I have a 91 F-150 5.0L with 168000 miles. The rear seal is leaking all over the transmission. I was wondering what is require in order to change it.

 

Pull the motor or pull the trans. An auto is easier because you can slide it back just enough to work in there.

 

so, what your telling me is that i dont have to pulll the motor apart to fix this problem.

 

The tranny would be the easiest way. Raised the vehicle from the front for added room and clearance. Disconnect neg on battery, remove starter, driveshaft, shift linkage, speedometer cable and anything else attached to the tranny. Remove crossmember bolts and tranny mount bolts. You will loose some tranny fluid out of the tail shaft when you take out the driveshaft, so put a pan under it to catch it, Then put a ziplock bag over it with tape to keep from making a mess when moving the tranny around. Remove the bellhousing bolts and dipstick tube. Use a floor jack and a piece of plywood about 3/8" the size of the pan and lift the tranny up enough to remove mount and crossmember. You need at least 2 people for this job, makes it much easier. Slowly lower the tranny and disengage from the engine by pulling back on it. When it's fully disengaged, you can lower it completely and pull it out of the way. Be careful cause the tranny is kind of tipsy on the floor jack.
If you have the 1 piece seal on the engine, get a #8 sheet metal screw, drill a 1/8" hole in the seal(steel ring part) and thread in screw. Using a pair of pliers to grip the screw, put a screwdriver under the pliers and pry against the engine block to remove the seal. Clean seal recess and install new seal. Also, get some carb/choke cleaner and clean the front of the tranny housing by the torque converter real good before installing. When removing tranny, try not to turn the shaft, this will help make it easier to reinstall without have to realign it. Reverse procedure for reinstall, start engine, check for leaks and service tranny to proper level. Hope this helps.

 

You may want to make sure it isn't the oil pan gasket leaking first. They tend to leak in the rear and appear just like a rear main seal leak. Normally if the oil is leaking down the front side of the transmission and down over the inspection cover it's the oil pan gasket. If the leak is all coming out of the plug in the bottom of the trans it would be ther rear seal.