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Discussion Starter · #1 ·
I have a 2010 RT with automatic 5 speed. Looking to go with a getrag 3:73 differential.
Does anyone have this? Pro’s & Con’s?
Really wanting to know how many rpm’s it’ll be turning at 70mph etc
 

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The Bacon Hauler (‘12 Cop Charger)
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From a couple threads I’ve seen on this topic, I gathered that the 3.73 was a little much for cars that take highway trips, as MPGs take big hit.

Here’s a breakdown of RPMs by MPH and gear for you to decide for yourself:

998037
 
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The Bacon Hauler (‘12 Cop Charger)
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So at 70mph with a 2010 RT 5.7 I should be turning 2,540rpms correct?
If you are running the 245/45/20s and have the NAG1 5 speed auto trans
 

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The Bacon Hauler (‘12 Cop Charger)
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Also is there any way I could get that calculator spreadsheet? I’d like to compare the 3:06, 3:73 & 3:91
yeah, its one I created myself to judge different RPMs back when I had my first Challenger and wanted to upgrade rear-ends, so it’s saved in my Google Drive account and shared out. I’ll just send youthe link and you should be able to open it and save it locally to use for different inputs.

although as I recall, google always tried to mess with it when I shred it out and someone opened it up...don’t remember the specifics but seems like it wouldn’t work after downloading.

I’ll send two links - one to the file saves in my Google Drive folder and one to it saves in my OneDrive folder. Between the two of them, you should be able to get a good workable spreadsheet.
 

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Discussion Starter · #6 ·
Thanks

Well in all honesty I just drive locally 95% of the time. But I do like the comfort of knowing it could still be drove on a vacation or road trip if needed.
If it turns 2,500 rpm’s at 70mph I don’t figure that’d hurt anything on a road trip.
 

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The Bacon Hauler (‘12 Cop Charger)
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Well in all honesty I just drive locally 95% of the time. But I do like the comfort of knowing it could still be drove on a vacation or road trip if needed.
If it turns 2,500 rpm’s at 70mph I don’t figure that’d hurt anything on a road trip.
Gas mileage is all that will be hurt, probably lose a couple three MPGs over what you get on highway now
 

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Charger 392
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It is one of the best mods you can do IMO for acceleration. Does not give more hp but a lot more torque to the wheels and you will feel the difference in the seat. I have the 3.91, same Getrag that goes in the 2011 Charger MOPAR 11 from the factory with the NAG1. Will not hurt anything but gas mileage. You will get a few less mpg.

For the 2010 you will need the axles and the Getrag for the swap. Hubs are Ok You will also need a Tune for the TCM to change the gear type, Diablo programmer can do this. 2015's and above do not need a tune and can just change out the diff and go.
 
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