C6 shifting problems.

I bout a 70 Mach 1 with a c6 and it shifts hard from first to second at light throttle and feels like a slow slide in to second almost a slip the has a two three flare at any throttle , any ideas. This car had been sitting for eighteen years . Does the modulator valve
Have any affect

10SHOTS wrote:I bout a 70 Mach 1 with a c6 and it shifts hard from first to second at light throttle and feels like a slow slide in to second almost a slip the has a two three flare at any throttle , any ideas.   This car had been sitting for eighteen years  . Does the modulator valve
Have any affect

Yes the modulator has a affect on shifting I would go ahead and change it and filter/fuild it wouldn't hurt to add some trans medic to it to help with the seals that may have gotten hard. If that don't help pull the trans and get it freshen up.