Well i have seen very few detailed threads on the Kia Sportage Gear change. Many folks haven't even really seen the inner workings of their differential. For someone who is tackling the project for the first time, it can be a little overwhelming. But this thread should give you a good in indication of what you need to go. For those not in the know, the Kia Sportage 4x4 models contain a 4.78 gear ratio for their final drive. Just so happens that the front differential is the same size as the FB, miata, s2000 and some other models. Best part is, use first gen RX-7 folks can directly bolt the 3rd member in place of our existing on on the 84-85 big bearing axles. It is an open type differential though so generally swapping an LSD unit is a good idea.

Here are two good parts fiches to give you an idea of what parts are in here and what they are called.






Required Tools:
12mm Socket
14mm Socket
Hammer
Dial Indicator (Harbor Freight or similar ones will work fine)
Magnetic Base for the Dial Indicator (again, Harbor Freight works)
Torque Wrench
Helps to have air or electric impact
Tool to rotate be bearing adjustment screws
Right Stuff (for sealing diff into housing)

Required Parts:
GSL or GSLSE 3rd member, 1984 - 1985 models for its LSD or have another LSD available.
Kia Sportage 3rd member 94, 96-01 model years

Step 1: Obtaining and disassembling your Kia Sportage Axle

The absolute first thing you need to find is a Kia Sportage third member from the front differential. They are a common vehicle, so if your lucky a local yard should have one. Typically, they will just pull the entire front axle. Its not a large piece, but still nothing you want to stuff on your motorcycle to get home. Just make sure you dump the diff fluid out. Its should consist of an aluminum axle housing and a cast iron third member. See Picture below:



Once you get your Kia axle home you can start to remove the 3rd member. I recommend laying out some cardboard or plastic to catch any diff fluid that will come out. First, remove the 4 bolts holding the long side axle in. Use your hammer and give the axle some taps until it breaks free. Then slide the axle out. Add it to the scrap pile or sell it or place it on your coffee table as a conversation piece. They choice is yours, but from here on out, you don't need it.

From here you can start removing the 3rd member from the aluminum housing. Two of the bolts holding the 3rd member in are 12mm. Rest are 14mm. Save all of these bolts as you will reuse them later.

Will the bolts removed, again use the hammer to break the 3rd member free. Once free, lift the piece out of the housing. You should now have an empty axle housings and a 3rd member. See pictures below.

Step 2: Disassembly

Once you have your 3rd member out, you should clean off the white gasket sealer material. You will be remaking the gasket later so you don't want any old material causing problems.



Now for the fun part. Get the Kia rear onto your work bench. You will see that there are four 14mm bolts holding down the bearing caps and two 12mm bolts holding down retainers for the adjusting screws. Do not loosen the 14mm cap bolts yet! Start by removing the 12mm bolts holding the retainers. Once the retainers are removed, set the aside. Keep track of everything you remove and which side it came from. You will be reinstalling everything in the same place (more or less). With the retainers gone, you can now remove the pre load from the bearings. This can be done by rotating the right side (if facing internals) adjusting screw counter-clockwise. Mazda does not give good insight on their bearing loads. Peejay has determined it to be equivalent to 2-1/2 holes. This will make sense you see the adjusting screws.

Once unloaded, you can remove the 14mm bearing cap bolts. Then remove the bearing caps and set them aside. Now, you can remove your Kia sportage ring gear / differential unit. For those that are removing their LSD from an Rx-7 3rd member, repeat the above process. Those with an aftermarket or a pre-pulled unit continue on.

Begin removing the ring gear bolts. An impact will make this easier if you have it. Else, you might have to resort to bracing it in a vise and doing by hand. But if you have the impact, air or electric, use it. Back these out carefully. leave one or two still a little threaded. You will have to tap them to get the ring gear to slide down. Once the ring gear has dropped, remove the last two bolts, and then the ring gear itself. Again, for those removing the LSD from an Rx-7 3rd member, repeat this process.





Something that is interesting to see with the differential and ring gear removed, is the pinion. Both rings are 7" but the pinion diameter is what gives you your gear ratio. As you can see the Kia Sportage has a considerably smaller pinion. This does directly relate to the power the rear axle can handle. The small pinion is going to have a lower yield point than the 3.90 pinions. But odds are if your making tons of power, your not going to be looking to overly high gear ratios anyway.

Step 3: Reassembly

Now for the fun part. Getting all back together. Take the LSD unit from the Rx-7 and attach the ring gear from the Kia Sportage to it. Reuse the Kia's ring gear bolts. Ring gear bolts will need to be torqued down to 51~61 ft-lbs (75~85 N/m).

the forum is crashing out, ill finsih it later. i cant post more than two sentences. cant even post a single sentence. will be cont. on a separate thread. ####ing crap server.

nice write up... tut perhaps a weekend job?

Right on, Whizbang! Man, I want to bring drinks and visit your garage!
This is the exact same setup I have in my IT-A race car and it works great. (Actually, had to do it twice since I blew one up mid-season.)

i simply can not post more information. the server wont let me. i even typed out one sentence and the server nixed it. But i can type this... i dont get it

Same issue I was going through with my long replies last week hahaha. For some reason, just one tiny little group of words made the whole thing unpostable, and I discovered that by breaking it apart and posting different parts of it separately, and then that one sentence STILL wouldn't post, for no discernible reason whatsoever.

Great info though.

what would it cost to get another server to run this site! i would almost considering paying for it!