null

Safety-Air-Electrical

Shop semi truck gladhands, air tanks, semi-trailer cords, 7-way receptacles and more. We stock premium aftermarket replacement air system and electrical components to maintain your truck’s critical air line connections.
  • Product
  • Qty in Cart
  • Quantity
  • Price
  • Subtotal
  • FREE SHIPPING OVER $249
    4 Ga. Battery Cable Lug With 5/16 Inch Stud

    4 Ga. Battery Cable Lug With 5/16 Inch Stud

    SPECTRO WIRE

    $3.05
    4 Gauge Battery Cable Terminal Lugs With 5/16 Inch Eye* High Quality Battery Lug* 4 Gauge* With 5/16 Eye* Sold Individually* Warranty On Battery Lugs Against Defects In Workmanship & Material From...
    09-16130103
    SKU:
    09-16130103
    Location:
    Made In USA
    Truck Class:
    Universal
    Size Options:
    4 Gauge
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    $3.05
    Qty in Cart: 0
    Price:
    $3.05
    Subtotal:
  • Battery Cable Lug, 4 Gauge #10 Mega

    Battery Cable Lug, 4 Gauge #10 Mega

    SPECTRO WIRE

    $3.11
    4 Gauge Battery Cable Terminal Lugs* High Quality Lug* 4 Gauge * 10 Mega Lug* Gray Die* Sold Individually* Warranty On Lugs Against Defects In Workmanship & Material From Date Of Purchase*** High...
    09-16130101
    SKU:
    09-16130101
    Truck Class:
    Universal
    Location:
    Made In USA
    Make:
    Universal Items
    Product Type:
    Lighting
    Ready To Ship:
    Yes
    $3.11
    Qty in Cart: 0
    Price:
    $3.11
    Subtotal:
  • FREE SHIPPING OVER $249
    5 Function LED Safety Flare W/ 12 Bright Red LED Lights, 5 Light Patterns,

    5 Function LED Safety Flare W/ 12 Bright Red LED Lights, 5 Light Patterns,

    AFTERMARKET

    $13.25
    Compact, Lightweight LED Safety Flare Uses 3 AAA Batteries* High Quality LED Safety Flare* 5 Functions Safety Devices Make Others Aware Of Your Vehicle Even If The Vehicle Battery Is Dead* Tough...
    09-160900004
    SKU:
    09-160900004
    Color:
    Red
    Truck Class:
    Universal
    Material Options:
    Plastic/Poly
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $13.25
    Qty in Cart: 0
    Price:
    $13.25
    Subtotal:
  • FREE SHIPPING OVER $249
    First Alert Battery-Operated Super Bright Red Flare Safety Device

    First Alert Battery-Operated Super Bright Red Flare Safety Device

    AFTERMARKET

    $18.96
    First Alert Flash Or Steady Super Bright LED Red FlareIf you are looking for a safe and reliable way to signal for help during roadside emergencies, the First Alert LED Roadside Emergency Beacon in...
    09-160900003
    SKU:
    09-160900003
    Color:
    Red
    Truck Class:
    Universal
    Style Options:
    Magnetic Mount
    Material Options:
    Plastic/Poly
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $18.96
    Qty in Cart: 0
    Price:
    $18.96
    Subtotal:
  • High Beam Relay Kit

    High Beam Relay Kit

    AFTERMARKET

    $63.99
    High Beam Relay Kit* High Quality High Beam Relay Kit* Sold Individually* Warranty On High Beam Relay Kit Against Defects In Workmanship & Material From Date Of Purchase***High Quality Aftermarket...
    09-1606089
    SKU:
    09-1606089
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    $63.99
    Qty in Cart: 0
    Price:
    $63.99
    Subtotal:
  • FREE SHIPPING OVER $249
    11 Inch Black Plastic Ties - 100 Pack

    11 Inch Black Plastic Ties - 100 Pack

    OPP - ORIGINAL PARTS PROGRAM

    $12.59
    Black Plastic TiesSecure and organize your stuff effortlessly with these 11-inch black plastic ties. Perfect for tidying up cables, gardening, or DIY projects, this 100 pack ensures you'll have...
    09-16040253
    SKU:
    09-16040253
    Length Options:
    11 Inch
    Truck Class:
    Universal
    Color:
    Black
    Material Options:
    Plastic/Poly
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $12.59
    Qty in Cart: 0
    Price:
    $12.59
    Subtotal:
  • On Sale
    FREE SHIPPING OVER $249
    Limited Quantity Available
    Jacketed 7 Way Wire Trailer Cable 6/14 & 1/12 Gauge - Sold Per Foot

