GXL vs. TXL vs. SXL: What's the difference?

Choosing the wrong automotive wire can create significant performance issues and even lead to overheating or ignition in certain conditions. With a broad list of options to consider, selecting the appropriate wire can be daunting. Here we break down the subtle differences between three types of single-conductor primary wire with XLPE insulation: GXL, TXL and SXL. Generally speaking, it's the insulation thickness that differentiates these wires:

SXL = Standard

The thickest insulation of the three, SXL is good for high-temp spaces like engine compartments where space is less of a concern

GXL = Thin

This is generally used in high temp spaces where flexibility and reliability are needed. While it is thin walled, there is a thinner option.

TXL = Extra Thin

TXL is the thinnest option, making it ideal when space is at a premium. Extra thin wall also makes it lighter than the others.

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Primary Wire Solutions

IEWC is one of the world’s leading providers of automotive primary wire. Our standard offering is always in stock and meets SAE J-1128, Ford, and Chrysler specifications. However there are many variations of primary wire for the world’s automotive applications. Review your conductor and stranding options and also consider the termination and flexibility needs of your application.


  • Anti-capillary constructions to help prevent moisture collection
  • High-strand versions for additional flexibility
  • UL-rated cable for RV and other applications
  • Top-coated conductors to ease termination

Services offered:

  • Drum box and drum packing options to match inventory to your production capabilities
  • Wire striping to ensure quick identification in a harness
  • Dyeing services for color-conscious applications

IEWC maintains one of the largest stocks of ISO automotive wire, as well as for marine applications. Browse our primary wire here, or contact your IEWC sales rep to discuss how we can deliver wire and cable attuned to your production needs.

Primary Wire Management

Organize, bundle and protect wire harnesses with Flexo® PET or the self-wrapping F6®. Terminate your applications with Shrinkflex® Fabric heatshrink tubing while adding abrasion protection as well as moisture and heat resistance.