First of all i will say, its not a easy job.It requires all tools and vast experience in transmission working procedure/.But if you have this ability, you can replace the transmission.
An automatic transmissions that is acting up may need to be repaired or replaced. Replacement is an expensive option (typically $1800 to $2500 or more!), but in many cases it is the only option unless the problem is relatively minor. Why? Because rebuilding an automatic transmission requires special training, experience and tools.
Most general repair shops and new car dealerships won't even attempt a transmission overhaul in-house. They will replace a bad transmission with one that has been professionally rebuilt by a rebuilder who specializes in transmissions. Many transmission shops do the same thing. It is much faster, easier and less trouble to install a reman transmission than to attempt the job themselves. A reman transmission from a transmission rebuilder or a factory-authorized rebuilder comes with a warranty and is usually pre-tested.
The only other replacement option is to buy a used transmission from a salvage yard. You never know what you are getting when you buy a used transmission, so it is a gamble. Some salvage yards will exchange a transmission they sold you for another if the first one turns out to be no good, but others may not.
Use a floor jack to raise the car off the floor and put jack stands under the front and back of the car to get to the transmission. Make sure the car is well supported and won't fall on you while you take the transmission out.
Loosen the link cables to the transmission and the fluid cables to the radiator. Take the vacuum lines loose from the modulator if the car has one. Use a wrench to remove the two u-bolts from the rear end of the car. Slide the drive shaft away from the transmission.
Take out the speedometer gear assembly and put the transmission jack under the transmission pan. Lift the transmission. Take off the lower bell housing cover. Use a wrench to take off the torque converter bolts, the bell housing bolts, the four cross member bolts and take off the rear transmission mounts. Lift the transmission jack and take the cross member off.
Lower the transmission while you move the transmission jack toward the back of the car. Make sure everything is unhooked and the transmission clears the car.
Take the old transmission off the jack and put the new transmission on the jack. Raise the transmission as you slide it under the car. Hold the torque converter in while you turn it until it clicks.
Put the cross member back on, using a wrench to replace the rear transmission mount, the cross member bolts, the bell housing bolts and the torque converter bolts. Replace the speedometer gear assembly and slide the drive shaft back into the transmission.
Replace the vacuum lines to the moderator if you have one and replace the cable linkage to shifter and throttle valve. Use the floor jack to support the car while you take out the jack stands. Lower the car to the floor and remove the floor jack.
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If you need to change Automatic transmission fluid then this is the procedure:---
Raise the front of the car with ramps or a floor jack. Safely support it with jack stands and wheel blocks. Place a drain pan beneath the transmission drain plug. Use a ratchet or socket wrench, whichever is most appropriate, to remove the drain plug. Wait for the fluid to stop draining.
Loosen the retaining bolts on the transmission fluid pan with a socket wrench. Gently tap the side of the pan with a rubber mallet to break the seal. Support the pan with one hand while you remove the bolts completely. Carefully lift the pan to drain the remaining fluid from the pan.
Check the fluid filter for clogs or damage. Replace the filter if necessary. Clean the pan, gasket and gasket surfaces with a safe solvent and allow them to air dry. Replace the pan and gasket to their original positions. Ensure the bolt holes line up and reinstall the retaining bolts. Progressively tighten the bolts in a criss cross fashion to 7 1/2 to 8 1/2 foot pounds with a torque wrench.
Replace the drain plug and tighten it to 22 to 25 foot pounds. Lower the car and make sure it's on level ground.
Remove the transmission fluid dipstick and replace it with a funnel. Alternate adding small amounts of fresh automatic transmission fluid and checking the fluid level until the fluid level reaches the lower mark on the dipstick. Hyundai recommends the use of Mopar ATF Plus Type 7176 or its equivalent.
Start the engine, let it idle for 2 to 3 minutes and check the fluid level again. Add more transmission fluid if necessary. When the fluid level reaches the appropriate position on the dipstick, replace the dipstick, close the hood and turn off the engine.