    Jacketed 7 Way Wire Trailer Cable 6/14 & 1/12 Gauge - Sold Per Foot

    TRAMEC SLOAN

    Now: $3.94
    Was: $5.63
    14 Gauge 6 Conductor + 12 Gauge 1 Conductor Trailer Cable Wire - Sold Per FootDo you need 7-way wire? 4 State Trucks carries PVC-jacketed 7-Way wire trailer cable which is sold per foot . This wire...
    09-16039901
    SKU:
    09-16039901
    Truck Class:
    Universal
    Material Options:
    Plastic/Poly
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    Now: $3.94
    Was: $5.63
    Qty in Cart: 0
    Price:
    Now: $3.94
    Was: $5.63
    Subtotal:
  • FREE SHIPPING OVER $249
    4 Way Pvc Wire Trailer Cable

    4 Way Pvc Wire Trailer Cable

    PARTS DISTRIBUTING

    $4.36
    4/14 Trailer Cable Sold By Foot* High Quality Wire* 4 Way Wire* Sold Per Foot* Jacketed With Tough, Durable PVC* Remains Flexible Down To -85 Degrees Fahrenheit* Inner Conductors Are Paper Wrapped*...
    09-16039900
    SKU:
    09-16039900
    Truck Class:
    Universal
    Material Options:
    Plastic/Poly
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    $4.36
    Qty in Cart: 0
    Price:
    $4.36
    Subtotal:
  • FREE SHIPPING OVER $249
    14 Gauge White Wire 1000 Foot

    14 Gauge White Wire 1000 Foot

    PARTS DISTRIBUTING

    $163.99
    14 Gauge White Wire 1000 Foot* High Quality Wire* 14 Gauge* White * 1000 Foot Roll* Sold Individually* Warranty On Wire Against Defects In Workmanship & Material From Date Of Purchase***High Quality...
    09-16031409
    SKU:
    09-16031409
    Truck Class:
    Universal
    Color:
    White
    Size Options:
    14 Gauge
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $163.99
    Qty in Cart: 0
    Price:
    $163.99
    Subtotal:
  • FREE SHIPPING OVER $249
    14 Gauge Black Electrical Wire - Sold By Foot - 1000 Foot Roll

    14 Gauge Black Electrical Wire - Sold By Foot - 1000 Foot Roll

    PARTS DISTRIBUTING

    $2.03
    14 Gauge Black Electrical WireDo you have a wire project your are working on? 4 State Trucks stocks plenty of wiring options including this black 14 gauge wire. Great for big or small jobs. Our wire...
    09-16031406
    SKU:
    09-16031406
    Truck Class:
    Universal
    Color:
    Black
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    $2.03
    Qty in Cart: 0
    Price:
    $2.03
    Subtotal:
  • FREE SHIPPING OVER $249
    4 Gauge Red Battery Cable Sold Per Foot

    4 Gauge Red Battery Cable Sold Per Foot

    TRAMEC SLOAN

    $4.27
    Red 4 Gauge Battery CableIn the market for red battery cable? 4 State Trucks sells red 4 gauge battery cable by the foot to make sure you have the correct amount for your next project.* High Quality...
    09-16030407
    SKU:
    09-16030407
    Color:
    Red
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    $4.27
    Qty in Cart: 0
    Price:
    $4.27
    Subtotal:
  • FREE SHIPPING OVER $249
    Black 4 Gauge Battery Cable

    Black 4 Gauge Battery Cable

    TRAMEC SLOAN

    $3.05
    4 Gauge Black Battery CableDo you need battery cable? 4 State Trucks offers black 4 gauge battery cable sold by the foot to tackle any project you may have.* High Quality Battery Cable* 4 Gauge...
    09-16030406
    SKU:
    09-16030406
    Color:
    Black
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    Ready To Ship:
    Yes
    $3.05
    Qty in Cart: 0
    Price:
    $3.05
    Subtotal:
  • Circuit Breaker Auto Reset 80A

    Circuit Breaker Auto Reset 80A

    AUTOMANN USA

    $39.57
    Circuit Breaker Auto Reset 80A W/ Interrupt Rating 3000 Amps At 30V DCSafeguard your truck's circuits with the 80A Auto Reset Circuit Breaker, engineered for heavy-duty performance. With a 30V DC...
    09-16030322
    SKU:
    09-16030322
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $39.57
    Qty in Cart: 0
    Price:
    $39.57
    Subtotal:
  • Circuit Breaker Auto Reset 60A

