I had a 94 LT1 automatic and changed the transmission fluid & filter regularly myself. I never had any problems. It is possible that you need a new pan. All of the pan bolts should be torqued when servicing is done. If not, it will crack, distort, and/or lead to breakage. The torque specification for the pan bolts is 97 In. Lbs. and use a light Locktite on the bolts to prevent loosing. As you can see, that is not very tight.
Your leakage problem could just be the pan is being tightened too much & it's squeezing the pan gasket out from behind the mating surfaces. If the pan was over tightened a lot, then the pan at the bolt holes could be distorted. The holes would look like they are dimpled instead of being flat. If the pan is distorted, you could try hammering them flat but there's no guarantee that would work. Also, make sure the fluid level is not too high when the car is warmed up.
Are you sure its the pan & not the front seal? Drop the flywheel cover & check to see if leakage is coming down from the front seal, on to the leading edge of the pan & then blowing back in the wind from the car's movement.
|UPDATED|8/3/2015 8:48:10 AM (AZT)|/UPDATED|
______________
Rts-LT4
Hals94