Used 2018 GMC Sierra 1500 transmission – (AT), 4x4, 6.2L, 8 speed (opt M5U)

Year & trim-specific price guide

Used 2018 GMC Sierra 1500 Transmission(AT), 4x4, 6.2L, 8 speed (opt M5U) prices

Trim-specific pricing for the (AT), 4x4, 6.2L, 8 speed (opt M5U) variant of the 2018 GMC Sierra 1500 transmission, built from 44 real salvage yard listings with condition grade detail.
Price summary

A used 2018 GMC Sierra 1500 transmission ((AT), 4x4, 6.2L, 8 speed (opt M5U)) costs $2,000 to $3,885, with a median asking price of $3,055. Based on 44 priced salvage yard listings across the US, updated Aug 18, 2026. Prices exclude shipping, core charges, and installation.

Grade A (excellent)$3,110
Grade B (good)$3,055

2018 GMC Sierra 1500 transmission — (AT), 4x4, 6.2L, 8 speed (opt M5U) price snapshot

USD
Low
$2,000
Average
$2,937
High
$3,885
44 priced listings used · last updated Aug 18, 2026· How we price·

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Reporting price for 2018 GMC Sierra 1500 Transmission ((AT), 4x4, 6.2L, 8 speed (opt M5U))

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Condition comparison

Price by part grade

Grade AClean / low wear$2,500$3,55015 listings
Grade BStandard used$2,188$3,88524 listings
Grade CVisible wearUpdating
Grade XUngraded$2,000$2,5005 listings

Median by grade

Grade price comparison

Median asking price by seller-reported condition grade · $2,000$3,885 overall range

Trim-specific context

How does the (AT), 4x4, 6.2L, 8 speed (opt M5U) compare?

This pricing covers the (AT), 4x4, 6.2L, 8 speed (opt M5U) variant of the 2018 GMC Sierra 1500 transmission, based on 44 priced listings. Its $3,055 median is 16% above the 2018 GMC Sierra 1500 transmission overall median of $2,642.

There are 13 other transmission variants available for the 2018 GMC Sierra 1500.

Pricing is not a fitment guarantee. Match the VIN, part number, engine or drivetrain, and seller-listed variant before ordering.

Same year, other trims

What other 2018 GMC Sierra 1500 transmission variants are available?

Back to full guide

2018 GMC Sierra 1500 transmission — all trims

Common questions

2018 GMC Sierra 1500 transmission ((AT), 4x4, 6.2L, 8 speed (opt M5U)) FAQ

How much is a used 2018 GMC Sierra 1500 transmission ((AT), 4x4, 6.2L, 8 speed (opt M5U))?

Based on 44 priced salvage-yard listings, a used 2018 GMC Sierra 1500 transmission in the (AT), 4x4, 6.2L, 8 speed (opt M5U) variant lists between $2,000 and $3,885, with a median asking price of $3,055.

Which years use the (AT), 4x4, 6.2L, 8 speed (opt M5U) transmission?

In our current dataset, the (AT), 4x4, 6.2L, 8 speed (opt M5U) variant appears only for the 2018 model year.