    Circuit Breaker Auto Reset 60A

    AUTOMANN USA

    $39.57
    Circuit Breaker Auto Reset 60A W/ Interrupt Rating 3000 Amps At 30V DC* High Quality Circuit Breaker* Auto Reset 60A* Waterproof* Rating 30V DC Maximum* Interrupt Rating 3000 Amps At 30V DC*...
    09-16030321
    SKU:
    09-16030321
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $39.57
    Qty in Cart: 0
    Price:
    $39.57
    Subtotal:
  • Circuit Breaker Auto Reset 50A

    Circuit Breaker Auto Reset 50A

    AUTOMANN USA

    $39.57
    Circuit Breaker Auto Reset 50A W/ Interrupt Rating 3000 Amps At 30V DC* High Quality Circuit Breaker* Auto Reset 50A* Waterproof* Rating 30V DC Maximum* Interrupt Rating 3000 Amps At 30V DC*...
    09-16030320
    SKU:
    09-16030320
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $39.57
    Qty in Cart: 0
    Price:
    $39.57
    Subtotal:
  • Circuit Breaker Auto Reset 150A

    Circuit Breaker Auto Reset 150A

    AUTOMANN USA

    $39.57
    Circuit Breaker Auto Reset 150A W/ Rating 30V DC Maximum* High Quality Circuit Breaker* Auto Reset 150A* Waterproof* Rating 30V DC Maximum* Interrupt Rating 3000 Amps At 30V DC* Operating Temperature...
    09-16030319
    SKU:
    09-16030319
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $39.57
    Qty in Cart: 0
    Price:
    $39.57
    Subtotal:
  • Circuit Breaker Auto Reset 120A

    Circuit Breaker Auto Reset 120A

    AUTOMANN USA

    $39.57
    Circuit Breaker Auto Reset 120A W/ Rating 30V DC Maximum* High Quality Circuit Breaker* Auto Reset 120A* Waterproof* Rating 30V DC Maximum* Interrupt Rating 3000 Amps At 30V DC* Operating Temperature...
    09-16030318
    SKU:
    09-16030318
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $39.57
    Qty in Cart: 0
    Price:
    $39.57
    Subtotal:
  • Circuit Breaker ATC Blade 100A

    Circuit Breaker ATC Blade 100A

    AUTOMANN USA

    $39.57
    Circuit Breaker ATC Blade 100A W/ Rating 30V DC Maximum* High Quality Circuit Breaker* Auto Reset 100A* Waterproof* Rating 30V DC Maximum* Interrupt Rating 3000 Amps At 30V DC* Operating Temperature...
    09-16030317
    SKU:
    09-16030317
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $39.57
    Qty in Cart: 0
    Price:
    $39.57
    Subtotal:
  • Circuit Breaker ATC Blade 30A

    Circuit Breaker ATC Blade 30A

    AUTOMANN USA

    $6.21
    Auto Reset Circuit Breaker ATC Blade 30AProtect essential electrical circuits on your truck with the 30A ATC Blade Circuit Breaker. Engineered to meet SAE J553 standards, it handles 14V DC systems...
    09-16030316
    SKU:
    09-16030316
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $6.21
    Qty in Cart: 0
    Price:
    $6.21
    Subtotal:
  • Circuit Breaker ATC Blade 25A

    Circuit Breaker ATC Blade 25A

    AUTOMANN USA

    $7.61
    Auto Reset Circuit Breaker ATC Blade 25AMaintain peak electrical safety with the Circuit Breaker ATC Blade 25A. Built to SAE J553 specifications, this 25-amp breaker supports 14V DC maximum and...
    09-16030315
    SKU:
    09-16030315
    Truck Class:
    Universal
    Make:
    Universal Items
    Product Type:
    Air, Electrical, & Safety
    $7.61
    Qty in Cart: 0
    Price:
    $7.61
    Subtotal:
  • Total: items /

Adding your products to cart

Semi Truck Gladhands & Air Connections

A semi truck gladhand is the critical connection point between your tractor air lines and the trailer’s air-brake system. These heavy-duty couplers lock together with a rubber seal to hold air pressure securely. Our inventory helps you restore and replace your existing gladhand configuration when it’s cracked, leaking, corroded, or damaged. Semi Truck Gladhand Replacements: Replace worn or damaged tractor-trailer air couplers to restore a tight, reliable air connection. Service Gladhands: Blue service gladhands carry control air used to apply the trailer brakes during normal braking. Emergency Gladhands: Red emergency gladhands supply constant air pressure to the trailer and keep the emergency spring brakes released while driving. Gladhand Seals and Replacement Parts: Replace cracked, flattened, hardened, or leaking seals when the gladhand body and locking tabs remain in good condition. Air Lines with Gladhands: Find 2-in-1, 3-in-1, ABS, and power air lines to replace chafed, cracked, stretched, or worn tractor-trailer connections.

