Someone school me on gears...

[medicbear]

I know the basics you change gears based on your tire size essentially and what you need the vehicle to do.. And the higher the number on the gears the more times the driveshaft rotates to turn the wheel one time... OK thats where I end.. I know that if i wanna run anything higher than 33's on my JK since it is a DD that I will need at a minimum 4.10 but preferably higher... OK with that being said here is what i need to learn.. What do you need to do a gear swap? Where can you get em besides purchasing? IE: Donor vehicles? What to look for on used gears? What do you need to change em out? How do you change em? Is it easier to put a new rear end in? what kind of vehicles can those be gotten through? Do you need to change anything on the driveshafts? What do lockers do that regular 4x4 doesnt do? I know it makes me sound like a complete noob but in some areas I am and we all were at one point... Thanks

[theyeti1775]

I know the basics you change gears based on your tire size essentially and what you need the vehicle to do.. And the higher the number on the gears the more times the driveshaft rotates to turn the wheel one time... OK thats where I end.. I know that if i wanna run anything higher than 33's on my JK since it is a DD that I will need at a minimum 4.10 but preferably higher... OK with that being said here is what i need to learn.. What do you need to do a gear swap? Where can you get em besides purchasing? IE: Donor vehicles? What to look for on used gears? What do you need to change em out? How do you change em? Is it easier to put a new rear end in? what kind of vehicles can those be gotten through? Do you need to change anything on the driveshafts? What do lockers do that regular 4x4 doesnt do? I know it makes me sound like a complete noob but in some areas I am and we all were at one point... Thanks

I assume your talking about upgrading the JK.
Personally I would look at 4.56's. That's enough that even if you go to 35's you should be fine, but low enough that it won't be too much for 33's. Regearing isn't to be tried by the faint of heart either.

But is yours the Manual or Automatic? That might affect some opinions for it.

For used, I would look around for someone that is planning on '1 tonning' their JK and buying their old set if it has a better gearing that you want.

For XJ's/YJ's/TJ's the cheap upgrade for us 6cyl folks was to buy a set of axles off a 4cyl of the same model. Instant 4.10's with bolt in wrenching.

[medicbear]

my JK is a manual... As far as finding someone whos 1 ton-ing it that could prove hard as it seems only a very few are doing that with their JK probably about as many as are doing hemi swaps... i know at a minimum i could i find a cheap set of 4.10s cause i think i have 3.27s right now... i think the largest i would go would be 35s but more than likely ill prolly run a 33 or a 285..

[MACH04TJ]

Be careful when buying used gear sets. The reason is that those gears have been worn in to that particular axle they came from. Putting them into a new/different axle will most likely cause a diff pattern in the gears. You may end up having problems because of that.

Try looking on pirate 4x4 in the tech section. There is a great write-up on gears and installs.

Mat

[JavaTee]

I'll try to answer a few of the questions the others didn't get to.

I know the basics you change gears based on your tire size essentially and what you need the vehicle to do.. And the higher the number on the gears the more times the driveshaft rotates to turn the wheel one time... OK thats where I end.. I know that if i wanna run anything higher than 33's on my JK since it is a DD that I will need at a minimum 4.10 but preferably higher... OK with that being said here is what i need to learn.. What do you need to do a gear swap? A shop, patience, someone who has the knowledge, experience to teach/help you.Where can you get em besides purchasing? My first choice would be to buy the gearing you want new. IE: Donor vehicles? You need to do a comprehensive search on axles & vehicles as to what they have, and the gearing the have from the factory What to look for on used gears? The ONLY time I would purchase used gears is if the person didn't use them, and they are still in the box. What do you need to change em out? If this is your first time, take it to a shop that specializes in axles/drivetrain because one wrong measurement, and the problems compound rapidly. How do you change em? Mostly simple hand tools, there are a few unique pullers, magnetic caliper, torque wrench, etc. Is it easier to put a new rear end in? If it's the same type, meaning swapping a Dana 44 for a Dana 44, then yes. Sometimes different make/models mount differently, so some fabrication might be needed. what kind of vehicles can those be gotten through? (Look back up to Donor vehicles) Do you need to change anything on the driveshafts? If you keep the same type of axle, then no. Maybe if it's a different axle type, Dana 44 to Ford 9", or 8.8. What do lockers do that regular 4x4 doesnt do? http://www.offroadlockers.com/works....9b5/a89f/.html Check out Aussie lockers website. I know it makes me sound like a complete noob but in some areas I am and we all were at one point. Yeap, we all have been there, and I hope these answers helped... Thanks

Later, T.J.

[Tiff]

I prefer 4.88 with my 6 speed manual, 35's. ('06 LJ) Makes a real differnce on the highway on the hills in Missouri. Better gas milage too, about 2-3 miles/gal. I wouldn't go the use route, too many other things relie on the gears, could cause a ripple effect if something goes wrong. It's very important to get the gears installed exactly right for the spacing. This is the backbone of the foundation, buy new, buy good and have them installed by a professional. No changes needed in DS or lockers.

[BomberJeep]

I dunno the used route isnt all that bad. Sometimes you can find a gem and all you gotta do is just spruce it up a little bit. I know I would rather pay 3-500 bucks or so for some axles out of a 4 popper TJ instead of paying 1500+ for a regear. That 1000 bucks can be put toward say a super 35 or a locker for the front or something else.

[theyeti1775]

I dunno the used route isnt all that bad. Sometimes you can find a gem and all you gotta do is just spruce it up a little bit. I know I would rather pay 3-500 bucks or so for some axles out of a 4 popper TJ instead of paying 1500+ for a regear. That 1000 bucks can be put toward say a super 35 or a locker for the front or something else.

Yeah but he only has that option if he finds a donor rubicon with the JK.
I had the option on a YJ and it cost me $50 for the D30/D35 with 4.10s. Not a bad upgrade from a D30/D35 with 3.07s.

[USMCHarleyJeepGuy]

Randy's Ring & Pinion has a kick ass book on everything to do with gears and gearing from breaking it down Barney-style all the way to installs.

[medicbear]

sounds like 4.56 or 4.88 is the ticket... 4.56 for dd up to 35" forget about 6th gear... 4.88 will hurt the mpg a lil bit or wanna tow but necessary if i wanna go any bigger but i doubt that will happen i dont forsee goin any bigger than 35" max simply cause i cant afford it lol