2010 3.5l. How did transmission fluid get on top of the automatic transaxle?

TRANSMISSION IS SLIPPING.TIME FOR TRANSMISSION FLUID AND FILTER CHANGE IF CAR HAS OVER 100000 MILES .CHECK UNDERNEATH CAR AND SEE IF TRANSMISSION OIL PAN IS WET OR LOOK LIKE PAN GASKET IS LEAKING.YOU NEED TO REPLACE TRANSMISSION FILTER AND FLUID.YOUR TRANSMISSION DONT HAVE FILLER TUBE YOU HAVE TO ADD A PINT AT A TIME AND REMOVE CHECK PLUG ON TRANSAXLE LOCATED NEAR THE PAN ADJACENT TO THE ENGINE OIL DRAIN PLUG.THIS IS A DANGEROUS PROCEDURE YOUR CAR HAS TO BE LIFTED UP IN THE AIR ON A LIFT. CAR HAS TO BE LEVEL AND ENGINES HAS TO RUN FIVE MINUTES FOR TRANSMISSION TO BE IN OPERATING TEMPERATURE. ONCE TRANSMISSION GET OPERATING TEMPERATURE REMOVE THE CHECK PLUG.IF NO FLUID COME OUT YOU NEED TO ADD MORE FLUID NO MORE THAN A PINT AT A TIME.IF FLUID POUR OUT CHECK PLUG HOLE YOU HAVE TOO MUCH FLUID IN TRANSMISSION.IF FLUID DRIP A SLOW DRIP YOUR FLUID LEVEL CORRECT.TO ADD FLUID YOU REMOVE THE VENT FILL PLUG ON TOP TRANSAXLE WHERE DIP STICK USED TO BE LOCATED.YOU CAN DO THIS JOB YOUR SELF.YOU NEED TO BE ON LEVEL SOLID GROUND AND YOU NEED JACK STANDS AND A FLOOR JACK. LIKE I SAID THIS IS A DANGEROUS JOB AND YOU NEED ABOUT 12M SOCKET TO REMOVE TRANSAXLE CHECK PLUG.

sounds like the main seal is leaking and needs to be replaced.

c...

the transmission fluid goes down the dip stick hole ,either use a small funnel or special tranny fluid refill top up bottle

LEVEL CHECK Check the automatic transaxle fluid level at least every 15,000 miles or 12 months. The dipstick can be found on the left (driver) side of the engine compartment. The fluid level should be checked only when the transaxle is hot (normal operating temperature). The transaxle is considered hot after about 20 miles of highway driving.

1. Start the engine, set the parking brake, and put the transaxle selector lever in the P position.
2. Move the selector lever through all the positions and return to the PARK position. DO NOT TURN OFF THE ENGINE DURING THE FLUID LEVEL CHECK.
3. Remove the dipstick, wipe it clean and then reinsert it firmly. Be sure that it has been pushed all the way in. Remove the dipstick again and check the fluid level while holding it horizontally. With the engine running, the fluid level should be in the cross-hatched area.
4. If the fluid level is below the crosshatched area (engine hot), add MERCON® III automatic transaxle fluid through the dipstick tube. This is easily done with the aid of a funnel. Check the level often as you are filling the transaxle. Be extremely careful not to overfill it. Overfilling will cause slippage, seal damage and overheating. Approximately 1 pint of ATF will raise the fluid level into the cross-hatched area. The fluid on the dipstick should always be a bright red color. If it is discolored (brown or black), or smells burnt, serious transaxle troubles, probably due to overheating, should be suspected. A qualified technician should inspect the transaxle to determine the cause of the burnt fluid. Fig. 1: Automatic Transmission dipstick location - Continentals
   Fig. 2: The dipstick is easy to read and well marked. Do not add if level is in the crosshatch area
   

