Ox Locker in GMT900 with 3.42 gears?

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swathdiver

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Most 4-speed trucks set up for max towing come with 3.73s. If yours was a lighter duty optioned model, it would have 3.42s and or 3.23s depending on the engine. A 4.10 upgrade is quite common.

Below are three examples of the gear multiplication and RPMs at speed for a given gear with new stock sized tires:

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See the torque multiplication with each gear change for each gear in the transmission? How many rpms do you want to be turning on the highway?

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When talking gear swaps, it's important to establish what kind of transmission we're dealing with. A 4.10 gear set is not necessarily the best thing for a 3-speed or 10-speed transmission for example. Lower numeric ratios would deliver better overall performance. Another way to look at it is that 4.10s behind a 4-speed don't come close to equaling the performance of 3.42s behind a 6-speed.
 
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07CLASSIC

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Most 4-speed trucks set up for max towing come with 3.73s. If yours was a lighter duty optioned model, it would have 3.42s and or 3.23s depending on the engine. A 4.10 upgrade is quite common.

Below are three examples of the gear multiplication and RPMs at speed for a given gear with new stock sized tires:

View attachment 451333

View attachment 451334

View attachment 451335

See the torque multiplication with each gear change for each gear in the transmission? How many rpms do you want to be turning on the highway?

This comment is directed to everyone:

When talking gear swaps, it's important to establish what kind of transmission we're dealing with. A 4.10 gear set is not necessarily the best thing for a 3-speed or 10-speed transmission for example. Lower numeric ratios would deliver better overall performance. Another way to look at it is that 4.10s behind a 4-speed don't come close to equaling the performance of 3.42s behind a 6-speed.
Very useful. Thanks, SD.
 
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07CLASSIC

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4.30 gears!
You're doing that on purpose, right? :)

Now I've gotta look into another possible option. And, to be honest, I don't do much highway at all these days so I could logically make a case for 4.10/4.30.

There's a possibility I could be towing on highways more in future though, but .... what if I'm not?

Thanks for that.
 
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07CLASSIC

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I am gotta get a quote and make a appointment for a alignment
Hey you didn't regear when you got your TrueTrac, did you? If so, gimme the price of the parts and labor when you get your invoice. Just for a reference. I know everybody charges differently.
 

Doubeleive

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Hey you didn't regear when you got your TrueTrac, did you? If so, gimme the price of the parts and labor when you get your invoice. Just for a reference. I know everybody charges differently.
no but i believe it required (or I requested) a new pinion set regardless, I purchased a new yoke separate from the dealer
mine is 3.42 already. the one I need to change now is in the Silverado, finding a gu6 front diff should be no problem, the issue it is has the 9.5" rear end, not even sure if they make a truetrac in the 9.5. in any case need to pay down some debt first before I open that can of worms. could not find a 3.42 silverado when I was shopping for it with the options I wanted anyway. one Sierra denali showed up on a lot with everything I wanted, called the dealer late in the day and they didn't even have it priced yet, called the next morning and they said they sent it to auction :mad: :mad: :mad: :mad:
 
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