One problem related to automatic transmission cooler has been reported for the 2008 GMC Acadia. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 GMC Acadia based on all problems reported for the 2008 Acadia.
While merging onto the highway the vehicle was revving up, but not speeding up. I would take my foot off the accelerator for a second and then try to accelerate again. The gear would sometimes "catch" and sometimes not "catch". The mechanic discovered that the one cooling line was corroded and another was "sweating". The transmission, torque converter, and cooling lines all had to be replaced. I think its a premature time for my vehicle to need a new transmission with only 76k miles as the vehicle is well maintained.