• To ALL forum users - As of late I have been getting quite a few private messages with questions about build ups here on the forum, or tech questions about your personal project. While I appreciate the interest, sending me a private message about these topics distracts from, and undermines the purpose of having a forum here. During the day I wear many hats as a small business owner-operator and I work tirelessly to provide the absolute best service possible to you, our valued customer. When I created this forum I rounded up some of the best minds I knew so that any tech question you might have could be asked and answered by either myself or one of my highly experienced moderators, this way the next time this same question is asked the answer can be easily found and utilized by the next IH enthusiast having the same question. This allows me the freedom to run the day to day operations of the business and minimize the impact to shipments and shop activities that these distractions can cause. It is of the up most importance for me to complete the daily tasks in order to best take care of you our customer, all the while providing you a forum to get the level advice and input you have come to expect and deserve from the premier IH shop in the country.

    So with that I ask that anyone with a question about one of our build ups or a general tech question to please use the forum as it was intended. I am absolutely available by telephone to answer your questions as well but at times may direct you back to our website to better field your question or questions. Most other private messages I will be glad to answer for you.

    Thank you for your understanding.

    Jeff Ismail

Auto Wire Info


I know a lot of people choose a full wire kit to replace their wires all at once. And perhaps I’d come out cheaper in the end if I just went ahead and did that. But I have just been replacing sections of wire as I need to due to corrosion, bad connections, heat damage, etc. In any case, I thought this information might be helpful to others that May only replace sections of wire.

sae j1128 gpt is a pvc insulated wire rated at 194f used for general chassis wiring, and should not be used in the engine compartment of your car according to the sae j1128 spec. It's not as tough or heat resistant as txl or gxl insulation, but it is considerably cheaper. This is the wire found in retail stores.

txl is the wire used by vehicle manufacturers for most applications, and is the thinnest, lightest, and lowest cost of these insulations. It is tough and long lasting.

gxl is an intermediate insulation, with thickness and cost between txl and sxl. Medium thick insulation, 257f, 18-12 ga wire.

sxl is the second thickest of the crosslinked polyethylene insulations, and suggested for use in the heavier gauges, or where some additional protection from possible mechanical damage is needed. Heavy thick insulation, 257f, 8-10 ga wire.

sgx is the thickest of the crosslinked polyethylene insulations. Sgx is particularly recommended for battery cable, because of the rather spectacular consequences of a shorted battery cable. Heavy thick insulation, 257f, 6-0 ga wire.

when in doubt, use 257f rated txl, gxl, sxl, or sgx wire insulation for engine compartment and general wiring. The only difference between these is the thickness of the insulation and cost, with the thicker being the more expensive. They are all insulated with crosslinked polyethylene, which is almost as heat resistant as teflon, but cheaper and much tougher.

cost relation from del city
16ga, gpt, 100’, $10.61
16ga, gxl, 100’, $12.75
16ga, sxl, 100’, $15.71


Greg R

Good info x2!

As I sometimes rewire machinery in my day job, I've often thought about wire specs for vehicles; but I never pursued it like you did. Many times I've questioned whether the wire I buy for rigs is quality or not. Now I know what to look for.