NSG370 vs 42RLE

astjp2 said:
Yes for the YJ, the cj was either/or, the 727 was lockup in early 80’s and the old ones used the kickdown and rpm for lockup. Not solenoids. Yj has solenoids I believe. It’s been a lot of years for details to remember. https://www.novak-adapt.com/knowledge/transmissions/automatic/727
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Interesting. Started in '78 on the 727.years before ford and gm. I'd never heard of a mechanical lockup based off output shaft speed.

Depending on how well that system works it sounds like a bolt in swap for stroker 6 guys(258 crank pocket) that want to go auto but not source the pcm and other electronic bits for a 32rh.
 
Speaking of 258 cranks,i believe its pilot hole is the same as the amc v8?

Since the 6 and v8s had the same bell pattern you could even use an amc spec th400 behind a stroker if you really wanted something that could take a beating. Not that the 727 can't be built,it's just another option
 
Rickyd said:
It looks like the 999 also had a mechanical lockup option. Learned something new today
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I had heard of that but never could find much about it. Reading about all the different iterations of autos over the 70/80/90s, I get very confused quickly. 999, 904, 32RH, lockup, non lockup, etc.

All I know is that the 87-93 YJs were referred to as non lockup and the 94-95 had an electronic locking TC
 
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Rickyd said:
Speaking of 258 cranks,i believe its pilot hole is the same as the amc v8?

Since the 6 and v8s had the same bell pattern you could even use an amc spec th400 behind a stroker if you really wanted something that could take a beating. Not that the 727 can't be built,it's just another option
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Turbo 400 is not even in the same league, there is a reason the 727 had adapters to fit behind chevies and fords.
 
machoheadgames said:
I had heard of that but never could find much about it. Reading about all the different iterations of autos over the 70/80/90s, I get very confused quickly. 999, 904, 32RH, lockup, non lockup, etc.

All I know is that the 87-93 YJs were referred to as non lockup and the 94-95 had an electronic locking TC
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The early yj was mechanical lockup, my 94 has an extra plug for the lockup solenoid.
 
The worst thing about the 727 is the reverse drum rotating at 2.2 time crank speed backwards. It actually can fail catastrophicly.
 
astjp2 said:
The early yj was mechanical lockup, my 94 has an extra plug for the lockup solenoid.
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I believe you, just couldn’t find any info on it myself when I looked. I read a bit through the FSM diagrams and descriptions of the transmission (older FSMs) but I didn’t see much, or at least not much that I understood to be related to a mechanical lockup.
 
I enjoy driving my manual. I did, at one point recently, search for an auto for the wife. But we canned those plans. I think I drove only one auto TJ and it was probably about close to 18 years ago. No idea what the experience is like.
 
machoheadgames said:
I believe you, just couldn’t find any info on it myself when I looked. I read a bit through the FSM diagrams and descriptions of the transmission (older FSMs) but I didn’t see much, or at least not much that I understood to be related to a mechanical lockup.
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If the torque converter is removed, the input shaft is different for the lockup. The factory manual for the transmission also has a color diagram of the circuits.
 
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Rickyd said:
It looks like the 999 also had a mechanical lockup option. Learned something new today
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I always thought the primary difference between the 904 & 999 (beside the bellhousing/bolt pattern) was the strength of the 2 planetary assemblies. I believe the 904 used a 3 pinion planetary, whereas the 999 used a 4 pinion planet. And then I believe the 999 has 1 or 2 additional frictions in one or both of the clutch packs. I bet the FSM shows this, although I've never looked.
 
hear said:
I always thought the primary difference between the 904 & 999 (beside the bellhousing/bolt pattern) was the strength of the 2 planetary assemblies. I believe the 904 used a 3 pinion planetary, whereas the 999 used a 4 pinion planet. And then I believe the 999 has 1 or 2 additional frictions in one or both of the clutch packs. I bet the FSM shows this, although I've never looked.
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Were there different versions of 904s with the bellhousings they had? I was always under the impression the 904 was for 4 cylinders...which were a different bellhousing. But I really don't follow or know much about any of the different auto options.
 
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hear said:
I always thought the primary difference between the 904 & 999 (beside the bellhousing/bolt pattern) was the strength of the 2 planetary assemblies. I believe the 904 used a 3 pinion planetary, whereas the 999 used a 4 pinion planet. And then I believe the 999 has 1 or 2 additional frictions in one or both of the clutch packs. I bet the FSM shows this, although I've never looked.
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machoheadgames said:
Were there different versions of 904s with the bellhousings they had? I was always under the impression the 904 was for 4 cylinders...which were a different bellhousing. But I really don't follow or know much about any of the different auto options.
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I assumed the 30rh was based on the 904 and the 32rh was based on the 999. Could be wrong though
 
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machoheadgames said:
Were there different versions of 904s with the bellhousings they had? I was always under the impression the 904 was for 4 cylinders...which were a different bellhousing. But I really don't follow or know much about any of the different auto options.
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They were ran behind small block mopar and some amc v8’s
 
Rickyd said:
I assumed the 30rh was based on the 904 and the 32rh was based on the 999. Could be wrong though
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That has been my assumption as well. I have (what I'm told is) a 30RH core in my garage along with a 32RH core right next to it. Need to rebuild the 32RH, but I want to open the other at the same time to really deep dive on the differences. Externally, these appear to only vary on the bellhousing. The 30RH has a more triangular bellhousing. ¯\_(ツ)_/¯
 
hear said:
That has been my assumption as well. I have (what I'm told is) a 30RH core in my garage along with a 32RH core right next to it. Need to rebuild the 32RH, but I want to open the other at the same time to really deep dive on the differences. Externally, these appear to only vary on the bellhousing. The 30RH has a more triangular bellhousing. ¯\_(ツ)_/¯
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Chevy 60* v6 pattern if I'm not mistaken.

A lot of motors use that pattern. turbo buick,northstar,fwd LS,and others. You could do some really odd engine swaps.
 
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They are all based on the 904, the difference is in the bell housing and other minor changes but the parent design is still the same transmission
 
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