GMT800

What oil and how much for your GMT800’s 4.8, 5.3, 6.0 or 8.1 Vortec — the capacities, the factory weight, and when a heavier oil actually makes sense.

A GMT800 pan-drop and filter service is the cheapest transmission insurance you can buy. Here’s the fluid, the capacity, the interval and the mistakes that kill a 4L60E early.

Brake lights stuck on, no brake lights, cruise that won’t set, or a shifter stuck in park on a GMT800 often trace to one cheap part — the brake light switch at the pedal.

A window that grinds, drops into the door, or moves crooked on a GMT800 is a failed regulator, not always the motor. Here’s how to tell them apart and what to buy.

Sweet smell, foggy glass and a wet passenger floor mean a leaking heater core on a GMT800. Here’s how to confirm it, and what the job actually involves before you tear the dash apart.

An ABS light on a GMT800 is usually a wheel speed sensor — and up front, that sensor lives inside the hub bearing. Here’s how to find the bad corner before you throw parts at it.

EVAP codes on a GMT800 usually start at the cheapest part — the gas cap — and work toward the vent and purge solenoids. Here’s the order to check so you don’t buy a canister you didn’t need.

A cold-start tick that fades as the GMT800 warms up is usually a broken exhaust manifold bolt, not a $3,500 lifter job. Here’s how to tell them apart before you panic.

That clunk when you turn the GMT800 wheel is almost always the intermediate steering shaft. Here’s the real fix versus the grease band-aid, plus when it’s actually a worn idler or pitman arm.

A GMT800 that cranks but won’t start is usually fuel, spark or security. Here’s how to check fuel pressure the right way and stop guessing before you drop the tank.