Mile ratingNo known defect pattern for this model year
The 2020 GMC Sierra 3500HD is not on our list of model years with a widely reported mechanical or electrical problem. That is a point in its favour, not a clean bill of health — this car's own history still matters, so check the VIN report and get it inspected.
What owners of the 2020 Sierra 3500HD say
Owner reviews for this exact model year are the fastest way to find out what breaks, what it costs to fix and whether the car lives up to the spec sheet.
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About this car
The GMC Sierra 3500HD is No. 7 on the Caboose longevity table: 26.2% of them reach 250,000 miles, against 5.4% of all vehicles. This 2020 GMC Sierra 3500HD SLT Crew Cab 4WD is listed at $40,199, about $3,512 below the CarGurus expected market price of $43,711. It has 126,906 miles and comes in Silver. Power comes from a 6.6L V8 Biodiesel with four-wheel drive. It is offered by Auto Town USA LLC in Caldwell, ID.
Why it's a good buy
- 26.2% of GMC Sierra 3500HDs reach 250,000 miles — No. 7 of 52 on the Caboose table
- 73,094 miles of runway before 200,000
- 8% below market price ($3,512 savings)
- No widely reported defect pattern for this model year
- Steel Wheels
- Bluetooth
Features
Caboose PRO
The full 796-word analysis of this car
The verdict
The 2020 GMC Sierra 3500HD SLT Crew Cab 4WD is listed at $40,199 with 126,906 miles. The Caboose score is 8.5 out of 10, built from three things: how far below market the price sits, how much of the 200,000-mile target is still ahead of the odometer, and how often this model reaches 250,000 miles in the iSeeCars study (26.2% of GMC Sierra 3500HDs do).
The asking price is $3,512 (8.0%) under the CarGurus expected price of $43,711, which is a real discount rather than a rounding gap. That puts it in the top group of cars on this site, so it is worth a same-week inspection before someone else books one.
- Price against the market
- Mileage runway to 200,000
- Odds of reaching 250,000 miles
- Ownership budget (planning estimates)
- What to inspect on this exact car
- Questions for Auto Town USA LLC
- Your next seven days
Get it road-ready
The usual first-week purchases for a 2020 GMC Sierra 3500HD, from partners we trust.
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