One problem related to manifold/header/muffler/tail pipe has been reported for the 1997 GMC Jimmy. The most recently reported issues are listed below.
A/c compressor failures other- intake manifold coolant leak due to use of plastic intake manifold master cylinder failure (loss of pedal/leal). Replaced master cylinder short time later same problem and dealer reported failure of anti lock computer at cost of $1200. 00. Repair refused and after a few weeks had them recheck master and they replaced the unit. No problem several months later.