The average asking price for a used 2018 GMC Sierra 1500 Crew Cab is $30,544, with 78,381 miles on average, across 35 cars for sale at U.S. dealers as of Nov 10, 2026.
Used 2018 GMC Sierra 1500 Crew Cabs for sale at U.S. dealers ask $30,544 on average (half ask less than $30,590), across 35 cars. The cars for sale have 78,381 miles on average: one with fewer miles is worth more, and one with more is worth less. To check one car's price against cars of its trim and mileage, enter its VIN in OttoQuest's free Deal Check.
The 2018 asks $30,544 on average with 78,381 miles; the 2017 asks $28,580 with 78,750 miles, and the 2019 asks $31,213 with 89,279 miles.
Used and certified cars for sale at US dealers, each car counted once. Days listed are the dealer’s own days on market where they publish it. Price moves compare the same cars at both ends of the window.
| 6 |
| 2013 | $21,057 | 95,293 | 3 |
