I have a problem with my 94 f-350. Something is happening to make it go into fail safe mode (light for od switch flashing coupled with very hard shifting). My question is when this happens does it generate a code that can be checked with scanner? I have had two people try to pull codes one with snap-on scanner and one with mac and neither could tell me what was causing tranny trouble.
thank-you for any help you can give me
Dave

 

Get your own code scanner, its worth it. For a '94, you can use a $20 one from any big auto parts store.

My E4OD did the same thing. It was the torque converter clutch slipping, a common problem in this transmission. The pressure regulator solenoid could also be bad, a cheaper problem. When the TC clutch slips, the computer tries to compensate by maxing out the pressure, resulting in very hard shifts.

Try and find a good independent transmission shop by referrals. Just stay away from Aa***.

Jim