2020 GMC Sierra 1500 Pre-Purchase Inspection Checklist
Known Issues — 2020 GMC Sierra 1500
CRITICAL
2.7L Turbo I4 timing chain rattle on cold start
CRITICAL
AFM/DFM lifter failure on 5.3L and 6.2L V8
MODERATE
8/10-speed transmission rough shifts
MODERATE
Carbon buildup on 2.7T direct injection engine
MODERATE
3.0L Diesel DEF system sensor failures
MINOR
MultiPro tailgate electronic latch issues
What to Inspect
- On 2.7T — listen for timing chain rattle cold start
- On 5.3/6.2 V8 — check for AFM lifter tick
- Test transmission shift quality cold and hot
- On Diesel — check DEF system for fault codes
- Test MultiPro tailgate all positions
- Check 4WD engagement
Expected Maintenance Costs
| Service | Interval | Cost |
|---|---|---|
| Oil change (synthetic) | every 7,500 miles | $80-$120 |
| Transmission fluid service | every 45,000 miles | $200-$350 |
| Spark plugs (V8) | every 60,000 miles | $200-$350 |
| Rear differential fluid | every 45,000 miles | $100-$150 |
| DEF fluid refill (Diesel) | every 10,000 miles | $30-$60 |
| Transfer case fluid | every 45,000 miles | $80-$130 |
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