I have a 92 d250 and sometimes when i start it up in the morning the speedometer doesn't work and thus the O/D won't work either. but usely it will kick back in a few miles down the road. it's been having this problem off and on for a few years. I put a new TPS on it about 2 years ago and it didn't help the next thing i'm going to do is replace the VSS. If anyone has been having the same problem and fixed it it would help me out alot if you could lead me in the right direction. Thanks

God Bless Texas and John Wayne

 

Look at the drive gears for the VSS while you have it out.

 

Well i got the speedometer problem fixed but now the truck is jumping in and out of 3rd and O/D bad now any suggestions. i'm thinking maybe the O/D solenoid. i'm getting a little ****** with it.

God Bless Texas and John Wayne

 

I'm guessing a TPS adjsutment is in order....but I row my gears. Here's your bump--TTT

 

What he said - on both counts.