Signs of a Leaking Gladhand

Replace or inspect the gladhand when you notice hissing, air-pressure loss, frequent compressor cycling, slow air recovery, visible seal damage, or air leaking at the tractor-trailer connection.

Gladhand Seals vs. Complete Couplers

Replace the rubber seal when the coupler body is solid but the gasket is worn, cracked, flattened, or leaking. Replace the complete gladhand when the body, locking tabs, threads, or sealing surface is damaged or badly corroded.

Individual Gladhands vs. Complete Air-Line Assemblies

Individual gladhands make sense when your hoses remain in good condition and only the coupler needs replacement. Complete air-line assemblies replace the hoses and connections together. Choose them when lines are cracked, weathered, stretched, damaged, or due for replacement.

Air Brake Valves & Controls

We stock tractor-trailer air-brake protection valves, quick-release valves, emergency relay valves, and MV3 dash valves. Replace worn PP5 and PPDC control valves, trailer brake valves, and related spring brake components to restore proper air-brake control.

Air System Maintenance & Repair Parts

Maintain and repair your air system with air dryers, air solenoid valves, air hoses, fittings, and air tank hardware. Emergency air-brake and in-cab air-line repair kits also help address damaged lines and fittings during roadside repairs.

Trailer ABS & Electrical Connections

Keep tractor-trailer air and electrical connections organized with ABS cables, 7-way electrical cords, wrapped hose assemblies, air-line boxes, and pogo sticks. Replace worn or damaged connection hardware to protect air lines, power cords, and ABS wiring from dragging, chafing, and road damage.

Frequently Asked Questions About Semi-Truck Safety, Air & Electrical

What air pressure switches and valves are compatible with my specific truck model?

Compatibility depends on your truck's make, model, and year. Most Freightliner Cascadia models (2008-2023) use standard 1/4" NPT air pressure switches rated at 90-120 PSI. Peterbilt 579/389 models typically require 1/8" NPT connections. Kenworth T680/W900 models often use proprietary valve configurations. Always check your truck's service manual for exact specifications, or contact our technical support team with your OEM for precise matching.

How difficult is it to install safety lighting and electrical components myself?

Installation difficulty varies by component. LED marker lights and basic warning lights typically require 30-60 minutes with basic tools and can be DIY-installed by following color-coded wiring (white=ground, black=power). Air horns and pressure gauges require air line connections and may need professional installation to avoid leaks. Complex items like backup cameras or multi-circuit lighting systems often require 2-4 hours and intermediate electrical knowledge. We provide detailed installation guides with each product, and most customers report successful DIY installation for basic components.

What's the actual lifespan of LED safety lights versus traditional bulbs in real-world conditions?

Based on customer feedback and warranty data, quality LED safety lights last 30,000-50,000 hours of operation, which translates to 5-8 years of typical commercial use. Traditional incandescent bulbs average 1,000-2,000 hours (6-12 months). LEDs handle vibration better and maintain brightness longer. However, cheaper LED units may fail within 1-2 years due to poor heat dissipation or inadequate weatherproofing. We recommend DOT-certified LEDs with aluminum housings and IP67 or higher waterproof ratings for maximum longevity.

Which air brake components fail most frequently and what are the warning signs?

The most common failures occur in air dryers (every 2-3 years), pressure protection valves (3-4 years), and gladhand seals (annually). Warning signs include: air dryer constantly purging or not purging at all, slow air pressure build-up taking over 3 minutes to reach 90 PSI, air leaks audible when brakes are released, and moisture in air tanks. Quick-release valves often stick in winter conditions. Regular maintenance with quality replacement parts can extend component life by 30-50%.

What gauge and type of wiring should I use for adding auxiliary lights and accessories?

Wire gauge depends on the accessory's amperage draw and cable run length. For LED marker lights (0.5-2 amps), use 18-16 AWG wire for runs under 15 feet. Work lights and fog lights (3-10 amps) require 14-12 AWG wire. High-powered LED light bars (15-30 amps) need 10 AWG wire with inline fuses. Always use automotive-grade stranded copper wire with SAE J1128 rating for flexibility and heat resistance. Install proper fuses or circuit breakers rated at 125% of the accessory's amp draw. Avoid household solid-core wire as it becomes brittle and cracks from vibration.


Introducing the Official 4 State Trucks Mobile App – Gear Up On the Go!