INSTALLING A TORQUE CONVERTER SEAL

I'm not sure about what gasket to check, but I've always left my manual tranny's connected to the transaxles and removed the axles at the transaxle. This made simpler by popping the ball joints out, thus allowing the hub assembly to swing away. Hope this helps.

you will need to remove transmission...Can be big job sometimes...

If the leak is between the engine and the transmission, yes.
Its also called a front pump seal on some models.

Front Pump Seal that the Torque Converter goes into?

You have to remove the transaxle to do that

This seal is located in the front of the transmission. Its called a front input shaft seal. You will need to drop the transmission and remove the torque converter. Once the converter is off if you look at the shaft protruding from the transmission just at the base of the input shaft you will see this seal.
you can rent a seal remover from you parts store, IE Autozone or Oriely's and rent the seal installer tool. This will insure that you do not damage the seal housing or the seal when installing the new one.
One word of advice would be to take the torque converter to a transmission shop and have it checked before reinstalling it. If it has a worn seal face or has a bad set of blades you would be money ahead to replace it while your doing it the first time and not have to pull it back apart 3 months later.

The transmission is not sealed in the v8 I looked up. It's bolted together. Fluid Pan Removal & Installation To Remove:

1. Before servicing the vehicle, refer to the precautions in the beginning of this section
2. Raise and support the vehicle
3. Place a drain pan under the transmission fluid pan
4. Remove or disconnect the following:
   • Drain plug and drain the fluid
   • Shifter cable bracket NOTE: The transmission fluid pan gasket is reusable, clean and inspect for damage; if not damaged, the gasket should be reused.
     
   • Fluid pan and gasket
   • Transmission fluid filter
   • Clean and inspect the transmission fluid pan and magnet
   • Converter housing access plug
   • Converter drain plug

To Install:
NOTE: A new converter drain plug must be used to prevent leakage.

1. Install or connect the following:
   • Install the converter drain plug. Torque to 89 in-lbs (10 Nm)
   • Install the converter housing access plug
2. Lubricate the seals and install the transmission fluid filter. Torque the bolts to 89 in-lbs (10 Nm)
3. Install the oil pan magnet in the transmission fluid pan NOTE: The transmission fluid pan gasket is reusable, clean and inspect for damage; if not damaged, the gasket should be reused.
   
4. Install the transmission fluid pan and gasket and loosely install the screws.
5. Using a crisscross sequence, torque the screws to 8 ft-lbs (11 Nm)
6. Install the shifter cable bracket. Torque bolts to 18 ft-lbs (25 Nm)
7. Install the drain plug. Torque to 19 ft-lbs (26 Nm) NOTE: It will be necessary to hold the drain plug (larger plug) with a wrench when removing the fluid level indicator plug.
   NOTE: Use 3/16 inch Allen key to remove the fluid level indicator plug. Remove the fluid level indicator plug.
   
8. Verify the transmission fluid level

Did you make sure the torque converter was properly seated on the input shaft of the transmission. In oder to do this you need to spin the torque converter and push it into the transmission so as to spline the torque converter into the input shaft of the transmission. Be patient and keep spinning and pushing and it will spline up.

Dont waste your time and money trying to use a transmission stop leak product, they don't work on large leaks, you say the leak is excessive in this case the you must remove the transmission to access and remove the torque converter, after you have removed the torque converter carefully inspect the torque convert imput shaft for wear and also you will need to visually inspect the transmission front pump bushing for wear also, I have seen it all to often people just replace the seal thinking it was just a seal failure, well more times than not there is a reason for seal more than just the age of the seal, excessive wear on trans pump bushing and torque converter imput shaft is usaully the cause, check and repair those as good practice during this repair unless you just like to do the repair over again for free... also check the torque converter run out, sometime when they are repaired they are welded back together somewhat crooked which will cause it to spin off of a true center, this will cause immediate damage to transmission. Check also your engines crankshaft end play for looseness this can cause wobble which will transfer to transmission causing this problem as well... do the repair thouroughly and who ever does it for you have them check all that I listed and you should get a good repair which will last without issues.... please rate my help thanks...

its actually pretty easy if you have the basic tools needed and a little mechanical knowledge, because i dont think you can buy just the bearing at a auto parts store. they sell you the whole hub assembly which is great for the DIYer.

lift the car off the ground and block it from rolling and place a jack stand under it so it cant fall on anyone.


