Thanks for taking the time to help out.


I'm doing a gear swap in the near future, but have a ton of questions that I can't seem to get answered because I am getting confused on the google and so new to the gear swapping scene.


Have a 2013 Sahara JKU automatic with 3.21 gear ratio, but upgrading to 35's soon, so thinking 4.10, 4.11, 4.56 or 4.88.


Will be a daily driver doing city driving, some highway, but also driving NY->TX a few times a year, while doing some light over-landing, camping and fishing in precarious locations.

• What gear kit / install kits are compatible with my current 3.21 hardware? What isn't compatible and what would I need to purchase additionally?
  
• Do I need both front and rear done?
  
• Confused on what Dana 30/44 means in relation to changing gears from 3.21
  
• What is a ballpark price range for gear swap? Will be done in the North East US most likely.
  

Thanks and please feel free to provide any insight.

 

Well, I have not changed any of mine.. but there is this chart from another post recently.. Dana 30 is the front Axle on JK-JLs and Dana 44 is the Rear axle. Rubicon has electronic locking..

 

Hearing what shops are charging on the west coast or southern states or midwest will do you no good. $1500ish seems to be about average, but you'll hear about some places charging under a grand out the door, others will be well above the 3k mark. East coast generally seems to be on the higher end of the spectrum for whatever reason. Contact several of your local shops and ask about both the price AND the warranty, as both can vary quite a bit even between local shops. (if you end up buying/supplying your own gears for a shop to install, be sure to ask about changes to the warranty!!!)

D30 and D44 will refer to the size (and strength) of the gears inside the axles. Don't worry about this, let the shop take care of supplying the correct gears and the correct install kits. All you need to do is decide on the ratio. (one note on the d30. There is a carrier break between the 3.21 gear ratio and anything higher. This means that you will need a new open carrier to hold the higher numeric gearset. Roughly $80-90 in addition to the d30 gears. It should be included in the quotes you get, just mentioning in case you see it somewhere and have the question.)

While the axles are torn apart is a great time to add traction (lockers/limited slips), as the labor is basically free. Doesn't really sound like you need them, but again, it's the right time to be thinking about it. (specifically regarding the front d30, any full case limited/locker would be used instead of buying that new open carrier.)

For the correct ratio for you? Judgement call, but check the charts and think about 4.56. A quick google search on anything like "Jeep JK Gear Chart" will bring up plenty of colorful sets of charts, broken down by engine and transmission. Use actual measured tire height, not mfg spec or whatever the sidewall says. (my last set of 35's measured out to 33.5" under vehicle weight and normal inflation psi...)

 

+1 on everything above. The only thing I don't think was explained, unless I missed it, is yes, you have to have matching gears in the front and rear.....or really bad things will happen. That $1500 +/- price would be for both labor and parts for both axles. As mentioned, the price varies by location, and also shop to shop.

 

- that's ok I was just looking for ballpark and was curious to be honest. Will most likely have it done in NE, but spend time in austin and charlotte as well.
- cleared up some major worry there thanks
- checking out quadratec and extreme terrain, what are the "carrier" listed as? not seeing in the ring/pinion section
- toiling between 4.56 and 4.88

 

Lockers are carriers if you are thinking about doing lockers, this is the time to do them. If you are going to be on the highway go with 4.56, if you were in the mountains and did a lot of steep grades then I would go 4.88.

Let the shops get you all the parts so they are right. Shops that do a lot are going to get parts cheaper then you can get and most shops around here don't like customers supplying parts as they screw it up most every time causing delays and more expense. Find a good shop that does a lot of gears and don't just rely on the cheapest quote you get.

Good luck.

 

On quadratec, they are in the Differential Cases & Assemblies section, not the Ring & Pinion section. Try part number 52443.0016 for an open carrier. (prices seem to have gone up on both carriers and lockers since the last time I looked at them...) And check part number 16100.602 for a visual comparison to what a full case traction device looks like instead of that open carrier. (There are gears inside of that case instead of just the open area.)

But not to be a broken record or anything, unless you are doing the install yourself, it is probably better to just let the shop source the parts.

 

This is the best advice in this entire thread.

 

Very interesting explanation