NSG370 6-Speed to NV3550 5-Speed Conversion Help

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Kestes

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Denver CO
My NSG370 is on it's last leg. Too expensive to fix and special tools etc.. Has anyone replaced it with the NV3550? The length seems to be 4/10 inch difference, and i'd need a bell housing for the 3550.
2005 Rubicon, 4.0 engine , NV241 OR rock transer case. If anyone knows if the transfer case will bolt up fine or not, or have any other experience with this, please let me know. Thank you
 
Kestes said:
My NSG370 is on it's last leg. Too expensive to fix and special tools etc.. Has anyone replaced it with the NV3550? The length seems to be 4/10 inch difference, and i'd need a bell housing for the 3550.
2005 Rubicon, 4.0 engine , NV241 OR rock transer case. If anyone knows if the transfer case will bolt up fine or not, or have any other experience with this, please let me know. Thank you
Click to expand...

You'll need a conversion bellhousing. It has both holes for the CPS, the original location on the left side for the NV and then the one on the right side over the starter for the NSG. The flywheel stays the same along with the rest of the clutch bits. We used the conversion kit from AA with zero issues but we were doing an auto swap in the 05, so there may be some oddity I missed.
 
Kestes said:
My NSG370 is on it's last leg. Too expensive to fix and special tools etc.. Has anyone replaced it with the NV3550? The length seems to be 4/10 inch difference, and i'd need a bell housing for the 3550.
2005 Rubicon, 4.0 engine , NV241 OR rock transer case. If anyone knows if the transfer case will bolt up fine or not, or have any other experience with this, please let me know. Thank you
Click to expand...

I replaced mine with an AX15, but the process is the same.

T case will bolt up. I used Advance Adapters bellhousing but others have used the Novak just fine as well.

The only thing that isn't purely bolt on is you'll have to replace the connector on your reverse switch and some light fabrication to adapt a shift boot because the shifter may not be in exactly the same spot.
 
Kestes said:
My NSG370 is on it's last leg. Too expensive to fix and special tools etc.. Has anyone replaced it with the NV3550? The length seems to be 4/10 inch difference, and i'd need a bell housing for the 3550.
2005 Rubicon, 4.0 engine , NV241 OR rock transer case. If anyone knows if the transfer case will bolt up fine or not, or have any other experience with this, please let me know. Thank you
Click to expand...

Is the nv3550 something you have already? If not I would look for an ax15 instead
 
mrblaine said:
You'll need a conversion bellhousing. It has both holes for the CPS, the original location on the left side for the NV and then the one on the right side over the starter for the NSG. The flywheel stays the same along with the rest of the clutch bits. We used the conversion kit from AA with zero issues but we were doing an auto swap in the 05, so there may be some oddity I missed.
Click to expand...

Many thanks!
 
Kestes said:
My NSG370 is on it's last leg. Too expensive to fix and special tools etc.. Has anyone replaced it with the NV3550? The length seems to be 4/10 inch difference, and i'd need a bell housing for the 3550.
2005 Rubicon, 4.0 engine , NV241 OR rock transer case. If anyone knows if the transfer case will bolt up fine or not, or have any other experience with this, please let me know. Thank you
Click to expand...

Thanks all! Huge help
 
Kestes said:
No, I do not have it yet. I would imagine the newer 241 trans case would need an adapter if going to the AX 15?
Click to expand...

No, the same t case fits all 3 manual transmissions. I've had the same case from an AX15 on an nsg370 and now it's back on an AX15 again.

AX15 vs nv3550 is a tradeoff. Nv3550 has a better (lower) first gear but you can still get brand new AX15s. I've never personally driven a 3550 but I've heard people not like the shift feel. Probably more of a personal preference thing. It matters exactly zero when it comes to doing the swap.
 
freedom_in_4low said:
No, the same t case fits all 3 manual transmissions. I've had the same case from an AX15 on an nsg370 and now it's back on an AX15 again.

AX15 vs nv3550 is a tradeoff. Nv3550 has a better (lower) first gear but you can still get brand new AX15s. I've never personally driven a 3550 but I've heard people not like the shift feel. Probably more of a personal preference thing. It matters exactly zero when it comes to doing the swap.
Click to expand...

Copy that. Thanks
 
freedom_in_4low said:
No, the same t case fits all 3 manual transmissions. I've had the same case from an AX15 on an nsg370 and now it's back on an AX15 again.

AX15 vs nv3550 is a tradeoff. Nv3550 has a better (lower) first gear but you can still get brand new AX15s. I've never personally driven a 3550 but I've heard people not like the shift feel. Probably more of a personal preference thing. It matters exactly zero when it comes to doing the swap.
Click to expand...

It gets pretty silly. I've swapped them both ways for folks. AX to NV and then NV to AX. They had their little list of reasons why one is more favorable, I never understood them.
 
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mrblaine said:
It gets pretty silly. I've swapped them both ways for folks. AX to NV and then NV to AX. They had their little list of reasons why one is more favorable, I never understood them.
Click to expand...

My reasoning to go ax15 is simple..availability. I can still get a brand new one on my door step in a week. The same can't ve said for a nv3550. I in no way dislike the 3550 I just like efficiency
 
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P man said:
My reasoning to go ax15 is simple..availability. I can still get a brand new one on my door step in a week. The same can't ve said for a nv3550. I in no way dislike the 3550 I just like efficiency
Click to expand...

Mine was the same plus familiarity, because I'd had the AX15 in my 99. If I'd never driven either I might have gone with a reman NV, but I can't picture myself swapping either one for the other.
 
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