zzzzzzzzzzzzzzzzzzzzzzzzzz the GM DEXRON III IS a fluid that creates acid @20K miles, change the fluid and filter . use DEXRON VI [6] .. gm DUMPED III in 2006.. old GM died in 2008 lost billions ,,,. because of recall failures. now if the transmission works after the fluid change .. then change the fluid again after a few hundred miles. valves in the tranny stick ..I used transmedic additive on my old GM vehicles no issues. ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