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Peterbilt 379 Frame Crossmembers & Covers

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  • Qty in Cart
  • Quantity
  • Price
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  • Brunner Custom Enclosed Light Bar W/ 8 - 4 In Rnd, 5 - 2 In Rnd LED Lights W/ Square Corners

    Brunner Custom Enclosed Light Bar W/ 8 - 4 In Rnd, 5 - 2 In Rnd LED Lights W/ Square Corners

    BRUNNER FABRICATION

    $1,783.99
    Rear Light Bar W/ 8 - 4 Inch Round & 5 - 2 Inch Round LED Lights By Brunner FabricationIf you are wanting to add lights to your cab, 4 State Trucks offers this high quality Brunner custom enclosed...
    09-021013
    SKU:
    09-021013
    Location:
    Made In USA
    Truck Class:
    Heavy Duty
    Make:
    Universal Items
    Finish Options:
    Polished
    Light Options:
    With Lights
    Material Options:
    Stainless Steel
    Product Type:
    Frame & Chassis
    $1,783.99
    Qty in Cart: 0
    Price:
    $1,783.99
    Subtotal:
  • Smooth Aluminum Wide Big Mount Step Box 18 Inch

    Smooth Aluminum Wide Big Mount Step Box 18 Inch

    ICONIC

    $729.99
    18 X 24 X 29.13 Inch Aluminum Big Mount Step Box* High Quality Big Mouth Step Box* Aluminum* Dimensions:  - 18.00 Inch Wide  - 24.00 Inch Height  - 29.13 Inch Depth* With Smooth Aluminum Lid * 50...
    09-020100537
    SKU:
    09-020100537
    Truck Class:
    Universal
    Width Options:
    18 Inch
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Smooth
    Product Type:
    Cargo Control
    Ready To Ship:
    Yes
    $729.99
    Qty in Cart: 0
    Price:
    $729.99
    Subtotal:
  • 22 Inch Smooth Aluminum Big Mouth Step Box W/ Lid

    22 Inch Smooth Aluminum Big Mouth Step Box W/ Lid

    ICONIC

    $759.99
    Big Mouth 22 X 24 Inch Smooth Aluminum Step Box* High Quality Step Box* Made Of Smooth Aluminum With Smooth Aluminum Lid* 22 Inch Wide* 24 Inch Height* 29.13 Inch Depth* Recommended 09-020100007...
    09-020100535
    SKU:
    09-020100535
    Truck Class:
    Universal
    Width Options:
    22 Inch
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Smooth
    Product Type:
    Cargo Control
    $759.99
    Qty in Cart: 0
    Price:
    $759.99
    Subtotal:
  • Diamond Plate Aluminum Step Saddle Box 36 x 25 x 28 Inch W/ Polished Side/Back Panels

    Diamond Plate Aluminum Step Saddle Box 36 x 25 x 28 Inch W/ Polished Side/Back Panels

    UNITED PACIFIC

    $902.99
    Aluminum Step Saddle Box W/ Locking Latch* High Quality Step Saddle Box* Made Of Aluminum* 36 Inch Length X 25 Inch Width X 28 Inch Height * Box Can Be Opened, Closed And Locked With Key* 2 Keys Are...
    09-020100534
    SKU:
    09-020100534
    Truck Class:
    Heavy Duty
    Make:
    Universal Items
    Material Options:
    Aluminum
    Finish Options:
    Diamond Plate
    Product Type:
    Cargo Control
    $902.99
    Qty in Cart: 0
    Price:
    $902.99
    Subtotal:
  • Diamond Plate Aluminum Step Saddle Box 18 x 25 x 28 Inch W/ Polished Back/Side Panels

    Diamond Plate Aluminum Step Saddle Box 18 x 25 x 28 Inch W/ Polished Back/Side Panels