Wheel Bearings

• REMOVAL & INSTALLATION

Removal & Installation

These vehicles are equipped with sealed hub and bearing assemblies. The hub and bearing assemblies are non-serviceable. If the assembly is damaged, the complete unit must be replaced.

1. Before servicing the vehicle, refer to the precautions section.
2. Remove or disconnect the following:
   WARNING DO NOT allow the caliper to hang unsupported from the brake hose.
   
   
   Front wheel Halfshaft nut and washer Caliper from the steering knuckle and support it aside
   
   
   Brake rotor Anti-lock Brake System (ABS) connector, if equipped 3 hub/bearing assembly bolts Halfshaft from the hub/bearing assembly Hub/bearing assembly
   
   Fig. Exploded view of the front hub/bearing assembly
   
   

To install:
Install or connect the following:

Hub/bearing assembly onto the halfshaft, making sure the splines engage smoothly Hub/bearing assembly to the steering knuckle. Torque the bolts to 70 ft. lbs. (95 Nm). Anti-lock Brake System (ABS) connector, if equipped Brake rotor Caliper onto the steering knuckle. Torque the bolts to 38 ft. lbs. (51 Nm). Halfshaft nut. Torque the hub nut to 284 ft. lbs. (385 Nm) on nuts colored black, or 173 ft. lbs. (235 Nm) on gray colored nuts. Front wheel. Torque the nuts to 100 ft. lbs. (140 Nm).

here is a diagram on how to replace the front pinion seal.
please do not forget to rate and comment about your experience with fixya.

1. Before servicing the vehicle, please familiarize yourself with safety procedures.
   
2. Remove both half shafts.
   
3. Mark propeller shaft and pinion flange for installation reference.
   
4. Remove front propeller shaft.
   
5. Rotate pinion gear three to four times, to verify pinion rotates smoothly.
   
6. Record pinion flange rotating torque with an inch pound torque wrench for installation reference.
   
7. Hold flange with Holder 6719 and four bolts and washers.
   
8. Remove pinion nut.
   
9. Remove flange with Remover C-452.
   
10. Remove pinion seal with a pry tool.
    Removing the companion flange
    Measuring pinion rotating torque
    Pinion seal installer
    Tightening the pinion nut
    

To install:

1. Apply a light coating of gear lubricant on the lip of pinion seal.
   
2. Install seal with Installer C-3972-A and Handle C-4171.
   
3. Install pinion flange onto the pinion with Installer C-3718 and holder.
   
4. Hold pinion flange with Holder 6719A.
   
5. Install new pinion nut and tighten nut until there is zero bearing end-play.
   
   CAUTION Do not exceed the minimum tightening torque when installing the companion flange at this point. Damage to the collapsible spacer or bearings may result.
   
6. Tighten pinion nut to 271 Nm (200 ft. lbs.).
   
   CAUTION Never loosen pinion nut to decrease pinion bearing rotating torque and never exceed specified preload torque. If preload torque or rotating torque is exceeded a new collapsible spacer must be installed.
   
7. Record pinion flange rotating torque, with a torque wrench. Rotating torque should be equal to the reading recorded during removal plus an additional 0.56 Nm (5 inch lbs.).
   
8. If rotating torque is low, tighten pinion nut in 6.8 Nm (5 ft. lbs.) increments until rotating torque is achieved.
   
   CAUTION If maximum tightening torque is reached prior to reaching the required rotating torque, the collapsible spacer may have been damaged. Replace the collapsible spacer.
   
9. Install propeller shaft with reference marks aligned.
   
10. Install half shafts.