How do I know
 

if my solenoid pack is with variable delay or not? The part numbers are different I want to get the right one.

I wish I could help you Chuck. I've never run into that problem before. The only "variable" solenoids I know of are for the torque converter clutch and electronic pressure control. The 95-97 trucks had an on/off TCC solenoid while the Super Duty trucks had a pulse width modulated TCC apply solenoid. I wasn't aware of any differences in the EPC solenoid valve.

I would assume if the difference is due to the TCC solenoid, then you would want the one that IS NOT variable.

420E Solenoid Assembly, E4OD (NonPWM).... 1 95-Up 36420B 31A-110A


420E Solenoid Assembly, E4OD (Non PWM) (w/ Variable Delay)......................................... 1 95-Up 36420C

This is what the parts breakdown PDF shows. Pm me your email and I will send you the whole pdf. I only knew there was a differance in the E4OD and 4R100 for the PWM.