    UNITED PACIFIC

    $618.99
    Aluminum Step Saddle Box With Lockable Door And Keys* High Quality Step Saddle Box * Made Of Aluminum* 18 Inch W X 25 Inch D X 28 Inch H * Box Can Be Opened* Closed And Locked With Key* 2 Keys Are...
    09-020100532
    SKU:
    09-020100532
    Truck Class:
    Heavy Duty
    Make:
    Universal Items
    Finish Options:
    Diamond Plate
    Material Options:
    Aluminum
    Product Type:
    Cargo Control
    $618.99
    Qty in Cart: 0
    Price:
    $618.99
    Subtotal:
  • Diamond Plate Aluminum Step Saddle Box 12 x 25 x 28 Inch W/ Polished Side/Back Panels

    Diamond Plate Aluminum Step Saddle Box 12 x 25 x 28 Inch W/ Polished Side/Back Panels

    UNITED PACIFIC

    $913.99
    Aluminum Step Saddle Box With Locking Door And 2 Keys* High Quality Step Saddle Box* 12 Inch L X 25 Inch W X 28 Inch * Aluminum Step* Box Can Be Opened, Closed And Locked With Key* 2 Keys Are...
    09-020100531
    SKU:
    09-020100531
    Truck Class:
    Heavy Duty
    Make:
    Universal Items
    Material Options:
    Aluminum
    Finish Options:
    Diamond Plate
    Product Type:
    Cargo Control
    $913.99
    Qty in Cart: 0
    Price:
    $913.99
    Subtotal:
  • Diamond Plate Aluminum Trailer Tongue Truck Box W/ Angled Front 18.5 X 15 X 49 Inch

    Diamond Plate Aluminum Trailer Tongue Truck Box W/ Angled Front 18.5 X 15 X 49 Inch

    BUYERS PRODUCTS

    $550.99
    18.5 X 15 X 49 Inch Diamond Plate Aluminum Trailer Tongue Truck Box W/ Angled FrontThis Diamond Tread Aluminum Trailer Tongue Truck Box is built tough to mount to A-frame style trailers. It keeps...
    09-020100518
    SKU:
    09-020100518
    Truck Class:
    Universal
    Make:
    Universal Items
    Material Options:
    Aluminum
    Product Type:
    Frame & Chassis
    $550.99
    Qty in Cart: 0
    Price:
    $550.99
    Subtotal:
  • Diamond Plate Aluminum Trailer Tongue Truck Box 15 X 14.5 X 34/22.5 Inch

    Diamond Plate Aluminum Trailer Tongue Truck Box 15 X 14.5 X 34/22.5 Inch

    BUYERS PRODUCTS

    $422.99
    15 X 14.5 X 34/22.5 Inch Diamond Plate Aluminum Trailer Tongue Truck BoxThis Diamond Tread Aluminum Trailer Tongue Truck Box is built for A-frame style trailers. It's tough yet lightweight with a...
    09-020100517
    SKU:
    09-020100517
    Truck Class:
    Universal
    Make:
    Universal Items
    Material Options:
    Aluminum
    Product Type:
    Frame & Chassis
    $422.99
    Qty in Cart: 0
    Price:
    $422.99
    Subtotal:
  • Black Steel Trailer Tongue Truck Tool Box 16.38 X 15 X 35.25/21.25 Inch

    Black Steel Trailer Tongue Truck Tool Box 16.38 X 15 X 35.25/21.25 Inch

    BUYERS PRODUCTS

    $411.99
    16.38 X 15 X 35.25/21.25 Inch Black Steel Trailer Tongue Truck Tool BoxAdd more storage to your A-Frame Trailer with this Black Steel Trailer Tongue Truck Tool Box. Its heavy-duty steel construction,...
    09-020100516
    SKU:
    09-020100516
    Truck Class:
    Universal
    Color:
    Black
    Width Options:
    35 Inch
    Material Options:
    Steel
    Make:
    Universal Items
    Product Type:
    Frame & Chassis
    $411.99
    Qty in Cart: 0
    Price:
    $411.99
    Subtotal:
  • Gloss Black Diamond Plate Aluminum Topside Truck Tool Box W/ Double Doors- 72 Inch

