The 8.1L GMT800 fan upgrade owners actually run: the 9-blade Duramax fan (GM 15010202 / ACDelco 15-80690) on the 2008–2009 TrailBlazer thermal clutch (GM 25816289 / ACDelco 15-40144). Verified part numbers, why the bolt patterns force the pairing, what the catalogue data proves about fitment — and the clearance check you cannot skip.
GMT800 8.1L Duramax Fan & TrailBlazer SS Fan Clutch Upgrade Read Post »
A cylinder-specific misfire on a 2014 Sierra 1500 5.3L L83, worked through the ignition system in order — plug, spark, wire, coil, connector, wiring — to confirm a bad ignition coil before replacing anything.
Chevy 5.3 Misfire Coil Test — Find the Bad Coil Before Buying Parts Read Post »
The DPF on LMM and later Duramax trucks is only a problem when it’s neglected or when something upstream is failing. How regens actually work, the habits that keep the filter healthy, and when cleaning beats replacement.
Duramax DPF Maintenance: Regens, Cleaning and Keeping It Healthy (and Legal) Read Post »
DEF-era Duramax ownership means NOx sensors, DEF pumps and derate countdowns. What actually fails on LML and L5P trucks, how to diagnose it by code instead of guessing, and the habits that prevent most of it.
Duramax DEF System Problems (LML & L5P): NOx Sensors, DEF Pumps and Derates Read Post »
The CP4 high-pressure pump is the LML Duramax’s defining risk: little warning, and a failure that sends metal through the whole fuel system. What causes it, the signs, and the protection options owners actually use.
LML Duramax CP4 Pump Failure: Why It Happens and How Owners Protect Against It Read Post »
The LB7 Duramax’s injector failure is the defining problem of the 2001–2004 trucks. How to spot it early, confirm it with balance rates instead of guesswork, and do the repair once instead of twice.
LB7 Duramax Injector Failure: Symptoms, Diagnosis and Repair (2001–2004) Read Post »
On 1998–2007 GM 4x4s, the transfer case oil pump slowly wears a hole through the magnesium case — fluid leaks out and the case is scrap. A pump brace kit installed during a fluid change prevents it. Here’s how to check yours and fix it before it fails.
GM Transfer Case Pump Rub: The $100 Fix That Saves a $1,500 Case (1998–2007) Read Post »
A lying fuel gauge on a GMT800 has exactly two usual suspects: a sulfur-contaminated sending unit in the tank, or the cluster itself. Guessing wrong costs a fuel pump drop or a cluster repair for nothing. Here’s the check that decides it.
Silverado Fuel Gauge Wrong or Erratic: Sending Unit vs Cluster (1999–2006) Read Post »
That clicking behind your Silverado or Tahoe dash is a blend door actuator with stripped gears. Here’s how to identify which of the several actuators failed, replace it, and — the step everyone skips — run the relearn.
Chevy Blend Door Actuator: Clicking Dash Diagnosis, Fix and Relearn Read Post »
Most 1996–1998 Vortec 5.7 no-starts come down to one number: fuel pressure. The CSFI poppet injectors physically stay closed below roughly 50 psi. Here’s the test, the spec, and when the spider upgrade makes sense.
1996–1998 Vortec 5.7 Hard Start or No-Start: CSFI Fuel Pressure Diagnosis Read Post »
