Hi,

I have a 1996 stock C4 Coupe (70,000 miles) with 4L60E Automatic transmission. The trans usually behaves normally, but once in a while I get what I believe is a missed downshift. This usually occurs when cruising at 50-60 MPH and slowing down to 35-40 MPH for traffic or a turn. If I give it moderate acceleration, it takes a second for the trans to get in the right gear - and by that time, I can be near the red line or on the rev limiter. This occurs infrequently, and has happened more often when taking hard right-hand turns. The fluid level is normal, and I am not getting any OBDII codes that indicate any issue with the trans.

Since this occurs infrequently, it's difficult to diagnose. I had the fluid and filter changed (Chev dealer) about 3000 miles ago. Before I take this in, I'd like some guidance on what the possible issue may be, or how I can best describe the problem. I have looked at some related threads, and have seen references to electrical problems that may contribute to shift problems. As I said, this occurs randomly and infrequently, does not appear related to temperature, and the car is a week-end driver.

 

I would just be sure that none of the electronics have been damaged or nicked by a road obstruction. Think if 2 wires had been slightly bared, then touch, in odd situations.

worth checking...