    Gloss Black Diamond Plate Aluminum Topside Truck Tool Box W/ Double Doors- 72 Inch

    AFTERMARKET

    $1,148.99
    72 Inch Gloss Black Diamond Plate Aluminum Topside Truck Tool Box W/ Double DoorsProtect your tools with the 72-Inch Gloss Black Diamond Plate Aluminum Topside Truck Tool Box with Double Doors...
    09-020100235
    SKU:
    09-020100235
    Color:
    Black
    Truck Class:
    Universal
    Height Options:
    17 Inch
    Width Options:
    13 Inch
    Length Options:
    72 Inch
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Diamond Plate
    Style Options:
    2 Door
    Product Type:
    Toolboxes
    $1,148.99
    Qty in Cart: 0
    Price:
    $1,148.99
    Subtotal:
  • Bright Diamond Plate Aluminum Topside Truck Tool Box W/ Double Doors- 72 Inch

    Bright Diamond Plate Aluminum Topside Truck Tool Box W/ Double Doors- 72 Inch

    AFTERMARKET

    $1,029.99
    72 Inch Bright Diamond Plate Aluminum Topside Truck Tool Box W/ Double DoorsKeep your tools organized and easily accessible with the 72 Inch Bright Diamond Plate Aluminum Topside Truck Tool Box with...
    09-020100234
    SKU:
    09-020100234
    Length Options:
    72 Inch
    Truck Class:
    Universal
    Height Options:
    17 Inch
    Width Options:
    13 Inch
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Diamond Plate
    Style Options:
    2 Door
    Product Type:
    Toolboxes
    $1,029.99
    Qty in Cart: 0
    Price:
    $1,029.99
    Subtotal:
  • Matte Black Diamond Plate Aluminum Deep Angled Crossover Tool Box- 69 Inch For Pickup Trucks

    Matte Black Diamond Plate Aluminum Deep Angled Crossover Tool Box- 69 Inch For Pickup Trucks

    AFTERMARKET

    $842.99
    69 Inch Matte Black Diamond Plate Aluminum Deep Angled Crossover Tool Box Fits Pickup TrucksProtect your tools and maximize truck bed space with the Matte Black Diamond Plate Aluminum Deep Angled...
    09-020100171
    SKU:
    09-020100171
    Width Options:
    20 Inch
    Length Options:
    69 Inch
    Color:
    Black
    Truck Class:
    Universal
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Diamond Plate
    Product Type:
    Toolboxes
    $842.99
    Qty in Cart: 0
    Price:
    $842.99
    Subtotal:
  • Bright Diamond Plate Aluminum Utility Chest Box- 48 Inch For Pickup Trucks

    Bright Diamond Plate Aluminum Utility Chest Box- 48 Inch For Pickup Trucks

    AFTERMARKET

    $648.99
    48 Inch Bright Diamond Plate Aluminum Utility Chest Box Fits Pickup TrucksKeep tools and equipment safe on the go with the 48-Inch Bright Diamond Plate Aluminum Utility Chest Box. Constructed from...
    09-020100060
    SKU:
    09-020100060
    Length Options:
    42 Inch
    Truck Class:
    Universal
    Width Options:
    24 Inch
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Diamond Plate
    Product Type:
    Toolboxes
    $648.99
    Qty in Cart: 0
    Price:
    $648.99
    Subtotal:
  • FREE SHIPPING OVER $249
    Battery Hold-Down Kit For 2 Group 30 Or Group 31 Batteries

    Battery Hold-Down Kit For 2 Group 30 Or Group 31 Batteries

    MINIMIZER

    $88.99
    Battery Hold Down Kit With Bolts, Nuts, Washer Plates, J Hookds, Flat Washers, Battery Clamps & Locking Nuts* High Quality Battery Hold Down Kit* Vent Holes Are Required When Storing Batteries In The...
    09-020100005
    SKU:
    09-020100005
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Frame & Chassis
    $88.99
    Qty in Cart: 0
    Price:
    $88.99
    Subtotal:
  • Minimizer Poly In-Frame Tool Box- 33.5 X 13.5 X 22 Inch

