GMC Sierra 2500 owners have reported 1 problem related to emission control (under the engine and engine cooling category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of GMC Sierra 2500 based on all problems reported for the Sierra 2500.
The truck has several broken exhaust manifold studs that are completely rusted out causing failure of correct emission controls through the catalytic converter, and out of the headers instead. This is environmentally unfriendly, and is really annoying as the exhaust leaks from under the hood due to lack of bolts on the exhaust manifold.
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all problems of the 2002 GMC Sierra 2500
🔎.