charging issue/slight display pulsing/flickering

[biggsteve97]

The volt gauge in my 2003 Tahoe sometimes drops from just above 14 volts down to roughly 11-12 volts and also has a slight flicker/pulsing to the PRNDL, info center, and Climate control displays. Ironically the radio and dash light are night affected. I replaced the alternator last September and installed a new instrument cluster 2 months ago. I honestly do not remember when this started but I do know the pulsing was there before I replaced the cluster. I read a tsb once on a feedback issue from the alternator harness plug that might cause transmission shifting issues and was wondering if that might have something to do with it. I do occasionally have a 1-2 shift issue, when it shifts it hangs 1-2 seconds between releasing first and engaging second. At one point there was also a loud "clack" sound from 1-2 at wot shifts. I believe that to be a worn or broken 1-2 accumulator piston and that should also explain the shifting issue. Any ideas on the pulsing issue.

[usmcchevy]

Anybody?

[Jacfourteen]

My 01 tahoe does the same thing sometimes when I let off the gas it will drop below normal idle RPM and the lights will dim for just a second then it will kick back up and act normal. Hope someone has ideas....