The GM Service Guy

Oil Change Maintenance Guide for GM Vehicles (Chevrolet, GMC, Buick & Cadillac) Oil changes are the single most important piece of maintenance on any GM vehicle — and the easiest...

Knock Sensor Replacement: Meaning, Symptoms & Repair Guide for GM V8s Knock sensor codes on GM V8 trucks are extremely common — and in the vast majority of cases, the...

Engine Misfire: Meaning, Symptoms & Repair Guide for GM Vehicles An engine misfire can come from a dozen different root causes — spark, fuel, compression, or even a bad sensor...

6.2L Lifter Replacement: Meaning, Symptoms & Repair Guide for GM Trucks & SUVs GM's 6.2L L86 and L87 V8s share the same variable-displacement lifter technology as the 5.3L — and...

Oil Pressure Problems: Meaning, Symptoms & Repair Guide for GM Engines Low oil pressure is one of the few engine problems that genuinely can't wait — running an engine on...

Timing Chain Replacement: Meaning, Symptoms & Repair Guide for GM Vehicles A stretched timing chain doesn't just make noise — it throws off cam timing enough to trigger correlation codes,...

A dirty throttle body is one of the cheapest and easiest fixes for a rough idle or hesitating GM engine — and one of the most overlooked pieces of routine...

Rear Main Seal Leaks: Meaning, Symptoms & Repair Guide for GM Vehicles A rear main seal leak is one of the most expensive "small parts, big labor" repairs on a...