the engine on the 1994 525i is the 2.5 liter l6 same as the 1994 325i the only difference thats noticeable is the oil pan iknows there is more but i just cant see it. i had to change the whole thing because i had a serious oil leak located in that part. it was not the seal i changed that too.it was almost like it couldn hold the pressure when i accelerate the car it leaks even worse.