I have a 2007 GMC Savana 1500 AWD with 5.3. I am having a issue with my 4l60e transmission where it doesn't shift as good as the other gears. It takes off in 1st just fine but when shifting into 2nd it seems to be delayed. I thought it was slipping at first but it doesn't seem to rev up but once the shift starts it stays around the same RPM until it shifts. When it does shift it doesn't jerk into gear or anythin. I usually baby it and let off the gas slightly between shifts and that makes it shift fine. If I floor it it seems to shift a little better as if pressure it helping. Down shifting into 1st and second is perfect. I changed fluid and filter and flushed it. Normal magnet buildup but no chunks. Fluid was darker than I liked. I hooked it up to a Matco Scanner and got the following info. Commanded Gear 1, Engine RPM 546, PC Solenoid Actual Current .99 amps, PC Solenoid Duty Cycle 58.20 %, PC Solendoid Ref Current ,97 amps, TNT Sensor 2.44 V, TP Indicated Angle 6.87 %, Trans Fluid Temp 172.4 F, 1-2 Shift Error .40 seconds, 1-2 Shift Time .23 Seconds, 1-2 Solenoid ON, 1-2 Solenoid Open/Short GRD NO, 1-2 Short to Volt NO, 2-3 Solenoid ON, Torque Converter Efficiency .95 :1, Transmission OSS 0 RPM, Slipping 0. Any help on this would be greatly appreciated.

 

This may not help much but no one else has answered so... I've got a 4T65E in a 2003 Impala 3.4L. You've already done the first thing I did when I began to have the problem of not shifting into gear at all. Oil and filter change helped for a month but it came back. So I did the TransGo shift kit which is not difficult, just take the pan off. That also helped for a while. I don't know if they make one for your trans but probably. Went on to replace the solenoids and wiring harness under the side cover. A little more involved but again, only helped for a while. Finally, sprung a huge leak from the torque converter. Got a rebuilt TC from Florida and it's been good for a year or so now. Still, at 298K, the clutches aren't in the best shape but she's still on the road.

 

Having 300k on the clutches is an achievement. Lots of vehicles never make it that far so you are doing the right thing, whatever it is.

 

All credit goes to my wife, oilcanhenry, and the way she drives. I did work on the car but ignored the trans for too long. By the way, I'm prepping this car to move to PA and withstand the safety and emission inspections there. The safety inspection looks intense! In our county in GA we have neither. So I'm going to need lots of luck.