Excellent 4.9 | 18,452 reviews

BAKFlip MX4 GMC Sierra Hard Folding Tonneau Cover - BAK-448130

BAKFlip MX4 GMC Sierra Hard Folding Tonneau Cover - BAK-448130

$862.99
$862.99 $1,149.99
SAVE 24% Sold out
BAKFlip MX4 GMC Sierra Hard Folding Tonneau Cover - BAK-448130

BAKFlip MX4 GMC Sierra Hard Folding Tonneau Cover - BAK-448130

$862.99
$862.99 $1,149.99
SAVE 24% Sold out

BAKFlip MX4 GMC Sierra Hard Folding Tonneau Cover - BAK-448130

Sleek, secure, and durable–what else could you want? The bakflip-MX4 tonneau cover is a top-of-the-line hard-folding cover engineered for maximum aesthetics, weather resistance, and security.

The bakflip-MX4 is constructed entirely from alloy materials, including heavy-duty aluminum top panels and side rails.

Unlike comparable soft-folding tonneau covers, you can't simply slice through the MX4 with a pocket knife.

No matter the cargo in the bed, you can rest assured that your gear's protected by a premium bed cover from BAK industries

Features
  • Heavy-duty aluminum construction

  • Sleek matte-black finish

  • Extra-strong prop rod clips for a secure hold

  • Folds toward the bulkhead for 100-percent bed access

  • Premium rubber bumpers protect the cab when folded into the upright position

  • Simple no-drill installation

  • Weather-resistant EPDM seals and end caps

  • 400-lb. Weight capacity
What our Experts Think
  • Premium MX4 hard-folding protection system
    The BAKFlip MX4 (BAK-448130) is a heavy-duty aluminum tri-fold tonneau cover for GMC Sierra, designed for maximum bed security with a clean, low-profile OEM look.
  • Upgraded durability over G2 platform
    Built with reinforced aluminum panels and high-density foam core, offering improved rigidity, scratch resistance, and long-term structural strength compared to earlier BAKFlip models.
  • Strong cargo-ready load capacity
    Supports up to ~400 lbs of evenly distributed weight, making it practical for light rooftop or in-bed cargo when closed.
  • Full bed access folding design
    Tri-fold system allows you to drive with the cover closed, partially open, or fully folded against the cab, enabling flexible hauling without removal.
  • Enhanced weather sealing system
    Integrated seals and tailgate design help reduce rain, dust, and road debris intrusion, improving all-weather usability.
  • Low-profile, OEM-style appearance
    Sits flush inside bed rails for a factory-integrated look that improves aerodynamics and reduces wind noise.
  • Secure tailgate locking integration
    Locks automatically when the tailgate is closed, creating a hidden, theft-resistant storage solution for daily use or work gear.
  • Easy no-drill installation
    Clamp-on rail system enables fast installation and removal without permanent vehicle modification.
  • Ideal for Sierra owners needing balance
    Best suited for users who want strong security, weather protection, and full bed versatility without moving to bulky roll-up or one-piece covers.
Q&A

Q: What is this product?
A: The BAKFlip MX4 is a premium hard folding tonneau cover designed for GMC Sierra and Chevrolet Silverado trucks, offering strong bed protection, security, and full access flexibility.

Q: What vehicles does it fit?
A: It fits GMC Sierra 1500 and Chevrolet Silverado 1500 (new body style), commonly for 5'8"–5'9" bed lengths depending on configuration.

Q: What makes the MX4 different from other tonneau covers?
A: It uses reinforced aluminum panels with a matte finish, upgraded seals, and improved latching hardware for better durability and weather resistance.

Q: Can I access the full truck bed with it installed?
A: Yes. The cover folds up against the cab, giving 100% bed access without removal.

Q: How strong is it?
A: It is rated to support up to about 400 lbs of evenly distributed weight when closed.

Q: Is it weather resistant?
A: Yes. It includes perimeter seals and a dual-action tailgate seal to help reduce water, dust, and debris intrusion.

Q: Does it lock for security?
A: Yes. It automatically latches and locks with the tailgate, helping protect cargo from theft when closed.

Q: How is installation done?
A: It uses a clamp-on, no-drill installation system designed for a secure fit without permanent modification.

Q: What is the main advantage of the MX4?
A: It combines heavy-duty aluminum construction, full bed access, and improved weather sealing, making it one of the most popular premium folding covers for Sierra owners.


Maintenance Tips
  • Regular cleaning: Wash panels with mild soap and water only; avoid harsh chemicals to protect the matte aluminum finish and seals.
  • Inspect weather seals: Check perimeter and hinge seals for wear or gaps to maintain water resistance in all conditions.
  • Keep rails clean: Remove dirt, leaves, and debris from side rails to ensure smooth folding and proper sealing.
  • Clamp & hardware checks: Periodically re-tighten mounting clamps and bolts to maintain secure no-drill fitment.
  • Hinge lubrication: Apply light, non-gumming lubricant if folding becomes stiff or noisy over time.
  • Panel care before folding: Ensure panels are clean and dry before folding to prevent scratches or wear between sections.
  • Drainage maintenance: Keep drain channels and tubes clear to prevent water buildup in the truck bed.
  • Latch function test: Regularly confirm automatic latching panels engage properly when the cover is closed.
  • Load caution: Do not exceed rated weight capacity (evenly distributed) to avoid panel or hinge stress.
  • Seasonal inspection: Recheck seals, alignment, and hardware after extreme weather or long trips for optimal performance.
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