A500 OD spring stuck in Hub??

Davesmopar

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A500 OD spring is completely collapsed inside OD hub, is it possible it is still under tension and stuck or just completely dead and not falling out, the bottom of the spring and OD hub are even.....
 

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Springs do break and I see broken ones all of the time, but honestly, the piston lip seals fail a lot more often - especially if transmission (or that particular clutch) has gotten too hot.
A failed lip seal will either allow fluid to bypass it or will fold over causing the piston to stick or get cocked in its bore.
Also, if the clutches in that clutch pack are wore out, it can allow the piston to overextend allowing the lip seal to bind the piston.

I have seen lip seals so hard, it is like a engine piston ring (they should be soft rubber) or turn into charcoal and shatter when touched (from excessive heat)

A transmission lip seal looks exactly like a large rubber "L", if you were to look at a cross-section of it. The inner part of "L" fits into the piston (grove) and holds it in place. The outer part of "L" uses fluid pressure to push against the bore and that allows for little pressure loss when applied and it springs back when released.

Some transmission rebuilders like to overlook replacing these lip seals during a rebuild (because there are so many of them used) - but replacing them (vs. not) makes the difference between a quality rebuild vs. a so-so job.
BudW
 

Davesmopar

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Never mind, OD spring had collapsed and or welded itself to the OD hub... it's not worth rebuilding....

20220621_182203[1].jpg


20220621_182238[1].jpg
 

BudW

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It has gotten incredibly hot! You can tell by the metal discoloration on the top picture.
A rhetorical question, but how hot do you need to discolor metal?

With that amount of metal (iron/steel and aluminum) floating about, it will take a lot of time to make sure all of it is all cleaned out, which is a time intensive job.
Finding a replacement, might be a better plan.
 

Davesmopar

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Yeah, the direct drum, low/reverse drum, clutches and most of the OD unit are cooked...
Plan B, looking for a rebuildable core or a good used one...
 

BudW

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Depending on what year transmission you find - you might have to reuse your existing case (if good) and/or valve body.
You valve body shouldn't be damaged per-se, but it will need a thorough/in-depth cleaning.
BudW
 

Davesmopar

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I probably replace more than I need to when building a transmission, and ALL VB's come apart 100% for cleaning...

It's a 1988 Dakota V6 RWD, not sure if that would be a 40RH or 42RH, being a basic V6 RWD I would guess a 40, but that is about all I am confused about.....

The main concern was with the (800 pound) Spring being stuck in the OD hub, so I just put the high tension snap ring back on it and set it aside after looking under the hub at the damage and figured I can't reuse it anyway....
 

Davesmopar

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Depending on what year transmission you find - you might have to reuse your existing case (if good) and/or valve body.
You valve body shouldn't be damaged per-se, but it will need a thorough/in-depth cleaning.
BudW
BudW, by any chance do you know what years/vehicles are directly interchangeable, meaning plug and play???
Its a 1988 Dakota V6 RWD A500 Main part of VIN if needed 1B7GN14X1JS****** I have the complete VIN if needed....
 

Aspen500

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Should be 1987 to early 1996 Dakota interchange. At some point in the 96 model year it went to full electronic. My early (Aug 15, 1995) build 96 Dakota has only OD and TCC electronic.
 

Davesmopar

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Should be 1987 to early 1996 Dakota interchange. At some point in the 96 model year it went to full electronic. My early (Aug 15, 1995) build 96 Dakota has only OD and TCC electronic.
OK, so as long as RWD V6 Dakota RH and not RE it should bolt in and plug in....
 

Aspen500

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If you have a good (meaning nice people) salvage yard near you, they would be able to look up and tell you which years and models of trucks are a direct interchange. Probably online now, but they used to have those big Hollanders Interchange books behind the counter.
 

Davesmopar

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If you have a good (meaning nice people) salvage yard near you, they would be able to look up and tell you which years and models of trucks are a direct interchange. Probably online now, but they used to have those big Hollanders Interchange books behind the counter.
Thank you, that led me to Pullapart Interchange, mainly for newer vehicles, but you could use it to retro fit the OD's for the FMJ's out there....


Sorry, didn't mean for this to turn into a Dakota thread, but hopefully it will help someone working on an OD unit for their Hot Rods, giving a little more insight to the A500, RH/RE series Transmissions....
 

Davesmopar

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Looks like I was wrong on the years that are plug and play, oops.

If I read it right, 87-91 3.9 Dakota and 3.9 D100/D150 are direct interchange, correct?
Yes, that is what I am seeing looking at car-part.com also for transmissions...
However I am pretty sure that is with the torque converter...

I have a sneaky feeling that taken the converter out of the equation, then it will be much more interchangeable, as the flywheel and balance changed in 92 making the converter change as well.... I also think that the 5.2/5.9's would work with the correct 3.9 converter.....

And if I understand it correctly, the 1st number is the gear count (30RH 3 speed, 40RH 4 speed), the 2nd number is how strong it is (40,42,46,48... and stronger = bigger engine size)(bigger the number the stronger it is) and of course the RH/RE, H = Hydraulic Governor and E = Electronic Governor.... (most probably already new that last part lol) And the R stands for RWD.....
 
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