    Minimizer Poly In-Frame Tool Box- 33.5 X 13.5 X 22 Inch

    MINIMIZER

    $864.99
    33.5 X 13.5 X 22 Inch Poly Composite Between-Frame Tool Box By MinimizerEnsure dry, secure storage on your truck with the Minimizer Poly In-Frame Tool Box. Constructed from durable poly composite,...
    09-020100004
    SKU:
    09-020100004
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Toolboxes
    $864.99
    Qty in Cart: 0
    Price:
    $864.99
    Subtotal:
  • Limited Quantity Available
    Smooth Aluminum Fairing Tool Box 18 X 20 X 18 Inch With Top Chest Diamond Plate Lid

    Smooth Aluminum Fairing Tool Box 18 X 20 X 18 Inch With Top Chest Diamond Plate Lid

    ICONIC

    $589.99
    Aluminum Fairing Tool Box With Top Chest & Diamond Plate Aluminum Lid* High Quality Fairing Tool Box* With Top Chest Diamond Plate Aluminum Lid* Smooth Aluminum Body * Hasp Latch * Dimensions  - 18...
    09-020100003
    SKU:
    09-020100003
    Length Options:
    18 Inch
    Truck Class:
    Universal
    Width Options:
    18 Inch
    Material Options:
    Aluminum
    Make:
    Universal Items
    Finish Options:
    Smooth
    Product Type:
    Cargo Control
    $589.99
    Qty in Cart: 0
    Price:
    $589.99
    Subtotal:
  • BESTfit Air Spring Replaces 8864, 1R12-1097, 66666, AB1DK23L-8864 For Kenworth AG400L Suspension

    BESTfit Air Spring Replaces 8864, 1R12-1097, 66666, AB1DK23L-8864 For Kenworth AG400L Suspension

    BESTFIT TRUCK PARTS

    $193.99
    BESTfit Air Spring For Kenworth AG400L Suspension* High Quality Air Spring* Rolling Lobe Type* Plastic Base* Without Bumper* 5600 Lb Load At 80 PSI* 7100 Lb Load At 100 PSI* 65 CPM Natural Frequency*...
    02-051032K01
    SKU:
    02-051032K01
    Height Options:
    25 Inch
    Truck Class:
    Heavy Duty
    Rating:
    100 PSI
    Diameter Options:
    12 Inch
    Style Options:
    Rolling Lobe
    Material Options:
    Plastic/Poly
    Make:
    Kenworth
    Product Type:
    Frame & Chassis
    $193.99
    Qty in Cart: 0
    Price:
    $193.99
    Subtotal:
  • Bendix Idler Pin Replaces 238888BXW For Peterbilt 386

    Bendix Idler Pin Replaces 238888BXW For Peterbilt 386

    OPP - ORIGINAL PARTS PROGRAM

    $15.60
    Bendix Idler Pin Fits Peterbilt 386* High Quality Idler Pin * Sold Individually* Warranty On Idler Pin Against Defects In Workmanship & Material From Date Of Purchase*|** This Is An OEM Replacement...
    01-151700001
    SKU:
    01-151700001
    Location:
    Made In USA
    Truck Class:
    Heavy Duty
    Material Options:
    Steel
    Make:
    Peterbilt
    Product Type:
    Interior
    $15.60
    Qty in Cart: 0
    Price:
    $15.60
    Subtotal:
  • On Sale
    Limited Quantity Available
    Remote Lube Mount Bracket For Peterbilt 379, 386, 389

