2013 YukonXL 2 speed Transfer case change to 1 spd

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1stYukonXL

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I'm looking at what's involved to change from the 2 speed transfer case in a 2013 to a single speed and/or changing the existing 3.48 rear end gears to 3.08 for better milage. Anybody had any experience or advice with this?
 

Fless

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Moved you here for more focused potential answers.
 

petethepug

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Welcome from SoCal

I usually see owners swap’g the Denali & Esky AWD xfer case to the single or 2 speed cases. Yes, it can be done.

Obviously this isn’t exactly what you’re looking to do but it will have info and pics on what you’re getting into.

Keep in mind if you change the ratio in the diff at one end of the truck, you’ve got to match the diff at the other end.

The AWD to 4WD swap …


The AWD to 2WD swap …



 
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1stYukonXL

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Welcome from SoCal

I usually see owners swap’g the Denali & Esky AWD xfer case to the single or 2 speed cases. Yes, it can be done.

Obviously this isn’t exactly what you’re looking to do but it will have info and pics on what you’re getting into.

Keep in mind if you change the ratio in the diff at one end of the truck, you’ve got to match the diff at the other end.

The AWD to 4WD swap …


The AWD to 2WD swap …



Thanks for your reply. I don't know why I would want to change the 2 speed part? Just throwing that out there. What I really am interested in is going from the 3.48 to the 3.08 for hopefully better milage? What would be involved in this only?
 

j91z28d1

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Thanks for your reply. I don't know why I would want to change the 2 speed part? Just throwing that out there. What I really am interested in is going from the 3.48 to the 3.08 for hopefully better milage? What would be involved in this only?


unless you do a lot of highway driving on flat roads going down ratio isn't going to help a lot.

city driving guys seem to say going up in gears makes it's accelerate eaiser and might help fuel a bit. but if you're having a shop change both front and back diff gears, it's pretty expensive. I bet it's over 3k$ these days. that buys a lot of fuel.

going to a transfer case with 2wd might help mileage a bit. or maybe even getting rid of 4wd if you don't need it. save the weight, hassle working on stuff and extra drag of the drive line spinning. but again, that's maybe 1mpg?

it's very hard to make a vehicle that gets bad mileage stock get better. easier to make them go faster, much harder to make them more efficient
 

SpareParts

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If I'm driving a vehicle I like and enjoy driving gas mileage is the last thing I'm worrying about as that's just part of the cost of doing what I like.
I seem to be in the minority though.
 

wjburken

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The transfer case has nothing to do with gear ratio. If you simply want to change your gear ratio, you need to change your front and rear differentials.

Do the math on your fuel savings. If dropping down to 3.08 gears lets you go from 19 mpg to 21 mpg, if you drive 20,000 miles a year, that’s a savings of about 100 gals. At $4.00/gal that’s only $400 a year. If you spend $1000 or more on the conversion, you won’t see any savings for almost 3 years. If you drive fewer miles; the longer it will take to pay yourself back.
 
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petethepug

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Thanks for your reply. I don't know why I would want to change the 2 speed part? Just throwing that out there.

Again, much aware you’re not wanting to add a 2SP xfer case. Only wanted to get the process of the swap(s) to you.

Obviously this isn’t exactly what you’re looking to do but it will have info and pics on what you’re getting into.
 

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