Hello I just bought a 1994 s420 with a 120k miles on it. When i shift the car into reverse there seems to be a 2 second delay. Is this normal? If not , what should i look into, thanks.

Bass

 

not normal.

the brake band 3 (which is actually a clutch) lip seal on the piston is leaky. this is on the front part of the transmission and not difficult to change. only the b3 works on reverse gear.
this is an early sign of worn out transmission. if the piston lock comes off, the damage is severe.

the other possible problem will be on the valve body. this is quite complicated for you to do since some modification must be done which involves restriction of counter pressure, or reducing bore diameter.