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Drive the vehicle long enough for the transmission to reach normal operating temperature.
Step 2
Park the vehicle on a flat surface.
Step 3
Let the engine idle with the transmission in park.
Step 4
Locate the automatic transmission dipstick. It will be in the front of the engine compartment attached to the transaxle assembly.
Step 5
Remove the dipstick and read the fluid level it should be between the MIN and MAX mark.
Step 6
Add automatic transmission fluid if the level is low. Place a funnel in the dipstick tube and add as much fluid as need. Do not fill over the MAX mark.
Manual Transaxle Step 1
Park the car on a level surface and wait until the engine is cold.
Step 2
Lift the vehicle according to instructions listed in the owner's manual and support with jack stands.
Step 3
Remove the belly pan from underneath the engine/transaxle by removing the screws on the rear edge and disconnecting the hooks in the front.
Step 4
Locate the check/fill plug on the side of the transaxle.
Step 5
Clean the area around the check/fill plug.
Step 6
Remove the check/fill plug
Step 7
Use a hand pump attached to a manual transmission fluid bottle to pump fluid into the check/fill plug hole, until fluid begins to seep out of the hole.
Step 8
Reinstall the check/ fill plug.
Step 9
Reinstall the belly pan. Insert the hooks on the front edge of the belly pan into the holes on the vehicle's frame. Then reinstall the screws that support the rear edge of the belly pan.

use a very small funnel placed into the dipstick tube check frequently with the dipstick so you don't overfill

This is the procedure for check the fluid level if you have a automatic transmission, I hope this helps.

Be sure that transmission fluid temperature is at least 104° F (40° C). Models with 2.2L engine: To access check/fill plug: In the engine compartment, remove clamp from air hose behind cooling fan. Separate air tube from the hose and push the tube back towards the transaxle. Remove the clip holding the two power steering lines together. All Models: From underneath vehicle remove the transaxle check/fill plug with engine running. Fluid level should be even with hole. Add fluid as needed until fluid flows from hole. Replace check/fill plug and torque to 9 ft. lbs. (12 Nm).

Transmission
fluid
Motorcraft SAE
75W-90 gear oil
(non-synthetic)
Manual transaxle 3.0 quarts
(2.87L)3
Motorcraft FNR5
Automatic
Transmission
Fluid
5–speed
automatic
transaxle
7 quarts (6.7L)4
Premium
Automatic
Transmission
Fluid
6–speed
automatic
transaxle
7.4 quarts
(7.0L

1. Drive the vehicle until the fluid temperature reaches normal operating the usual temperature [80-90°C (176-194°F)]. 2. Place the vehicle on a level floor. 3. Move the selector lever sequentially to every position. This will fill the torque converter and hydraulic system with fluid, then place lever in "N" (Neutral) position. 4. Before removing the dipstick, wipe all contaminate from area around the dipstick. Then take out the dipstick and check the condition of the fluid. The transaxle should be overhauled under the following conditions. a. If there is a "burning" odor. b. If the fluid color has become noticeably blacker. c. If there is a noticeably excessive amount of metal particles in the fluid. 5. Check to see if the fluid level is in the "HOT" range on dipstick. If fluid level is low, add automatic transaxle fluid until the level reaches the "HOT" range. Transaxle fluid: GENUINE HYUNDAI ATF SP-II, DIAMOND ATF SP-II or AUTRAN MMSP-II. Low fluid level can cause a variety of abnormal conditions because it allows the pump to take in air along with fluid. Air trapped in the hydraulic system forms bubbles which are compressable. Therefore, pressures will be erratic, causing delayed shifting, slipping clutch and brakes, etc. Improper filling can also raise fluid level too high. When the transaxle has too much fluid, gears churn up foam and cause the same conditions which occur with low fluid level, resulting in accelerated deterioration of automatic transaxle fluid. In either case, air bubbles can cause overheating, and fluid oxidation, which can interfere with normal valve, clutch, and servo operation. Foaming can also result in fluid escaping from the transaxle vent where it may be mistaken for a leak. 6. Be sure to examine the fluid on the dipstick closely.