Torque converter difference

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plumkrazee70

plumkrazee70

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Napa has two listings for a 42RH lockup converter. One says 904 based and the other says A500 based.
The only reason I question it is the price of them, one is like $15 cheaper.

Can they be interchanged?

Here are the part no:

PMT CR9H (904)
PMT CR67 (A500)
 
Don't know what the difference is but do you have an overdrive?
 
rustycowll69 said:
I may be wrong, but I would assume the OD unit has a lockup converter.
Click to expand...

Not that this is the answer, but there was a 904 lockup AND the 42RH OD with lockup.
I would think one is for each.
904 based could be a lockup for the 904 with only lockup, and the other being a lockup for the A500 with OD.

Boy, that sounds kind of stupid, but I hope you get the idea.
 
TrailBeast said:
Not that this is the answer, but there was a 904 lockup AND the 42RH OD with lockup.
I would think one is for each.
904 based could be a lockup for the 904 with only lockup, and the other being a lockup for the A500 with OD.

Boy, that sounds kind of stupid, but I hope you get the idea.
Click to expand...

I get it and also makes sense. The Carquest one says high stall. I think I'm gonna grab it for my swap.
 
TrailBeast said:
Not that this is the answer, but there was a 904 lockup AND the 42RH OD with lockup.
I would think one is for each.
904 based could be a lockup for the 904 with only lockup, and the other being a lockup for the A500 with OD.

Boy, that sounds kind of stupid, but I hope you get the idea.
Click to expand...

Ok, so here is what the carquest sites says:

A500, A904 Transmission; Lockup; 11" Diameter; 26 Splines; 1.810" Pilot; Slotted Hub; 4 Lug Mount; 10" Bolt Circle; High Stall, "HS Lock Up" Decal; 122 Tooth Ring Gear

Does that description sound right?

Also, the converter is the only part that locks up, regardless of the OD, becuase the OD is in the tail shaft, right? So in my mind it shouldn't matter as long as it fits the A500 and locks up.
 
plumkrazee70 said:
Ok, so here is what the carquest sites says:

A500, A904 Transmission; Lockup; 11" Diameter; 26 Splines; 1.810" Pilot; Slotted Hub; 4 Lug Mount; 10" Bolt Circle; High Stall, "HS Lock Up" Decal; 122 Tooth Ring Gear

Does that description sound right?

Also, the converter is the only part that locks up, regardless of the OD, becuase the OD is in the tail shaft, right? So in my mind it shouldn't matter as long as it fits the A500 and locks up.
Click to expand...

Sounds reasonable to me.:D
 
What about the 4 bolt mounting pad holes spacing in regards to the flex plate? the 904 would have the 4 holes only able to line up in 1 possibility, and the 500, what pattern does it have?
 
Max1196 said:
What about the 4 bolt mounting pad holes spacing in regards to the flex plate? the 904 would have the 4 holes only able to line up in 1 possibility, and the 500, what pattern does it have?
Click to expand...

Should be the same as a 905. It's supposed to bolt up to the LA.
 
I'm referring to the 4 pads on the torque converter, are the 4 holes drilled equally distant from each other or are they irregularly distant from each other like found on a 904 convertor ?
 
Max1196 said:
I'm referring to the 4 pads on the torque converter, are the 4 holes drilled equally distant from each other or are they irregularly distant from each other like found on a 904 convertor ?
Click to expand...

I'm not sure. I don't have an A500 torque converter in front of me, but in all the research I've done, the flexplate remains the same.
 
@TrailBeast I do have a A500, right? I can't find any casting numbers on the case, but I found a number on the tailshaft. It's: 4461036F, which comes up as a 518 tailshaft. In know you can swap 518 and 500 OD units.

The pan does resemble a 904, so I think I'm good, but I need confirmation.

15536512065487328999316143099544.jpg


15536512285271926494243362419282.jpg


IMG_20190326_184715715.jpg


IMG_20190326_184749656.jpg


IMG_20190326_184726946.jpg
 
rustycowll69 said:
looks like a 904 trans pan to me.
Click to expand...

That's what I thought. So it's for sure a A500, which is essentially a 904 with OD. Phew. The0good news is, it appears to have the beefier OD from the 518. Bought this thing a few years ago and now am ready to start planning the swap.
 
Now that I see what vintage your dealing with, my question would not apply, pre 94 stuff, no tone wheel and no cut out in the bell for the p/u sensor.
 
There are 4 different convertors for the 500 / 904 transmissions. Style of hub , lugs or flats for pump gears and odd or even bolt pattern on flex plate bolts, (90 degree is even pattern.
 
plumkrazee70 said:
@TrailBeast I do have a A500, right? I can't find any casting numbers on the case, but I found a number on the tailshaft. It's: 4461036F, which comes up as a 518 tailshaft. In know you can swap 518 and 500 OD units.

The pan does resemble a 904, so I think I'm good, but I need confirmation.

View attachment 1715309726

View attachment 1715309727

View attachment 1715309729

View attachment 1715309730

View attachment 1715309731
Click to expand...
That trans is a A500 or 42 rh trans
 
lkopaska said:
There are 4 different convertors for the 500 / 904 transmissions. Style of hub , lugs or flats for pump gears and odd or even bolt pattern on flex plate bolts, (90 degree is even pattern.
Click to expand...

Well this just got complicated. How do you narrow down the correct one?
 
What motor are you running? Odd or 90 degree flex plate? That unit should use the slotted hub .
The one you have listed in your post from car quest should be correct if it has 90 deree bolt pattern.
Napa cr67 also.
 
lkopaska said:
What motor are you running? Odd or 90 degree flex plate? That unit should use the slotted hub .
The one you have listed in your post from car quest should be correct if it has 90 deree bolt pattern.
Napa cr67 also.
Click to expand...

It's a 340. I'm not sure what bolt pattern those flex plates are. Can you measure?
are.
 
Ok. update for anyone following.

The 340 flexplate will bolt up to the converter of the A500. The converter is neutral balance, so depending on your motor, will determine the plate you need.
 
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