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Re-gear of rear differential for base + 33" tire upgrade

mC.242

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I'm getting the base 4dr with the 2.3L/AT (most likely) but was wondering if a lower rear ratio will be necessary to go up to 33" tires.
Stock is the open diff 3.73.

I'm not asking if it would be better to do it, more along the lines of is it necessary and approximately what's the cost.
I'm fairly mechanically inclined and would do it myself, just not that familiar with modifying/upgrading rear diffs.
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I'm getting the base 4dr with the 2.3L/AT (most likely) but was wondering if a lower rear ratio will be necessary to go up to 33" tires.
Stock is the open diff 3.73.

I'm not asking if it would be better to do it, more along the lines of is it necessary and approximately what's the cost.
I'm fairly mechanically inclined and would do it myself, just not that familiar with modifying/upgrading rear diffs.
I would do both; if not you may shell both your front and rear diffs. Additionally, leave this to the professionals. If there is one thing I do not tackle myself that is electrical and gears. Gear swaps have to be precise with pinon depth and backlash. Not only that you need the right tools. Cost would be about $1500 if you bring in the diffs to a mechanic and honestly I think if you only go 33s you will be fine. Just my two cents.
 

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Is the pumpkin big enough for a regear?

I remember this being an issue with base Jeeps in the past.
 

Broncocito

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Is the pumpkin big enough for a regear?

I remember this being an issue with base Jeeps in the past.
I would first see if there are aftermarket gears and that will give us the answer.
 

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I'm getting the base 4dr with the 2.3L/AT (most likely) but was wondering if a lower rear ratio will be necessary to go up to 33" tires.
Stock is the open diff 3.73.

I'm not asking if it would be better to do it, more along the lines of is it necessary and approximately what's the cost.
I'm fairly mechanically inclined and would do it myself, just not that familiar with modifying/upgrading rear diffs.
For starters, you have to replace both front and rear gear sets on a 4x4.
Because they work together when the 4x4 system is engaged.

Secondly, bad news.
The open differential ring gears are welded to the differential.
Not bolted.
Only the locking differentials have bolted on ring gears.
This is a carryover from Ranger production, as it cheaper and faster than bolting.

Because of these two factors, you will have to replace both front and rear gear sets, and differentials at the same time.

For the ratio with 33" tires, 4.46 is the standard ratio.
4.7 is the performance set. Which is what comes on the Badlands.
 

Broncocito

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For starters, you have to replace both front and rear gear sets on a 4x4.
Because they work together when the 4x4 system is engaged.

Secondly, bad news.
The open differential ring gears are welded to the differential.
Not bolted.
Only the locking differentials have bolted on ring gears.
This is a carryover from Ranger production, as it cheaper and faster than bolting.
Welded in, that sucks.
 

Broncocito

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Dana is the OEM maker.
The 4.46 and 4.7 ratio sets will be available almost instantly for the Bronco.
I know it is Dana; however he has the smaller diff. Not sure if they have them, but then again I have not researched that.
 

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I know it is Dana; however he has the smaller diff. Not sure if they have them, but then again I have not researched that.
Stock ratios ( which is all you need for 33" tires) will be available since that's rolling down the production line at the same time.

It's the deeper than factory (5.13, 5.38) that may take a year or two to show up.

ETA: I apologize, I should have been more clear on what factory stock and aftermarket ratios are.
 
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mC.242

mC.242

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U can just get Sasquatch and not worry about it :)?
Trying not to go overkill on what will be a daily driver/family adventure vehicle.
 
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mC.242

mC.242

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For starters, you have to replace both front and rear gear sets on a 4x4.
Because they work together when the 4x4 system is engaged.

Secondly, bad news.
The open differential ring gears are welded to the differential.
Not bolted.
Only the locking differentials have bolted on ring gears.
This is a carryover from Ranger production, as it cheaper and faster than bolting.

Because of these two factors, you will have to replace both front and rear gear sets, and differentials at the same time.

For the ratio with 33" tires, 4.46 is the standard ratio.
4.7 is the performance set. Which is what comes on the Badlands.
Interesting. Sounds like I won't be doing any of this myself.
But if the standard gears are fine with 33's I'll just leave it be.
 

elseminoleguapo

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Suppose you go base but manual. Then you've got 4.46 gears already. Too much for the axles to go 33s if you're planning on doing some off roading?
 
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mC.242

mC.242

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Suppose you go base but manual. Then you've got 4.46 gears already. Too much for the axles to go 33s if you're planning on doing some off roading?
No MT available on the 4dr base.
 

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The open differential ring gears are welded to the differential.
This may just be a terminology thing but there's no way the ring gear is welded to the differential. It may be welded to the CARRIER which keeps the ring gear and spider gears lined up inside the diff. But that entire assembly could be removed and replaced. Hell, looks like ARB already has an air locker (replaces the carrier) for the m210 and m220. May just need to wait for them to develop an install kit for the Bronco.

Edit: Doesn't look like there's an air locker for the m190 ... yet ....
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