    Remote Lube Mount Bracket For Peterbilt 379, 386, 389

    IOWA CUSTOMS

    Now: $89.59
    Was: $127.99
    Peterbilt Remote Lube Mounting BracketSave time with this Heavy-Duty Lube Mount Bracket that relocates grease maintenance points to one location. Made from premium #8 304 Polished Stainless Steel, it...
    01-090500679
    SKU:
    01-090500679
    Truck Class:
    Heavy Duty
    Location:
    Made In USA
    Material Options:
    Stainless Steel
    Make:
    Peterbilt
    Product Type:
    Frame & Chassis
    Ready To Ship:
    Yes
    Now: $89.59
    Was: $127.99
    Qty in Cart: 0
    Price:
    Now: $89.59
    Was: $127.99
    Subtotal:
  • Luk Power Steering Pump Replaces 21D6751, LF73 For Peterbilt 379

    Luk Power Steering Pump Replaces 21D6751, LF73 For Peterbilt 379

    AFTERMARKET

    $401.99
    465.LUK.03 Power Steering Pump Fits Peterbilt 379The LUK Power Steering Pump replaces part numbers 21D6751 and LF73, specifically designed for Peterbilt 379 trucks. This high-quality power steering...
    01-0731000
    SKU:
    01-0731000
    Truck Class:
    Heavy Duty
    Make:
    Peterbilt
    Product Type:
    Engine Parts
    Material Options:
    Cast Iron
    $401.99
    Qty in Cart: 0
    Price:
    $401.99
    Subtotal:
  • Total: items /

Adding your products to cart

Discover Peterbilt 379 Rear Crossmember Designs

Reinforce your truck's structural support with Peterbilt 379 Frame Crossmembers & Covers. This lineup of aftermarket products includes high-quality fiberglass and stainless steel rear frame covers, fuel tank filler frames, rear frame covers, replacement cross members, and other essential components to keep your truck's frame in top condition. Handle the demands of commercial hauling with the best-in-class cross members featuring durable, stainless steel materials, corrosion-resistant finishes, and easy installation instructions. If you're looking for improved structural integrity for your frame, secure mounting points, and better load management, invest in quality frame cross members and covers to bolster your Peterbilt 379.

Frequently Asked Questions About Peterbilt 379 Frame Crossmembers & Covers

What are frame crossmembers and covers used for on a Peterbilt 379?

Frame crossmembers are structural components that run horizontally between the frame rails, providing rigidity and support to the chassis. Covers are typically used to shield these crossmembers or nearby frame sections from road debris, moisture, and corrosion while also giving the underside of the truck a cleaner, finished appearance.

Will these crossmembers and covers fit my specific Peterbilt 379 model year?

Peterbilt 379 frames can vary slightly depending on the model year and how the truck was originally configured, so it is important to check listed specifications such as frame rail width, mounting hole patterns, and wheelbase before purchasing. If you are unsure about fitment, reach out to our team with your VIN or frame measurements so we can help confirm compatibility.

What materials are these crossmembers and covers made from, and how do they hold up over time?

Most crossmembers and covers in this category are made from steel or aluminum, depending on the specific part and intended use. Steel components typically offer higher strength for structural applications, while aluminum covers are often chosen for reduced weight and natural corrosion resistance. Finish options may include raw metal, painted, or powder-coated surfaces to help protect against rust and wear from road exposure.

Are these parts a direct bolt-on replacement, or will modifications be needed for installation?

Many crossmembers and covers are designed to bolt into the existing mounting points on the frame, but installation can vary based on the part and whether your truck has had prior frame modifications. We recommend reviewing the product description for specific installation notes and having a qualified technician inspect your frame before installation, especially for structural crossmembers.

Do frame crossmembers affect the structural integrity or warranty of my truck?

Crossmembers play a role in the overall strength and stability of the frame, so it is important to select a part rated for your truck's application and to have it installed correctly. Improper installation or using a part not suited for your frame configuration can affect performance and safety. If your truck is still under any manufacturer or aftermarket warranty, check with the applicable warranty provider before making frame-related changes.


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