I have been driving the wife’s 1999 3.8 LTZ this week and on occasion notice a little slippage/chatter in first gear. If I accelerate smoothly, I don’t notice the problem. If I accelerate a little harder, I notice the slippage/chatter sometimes. It reminds my of the traction control issue I had a while back. Sometimes the traction control light came on. I had it in the shop for the rear brake lights. The service manager said a high pressure code in the transmission was set but they couldn't find anything wrong with it. He checked because I asked about the traction control. Is there a service bulletin for this or am I getting ready to have a transmission repair bill? I am thinking the latter. Anyway, I don't notice any burnt smell in transmission. I change fluid at recommended times. Fluid is normal on dip stick. No leaks. I have right about 98K on the car now.