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Would 3.73s be a solid upgrade

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Old Dec 16, 2025 | 09:45 AM
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Default Would 3.73s be a solid upgrade

I have a 2002 35th Anniversary Edition SS Camaro
Just installed bbk shorty headers,slp airlid with k&n air filter,ssra ftra,slp loudmouth exhaust catback,and i have purchased a diablosport intune i3 platinum for tuning.Would 3.73s compliment this build?
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Old Dec 16, 2025 | 01:36 PM
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You didn't mention transmission type, but I wouldn't recommend that gear swap no matter which transmission you have.

If you have a manual, then you already have 3.42 gears. In this case, you'll definitely want to step up to a 4.10 gear as the 3.73 swap is just not worth it when 4.10 will give you much better gains and make 6th gear much more usable at highway cruise. There's really no downside with going straight to 4.10s.

If you have an auto, then you already have 3.23 gears (standard on an auto SS car). The swap to 3.73 would be very expensive (unless you can do the labor yourself) while showing only a very modest improvement. You also may introduce new problems (such as gear whine, etc.) if the install is not perfect and/or depending on the brand of gears. If you have the auto, I would highly recommend upgrading the torque converter instead. A top shelf unit in the 3200-3600 rpm range would be an excellent choice for a bolt-on street machine/daily driver. You want to go with a good brand here, like Yank or FTI or Circle D, etc., as that will make all the difference in how the converter behaves. Get a good brand and the gains will be exponentially better than a gear swap while still driving very close to stock at part throttle. And with an LS1 + 4L60E setup, once you have a converter stall speed of 3500+, the gains from a 3.23 to 3.73 swap are limited to no more than 1 tenth of ET reduction (so very little is left on the table). With the converter swap, your highway MPG won't be impacted (unlike with the gear swap) because rpms will remain the same as stock once you're at converter lock-up speeds.
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Old Dec 16, 2025 | 05:27 PM
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Originally Posted by RPM WS6
You didn't mention transmission type, but I wouldn't recommend that gear swap no matter which transmission you have.

If you have a manual, then you already have 3.42 gears. In this case, you'll definitely want to step up to a 4.10 gear as the 3.73 swap is just not worth it when 4.10 will give you much better gains and make 6th gear much more usable at highway cruise. There's really no downside with going straight to 4.10s.

If you have an auto, then you already have 3.23 gears (standard on an auto SS car). The swap to 3.73 would be very expensive (unless you can do the labor yourself) while showing only a very modest improvement. You also may introduce new problems (such as gear whine, etc.) if the install is not perfect and/or depending on the brand of gears. If you have the auto, I would highly recommend upgrading the torque converter instead. A top shelf unit in the 3200-3600 rpm range would be an excellent choice for a bolt-on street machine/daily driver. You want to go with a good brand here, like Yank or FTI or Circle D, etc., as that will make all the difference in how the converter behaves. Get a good brand and the gains will be exponentially better than a gear swap while still driving very close to stock at part throttle. And with an LS1 + 4L60E setup, once you have a converter stall speed of 3500+, the gains from a 3.23 to 3.73 swap are limited to no more than 1 tenth of ET reduction (so very little is left on the table). With the converter swap, your highway MPG won't be impacted (unlike with the gear swap) because rpms will remain the same as stock once you're at converter lock-up speeds.
It has the factory 4l60E this car has pretty low mileage 54k
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Old Jan 3, 2026 | 06:05 AM
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Do the converter then. The gears are pointless in an auto, like RPM said.
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Old Jan 4, 2026 | 10:44 PM
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Converter, cooler, drag radials and a tune will give you a dramatic and very noticeable gain in performance.
And don't be nervous about a 3400-3600 stall for daily driving.
I have had my yank SS3600 stall for years now and daily drive my car anytime the weather is half way decent
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Old Jan 5, 2026 | 12:02 AM
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+3 on swapping in a looser converter. Something around a 3200 is very drivable. Much better ROI than a gear in an auto.
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Old Jan 5, 2026 | 08:43 AM
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I like my 3.73 with a M6. 5th gear is more usable on back roads. 3.90 if they are available for your rear end.
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