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Rear Axle Ratio Questions

Fly by Nite

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So let's say someone got a Base - 2.7 - 10A setup. What would going to 32 inch tires do with the stock gear ratio? Also, same question but with Sasquatch going down from 35s to 32s? (Can you tell I want 32s?)
Just calculate the percent change:
Difference between stock 30" tires and 32" = 2 inches
2 inches divided by the original 30": =0.0666... or 6.7 percent change.
For the auto, 3.73 original ratio >>> 3.73+ 6.7% = would need 3.98 gears to keep the rpm at same speed with 32" tires
Or, it would act like: 3.73-6.7%= 3.48 gears and 30" tires
At 60 mph you would have to drive: 60 + 6.7% = 64 mph to keep the same rpm as the original 30" tires.
So..... it's not a big deal, especially with a 10 speed auto..... there's likely to be a perfect gear for any speed.
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Haystack

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At first I was worried about the base auto only having 3.73 gears. After pondering it for a few days, I decided to check out the Ranger forum since they come with the 2.3/10 speed auto/3.73 gears. I noticed a lot of guys upgrading to 265/70r17 (same size as a BD, 32ish). I didn't see any complaints about lack of power or anything regarding this size with the 3.73 gears. I did see a few people say their speedos were spot on accurate now compared to the stock size.
 

kodiakisland

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In this specific case, the gear ratios on the auto are lower than for the manual (not counting crawl gear), so you can have a higher geared axle. Plus the work of the torque converter.

Compare the first 5 gears or so on the auto and you can see it's continually lower geared coming up to speed.

Ford Bronco Rear Axle Ratio Questions 1597913122792
 
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kodiakisland

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I know nothing about this particular transmission. If the crawl gear is synchronized then yes you should be able to. If nothing else you should be able to double clutch it to get it to work.
 

Fly by Nite

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A 32 to 46" tire is a 43.75% difference.
That would make your 6.588 crawler gear feel like a 3.7 ratio. So yeah, it would be driveable.
 

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In the latest info that came out, reviews stated that to use the crawler gear you must come to a stop and lift some sort of ring to be able to shift it into C ... so ratio wise.. sure.. but reality wise... I don't know if you could physically start off in C and shift up.
 

Treeza61

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LOL. I was just referring my experience that a dollar is harder earned (and consequently goes a bit farther) in the landlocked West than on either the West or East Coast.

Those are the same reasons that matter to me, however being a skier and habitual winter traveler, and having a job which requires me to still show up on bad weather days when others might not, heated seats are a plus. Not a necessity, but something I'd pay for. As such, I'd probably spring for mid package anyway since the safety tech adds some real value over the life of the vehicle. None of the rest of the "luxury" features matter to me, and I can get mid package pretty much regardless of which trim I select.

I agree the jump from BD to BL steep. I keep thinking I can justify $3k, maybe $4k of that stuff if I count the nifty gimmick of not having to manually unbolt a sway bar. It's a lot of expensive off road gadgetry to haul around when as you say, Black Diamond gets you 90% of the way there.
Don’t forget about the headlights.
 

Karl_in_Chicago

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A 32 to 46" tire is a 43.75% difference.
That would make your 6.588 crawler gear feel like a 3.7 ratio. So yeah, it would be driveable.
Except . . . not for long, LOL. I imagine the weaker parts of the stock drivetrain get a vote here, too, and one of them is going to quickly opt out of that situation. ? Accelerate + 46" tires + stock axles & U-joints/CV-joints, etc = BOOM!
 

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Don’t forget about the headlights.
The headlights are cool, but not something I'd put money down on even if they were available a la carte. As long as the base headlights are bright enough (and they should be, I've never met OEM LEDs that weren't).
 

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Ride Em Bronco

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Still trying to decide if I want BB or OB (if 2-dr OB is available in manual) and if I want lockers at all. So if the 4.46 Manual has the optional 4.7 Electronic-locking Front and Rear Axle (Sasquatch), is my understanding correct that the 4.46 gear ratio only changes to the 4.7 gear ratio when the lockers are being used?
 

The Pope

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Still trying to decide if I want BB or OB (if 2-dr OB is available in manual) and if I want lockers at all. So if the 4.46 Manual has the optional 4.7 Electronic-locking Front and Rear Axle (Sasquatch), is my understanding correct that the 4.46 gear ratio only changes to the 4.7 gear ratio when the lockers are being used?
If you get the optional 4.7 Electronic-locking Front and Rear Axle, you will have the 4.7 Gear no matter if the axles are locked or not.
 

Ride Em Bronco

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If you get the optional 4.7 Electronic-locking Front and Rear Axle, you will have the 4.7 Gear no matter if the axles are locked or not.
That makes my decision of staying with the BB easier - since most likely will not be off-road and want to keep the gear ratio at 4.46 for highway. Besides not sure if OB will even be available with manual. Thx for reply Pope - you saved me some coin. :)
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