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I think it's been asked before but I can't find a clear, exact answer. Is the only thing I need to swap a manual lsd into an open diff e shift the differential itself? What about if I manage to find an auto lsd?
 

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All you NEED is the ring gear if you are trying to change your gear ratio.

But whenever you change the ring gear, you need to get your backlash checked and set.

The carrier is also refered to as the pumpkin.

This is a complete one.


I just removed my manual lsd in favor of an auto diff. I'm interested to see how it performs.
 

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thanks a lot. let me know if the auto diff gearing makes a huge difference. I haven't been able to find those for sale since they're rare so i don't want to make my gear ratio noticeably longer.
 

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Took the car for a test drive, and the final drive change was noticeable. I'm definitely happy with the change. I haven't driven it on the freeway other than for a mile, and I forgot to pay attention to cruising speeds. But it certainly didn't catch my attention. I'll post up more later on once I get the chance.
 

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Took the car for a test drive, and the final drive change was noticeable. I'm definitely happy with the change. I haven't driven it on the freeway other than for a mile, and I forgot to pay attention to cruising speeds. But it certainly didn't catch my attention. I'll post up more later on once I get the chance.
Nice, so your car is a 5MT that came with the M85 (Manual)
LSD and you swapped it for an M98 (Auto) LSD?

Please share your further findings
 

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I also switched to the auto 3.91 ratio last year when I installed my TRD LSD. It's a noticeable if you know your car/gearing well, but its not like day and night huge difference.
 

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Nice, so your car is a 5MT that came with the M85 (Manual)
LSD and you swapped it for an M98 (Auto) LSD?

Please share your further findings
Yes, came with the m85 lsd, and I swapped it for the ring and pinion off of an M96 (open auto).

Finally got a chance to drive the car for more than a couple minutes after an alignment.

Acceleration is peppier, and at 65mph, cruising rpm is 3k.

So by no means is the car louder or feeling as if it is geared like a jack rabbit while on the freeway. Plus passing power is a little bit better thanks to the higher gearing and sitting closer to the powerband.
 
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