Chrysler Repair: 1994 chrysler new yorker:trans shifting problem, chrysler new yorker, postal mail

Question
Last weekend we changed the oil in my car and cleaned the engine.  Two days later when I was leaving from work my car would not go into reverse.  I was able to finally pull it forward and I could not get it into reverse.  My dad got in and of course it immediately went into reverse, however when I was driving it I could not get it to go above 35mph and it was running 3k rpm's.  We checked the fluid and it was full and it did not smell burnt.  Later that night my husband took it out and it drove fine, he had it up to 60 and it ran fine.  I drove the car for 6 days and this morning it would not go into reverse I had to play with it for about 5 minutes and then I got it into reverse, and on the way home it would not go above 35.  Once again the fluids are fine.  I have had no problems with the tranny before this.  It has 120k miles on it.  Please help!! Thanks

Answer
Hi Kelly,
I am not certain if by "not getting into reverse" you mean mechanically the linkage is feeling strange, or it seems to be in the correct position but just doesn't engage reverse. There is a procedure to adjust the shift cable which is different depending upon whether you have a column or a floor mounted shifter. It would be easier to xerox copy and postal mail that procedure to you, so let me know if you believe that might be the problem and tell me which location your shifter is positioned at.
If you believe the issue is with the internal functioning of the trans then the best thing to do is to have the transmission control computer read out for any fault codes it may have recorded which will give a clue as to what might be wrong. There is a data link connector under the dash just to the right of the steering column. It has a  blue 6-pin plug and it requires a socket that meshes with that. The reader is a Chrysler DRB II or equivalent which you would find at a dealership or an independent trans shop (check first, this plug is NOT the plug that is used to check for engine fault codes, so be very specific to be sure they have the socket and the reader). Ask for the fault code numbers, what they mean, what they say needs to be done, and how much they would estimate the cost to be. Then write back and we can compare that to what the Chrysler shop manual says about those codes.
Roland