I have a 1997 c1500 4.3 4L60E automatic Transmission with an Intermittent PO748.
Transmission rebuilt 2 years no issues till a month ago..
My symptoms are
Intermittent 1-2Harsh Shift at 1st it did ones in a while. I noticed it jerked on the 1st and 2nd shift on driving out of the parking a lot then I parked it and waited a few hours and it was gone on driving then a few weeks ago.i noticed it did it straight for a few weeks with no check engine light on but after that I scan the pick up and It did have the PO748 and 1870 Codes? But still no check engine light on.
I did throw parts at it replaced both Shift Solenoids A and B with the 3-2 and the Pwd not exactly sure on the name but that solenoid too.
I did upgrade the 1-2 accumulator to the sonnax pinless piston. No change in the symptoms it goes by shifting normal to the 1 - 2 hard shifts.
How do I go by diagnosing this without throwing in more parts blindly. If I can't figure it out then I have to find a transmission shop.and take it in. I'm not a mechanic but I'm very mechanically inclined.
Transmission rebuilt 2 years no issues till a month ago..
My symptoms are
Intermittent 1-2Harsh Shift at 1st it did ones in a while. I noticed it jerked on the 1st and 2nd shift on driving out of the parking a lot then I parked it and waited a few hours and it was gone on driving then a few weeks ago.i noticed it did it straight for a few weeks with no check engine light on but after that I scan the pick up and It did have the PO748 and 1870 Codes? But still no check engine light on.
I did throw parts at it replaced both Shift Solenoids A and B with the 3-2 and the Pwd not exactly sure on the name but that solenoid too.
I did upgrade the 1-2 accumulator to the sonnax pinless piston. No change in the symptoms it goes by shifting normal to the 1 - 2 hard shifts.
How do I go by diagnosing this without throwing in more parts blindly. If I can't figure it out then I have to find a transmission shop.and take it in. I'm not a mechanic but I'm very mechanically inclined.