Transmission Output Shaft Question

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RichardR

RichardR

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Hi all,
I have a A999 lock up transmission I just picked up and I did a search to find out what i that would need to change and be aware about when changing from my original 904 in my 72 Scamp . There's not a whole lot different but i know i would need a 1968+ crank for the converter. I think i read something about the output splines for the driveshaft slip yoke are different. Are the 904 and 999 output shafts differently splined and if so where can i find the proper slip yoke?
Are the slip yokes the same length so i can reuse the driveshaft?
Thanks
 
RichardR said:
Hi all,
I have a A999 lock up transmission I just picked up and I did a search to find out what i that would need to change and be aware about when changing from my original 904 in my 72 Scamp . There's not a whole lot different but i know i would need a 1968+ crank for the converter. I think i read something about the output splines for the driveshaft slip yoke are different. Are the 904 and 999 output shafts differently splined and if so where can i find the proper slip yoke?
Are the slip yokes the same length so i can reuse the driveshaft?
Thanks
Click to expand...

The converter is different between the two of course, but the output hardware should be the same (maybe a different U joint but the yoke should be compatible)
 
TrailBeast said:
The converter is different between the two of course, but the output hardware should be the same (maybe a different U joint but the yoke should be compatible)
Click to expand...

So you think if i pull the tranny, leave the driveshaft, and drop the new tranny in the slip yoke will slide into the rear of the transmission with no issue?
What do you mean by the U joint may need to be changed?
 
RichardR said:
So you think if i pull the tranny, leave the driveshaft, and drop the new tranny in the slip yoke will slide into the rear of the transmission with no issue?
What do you mean by the U joint may need to be changed?
Click to expand...

Sorry, I thought you were swapping yokes so disregard the U joint statement.
Yes, the driveshaft should fit fine.
 
RichardR said:
Hi all,
I have a A999 lock up transmission I just picked up and I did a search to find out what i that would need to change and be aware about when changing from my original 904 in my 72 Scamp . There's not a whole lot different but i know i would need a 1968+ crank for the converter. I think i read something about the output splines for the driveshaft slip yoke are different. Are the 904 and 999 output shafts differently splined and if so where can i find the proper slip yoke?
Are the slip yokes the same length so i can reuse the driveshaft?
Thanks
Click to expand...
Unless I'm misreading your post, why would you need to change the crank for the converter. All A999 and 904 converters have the same size crank pilot from 1968 on. The pilot (or snout as some call it) measures 1.810". Only the pre-68 cranks have the smaller, 1.550" pilot.
 
transman said:
Unless I'm misreading your post, why would you need to change the crank for the converter. All A999 and 904 converters have the same size crank pilot from 1968 on. The pilot (or snout as some call it) measures 1.810". Only the pre-68 cranks have the smaller, 1.550" pilot.
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No i was just saying i know this one fact
 
transman said:
Unless I'm misreading your post, why would you need to change the crank for the converter. All A999 and 904 converters have the same size crank pilot from 1968 on. The pilot (or snout as some call it) measures 1.810". Only the pre-68 cranks have the smaller, 1.550" pilot.
Click to expand...

Are the tail housings the same between the slant trans and v8 trans?
 
I think 65, 66, and 71 or was it 68 on the rear seal? I never go by the year cuz they have all been apart before and parts changed.
 
CudaFactHackJob said:
I think 65, 66, and 71 or was it 68 on the rear seal? I never go by the year cuz they have all been apart before and parts changed.
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So say, for example, i want to change the tail on my 85 A999 for small block with one from my 71 A904 slant 6, i wood need to change the seal based on the year of tailshaft used?
 
Well the tailshaft is the splined part that turns. The tail housing is the casting that holds the seal. The seals should be the same. Not too sure about the double ears for the shift linkage tho. But why change anything? The driveshaft from the 72 will fit the later trans.
 
CudaFactHackJob said:
Well the tailshaft is the splined part that turns. The tail housing is the casting that holds the seal. The seals should be the same. Not too sure about the double ears for the shift linkage tho. But why change anything? The driveshaft from the 72 will fit the later trans.
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Well it's more of the case in case i ever break the housing, i have a spare
 
RichardR said:
Are the tail housings the same between the slant trans and v8 trans?
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The extension housing bushing the same from 1968-2003.
The extension housing seal: 1966-72:- 2.254", non booted type
1972-2003:-2.375". and are available either with or without the boot.
 
RichardR said:
Why is there both the boot and non boot for the later ones.
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It might have been a factory thing. When I owned the '74 Challenger, the transmission had never been out(I was the 2nd owner) and from sitting for over 20 years it leaked from every orifice, so a reseal was necessary. The extension seal was the booted type. We carried both in stock because, some rebuilders wanted the non boot style, others would only use the booted style.
Picture of the Challenger. Bought in 2002 off the original owner. 32000 or so miles at time of purchase. Rallye package, 360/727/3:55 sure grip. Other than doing a major tune up, new tires, new battery and the transmission reseal and of course washing and waxing it, it didn't need much. Never driven (according to the seller) but was run on a regular basis in the driveway. It was parked in his garage in 1979.

My Challenger.png
 
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transman said:
It might have been a factory thing. When I owned the '74 Challenger, the transmission had never been out(I was the 2nd owner) and from sitting for over 20 years it leaked from every orifice, so a reseal was necessary. The extension seal was the booted type. We carried both in stock because, some rebuilders wanted the non boot style, others would only use the booted style.
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Is there benefits to use one over another?
 
I like the booted one; so the customer doesn't accuse me of switching his tranny with a shorter one when he puts it back in and sees an inch of shiny yoke showing!
 
CudaFactHackJob said:
I like the booted one; so the customer doesn't accuse me of switching his tranny with a shorter one when he puts it back in and sees an inch of shiny yoke showing!
Click to expand...
That’s right. The boot is called a dust boot to keep dust and other foreign crap from getting to the lip seal and destroying it. Kim
 
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