of costs in this thread. Did you use a new one, or what?
 
Yes, the project did end in failure.
It was a success for a while though ;)

I've had the valve body on and off mine a few times now trying to solve problems and this thread has convinced me I should have a go at rebuilding the tranny myself next time it's needed (rebuilt 10K miles ago by a 'profesional' and is already failing again).
 
I had a GM tranny rebuilt by a local builder, I think he just took things apart and reassembled and charged me $$$. Now a good builder would charge more $$$$ but in the end you hope you get what you asked/paid for. The downfall to slushboxes...
 
Ditto

Curtis,

Yes, the project did end in failure. [How's the old proverb go: better to fail trying than to never try.] But I have learned many things along the way and I'm still learning. Acutally, I am still investigating the problem with a local tranny guy that has rebuilt the A440F. After talking with him I may have to change my theory on the failure mode.

I'll keep you informed and thanks for being so understanding.

(I should probably tie the two threads together.)



Shadetree Mechanic Tranny Rebuild (Part 2)
https://forum.ih8mud.com/showthread.php?t=122074
All, please read this thread for additional results.

Great project and details. I did not rebuiled mine, but
the end result was the same.


I have an FJ-62; had my A440F replaced witha low mileage bring back from Japan and with a rebuilt Torque Convertor;
lasted only about 15K miles;
that guy in Australia ?ORTO, writes on his website a lot about
these trannies and the problems with heat, poor valve body design,
poor TC design, need for an auxilary cooler, etc.etc

He apparently has solved these design problems in his rebuilt/redesigned A440F tranny.

Unfortunately, I read this after my tranny failed, for the second time.



G
 
A440F Rebuild

Hi Cruiser Jimmy,

I'm writing from Pakistan. I have an '89 HJ61 with the same auto trans problems as yours. Who is Rodney in OZ? And can I order parts for a tranny rebuild from Rodney? Any help would be appreciated. Thanks and regards, Mujahid.
 
This is Rodney's shop in Australia (OZ):

Wholesale Automatic Transmissions

They had a fire there a while ago which really set them back, so you may have a hard time getting through. I don't know if their operations are back to normal yet or not.

Regardless, buying from Rodney is a great way to go.

Welcome to the forum,

Curtis
 
Very nice find!
 
Very nice find!

There is another sst kit on eBay right now. Looks complete.


Edit: I was wrong there are two sets on eBay. Don't see that every day.
 
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