There is a fix for the 6 speed shifter rattle on 97 and early 98 cars. The 6 speed shifter rattle should not be confused with the gear rattle that is common to 6 speeds when starting in first gear from a stop. If you have the shifter rattle you know what it is and won’t confuse it with the gear rattle. Chevrolet has an updated shifter assembly part no. 1256-0342. The break point for the new shifter assembly is model year 98 VIN 101534. The price of the new shifter assembly is $220.65. It can probably be done under warranty but I bought it and installed it myself because I’m disgusted with my dealer’s knowledge and service. The new shifter assembly has a rubber bushing added in the front trunion shaft bushing to dampen vibration. The old assembly had a rubber bushing in the rear trunion shaft bushing only.

I also installed Mallett’s billet aluminum shifter. It is more precise than the stock shifter because the rubber isolation in the shift lever is eliminated. It also has a little shorter throw because the total length of the lever and knob is shorter. And the clunky stock shift knob is replaced with a small aluminum one similar to a formula car. I highly recommended it. You’ll find yourself doing upshifts and downshifts when you don’t need to just for the fun of it.