Rear transmission seal

if you are talking about the automatic transmission front seal, then you will have to remove the driveshaft, and then remove the transmission, in order to remove the seal from the front of the transmission, this is a timely job, and care has to be done in replacing the seal in, order to get it started straight , take a large socket or seal installation tool, or a piece of a wood 2/4, and hammer, and gradually tap the new seal inward till it bottoms out, then re install the transmission, and driveshaft , and start vehicle up and check fluid level, and you should be ok.

There are seal drives . you might be able to get one at your local parts store . they may loan or rent this type of tool to you . Just ask them when you buy the seal or the gasket kit .Now to replace the seal you will need to remove the transmission to gain access to the rear main seal

Yes just remove shaft and old seal and replace new seal with a piece of wood while tapping the wood all around the seal enenlt so you don't damage the new seal. Hope this helps.

Remove the transmission, after holding the rear of the engine supported, using a jack with a piece of wood between it and the engine. Remove the clutch and pressure plate, and the flywheel or if automatic, the flex plate. The rear main seal retainer will then be exposed. Remove the 2 oil pan to main seal retainer assembly, and the bolts circling the retainer, and slide the retainer assembly unit back off the crankshaft. Remove the old gasket from the retainer, and clean the gasket ridge before installing a new gasket. It's a one piece hard rubber gasket, which must be inserted in the retainer evenly. This can be done on a work bench, or flat wood on a concrete floor, Some light oil might help it seat easier, Once seated slide the retainer containing the new gasket back over the rear of the crankshaft, A rubber hammer will help ease it back into position, Replace all bolts, not forgetting the oil pan to retainer bolts, and reinstall all parts in reverse order of removal. If a manual trans, this would be an excellent time to install a new clutch kit.

it sounds like you have a tail shaft seal gone in the transmission it's not a difficult fix if you are handy. Remove the drive shaft and remove the tail stock seal(there are install and removal tools but a hammer and a screwdriver will remove it nicely)then replace with new seal (if you don't have the install tool a 5" long piece of 2x4 and a hammer works BE GENTLE!!!!)and reinstall drive shaft..........these seals are available at your local auto parts store and are usually no more tan $10.00
hope this helps!.........good luck!