I need an expert opinion. My 99 Chevy Tahoe with a 5.7L V-8 has a hard shift into second under slow/traffic type driving. If I do a higher speed acceleration, I don't feel it. What the heck is it? The car has had 91K easy miles on it and almost no towing at all. It gets careful use by a good owner. I am changing the trans fluid this week to smooth it out I hope and lubricating the drive shaft. Any ideas? Cost? New trans? AAmco any good? I am a car dealer but I am stumped. Thanks for the help....
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I've seen something called a shift solenoid referred to in this forum. Not sure if that might be your problem. Someone here w/ knowledge of your year can probably help.