• BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
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  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
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  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
  • BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD - Stateside Performance - Tonneau Covers - Hard Fold - BAK - BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD
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BAK448121

BAK

BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD

BAK BAKFlip MX4 Hard Folding Bed Cover - 6 ft 6 in Bed, Matte Finish | 2015-2019 GMC Sierra 3500HD

$1,249.99 USD
$1,249.99 USD
Sale Sold out
Shipping calculated at checkout.

In stock

The BAK BAKFlip MX4 (GEN 3) fits the 2015-2019 GMC Sierra 3500HD 6ft 6in bed and delivers a hard folding tonneau with 22 percent stronger panels than the previous generation.

Install Difficulty: DIY Possible
Clamps to factory bed rails with included hardware; typically installs in 30-45 minutes with two people.

Product Overview

The BAKFlip MX4 is built from heavy-duty aluminum top panels and side rails, reinforced with high-density polymer cores for a 22 percent strength increase over the original.

A patented auto-latching system secures the cover on close, and re-engineered lock components improve resistance to forced entry versus GEN 2.

EPDM rubber perimeter seals and a 13 percent longer dual-action tailgate seal keep water out while preserving factory tailgate function.

Features & Specifications

  • Fits: 2015-2019 GMC Sierra 3500HD
  • 6ft 6in bed length fitment
  • Hard folding aluminum panels with polymer cores
  • 22 percent stronger panels vs original MX4
  • Patented auto-latching system secures on close
  • Re-engineered locks resist forced entry
  • EPDM rubber perimeter seals block seepage
  • 13 percent longer dual-action tailgate seal
  • Sits flush with bed rails, matte black finish

Fitment

This part fits the following vehicles:

Year Make Model Submodel
2015-2019 GMC Sierra 3500 HD Base
2015-2019 GMC Sierra 3500 HD Denali
2015-2019 GMC Sierra 3500 HD SLE
2015-2019 GMC Sierra 3500 HD SLT
⚠ Submodel Fitment: If your submodel is not listed in the fitment table above, we cannot confirm fitment. Please contact us before purchasing to verify.

Shipping & Returns

Tracking is typically provided within 3–5 business days; items shipping direct from the manufacturer may take 5–7. Some items are made to order or may be backordered. Questions about stock? Reach us through live chat or email.

Warranty

All warranties are through the manufacturer and are facilitated by Stateside Performance. Some manufacturers require the end user to contact them directly; in that case we will point you to the right contact. Email us with any warranty questions.

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  • Free shipping over $250

    Free shipping applies to items that are shipped via ground through UPS or FedEx and are over $250 going to the continental 48 states. This does not apply to Alaska or Hawaii, and does not apply to any item(s) that are shipped via freight or with any other option other than ground shipping.

    Shipping policy 

  • 30-day returns

    Returns must be requested within 30 days of delivery. Parts must be new, unused, uninstalled, and in original packaging, with an RMA. Some items are final sale.

    Return policy