M100 trailer harness length

[BCA]

Is anyone near their M100 trailer to measure then length of the heavy cable on the tongue of the trailer. It goes from the junction block tucked into the frame to the jeep receptacle. For simplicity the length I'd like to know is just the 3/4" thick portion of the cable between the rubber junction block to the jeep receptacle (just the cable; not including the rubber junction block or receptacle plug).

[Grant Hopkins]

I come up with 82 inches from neck to neck not including the plug or wiring block.

[BCA]

Hi Grant,
So far I have seen a wide variety on jeep trailers: with the cable (excluding the plug and the junction block) ranging from 44" to 61". Your 82" cable must excessively long and unwieldy? I think over the years a wide variety of cables were installed as the old ones deteriorated. I am still trying to determine the correct original length of the cable used on the M100.

[rob love]

Brian

I think the cable lengths changed due to application. With the M38A1, the trailer plug was way up on the top left, with the M151A2, it got a little closer, and with the Iltis it was only inches away. So many of the late releases were changed to a much shorter cable. I recall we would use whatever we had in stock that worked, whether it was for the M104, the M101, or the M100. I note that the original NSN was declared obsolete in 1993 and replaced with a much shorter one, just in time to be replaced by the Iltis trailer.

All that said, according to the parts CFTO, the Cdn trailer had a Cdn NSN of 2590-21-112-5311 and was 50 inches long.

I have an unmolested early release M100 at home which I can check tonight and see if it matches that description.

[BCA]

Hi Rob, the 2510-21-112-5311 (for the M101CDN "Iltis" trailer) is the shortest I have seen. The central cable, excluding plug and connector block, is 44". The overall length including pigtails is 58". I am curious is this short length is adequate for an M100 trailer hooked up to an M38 or M38A1. I don't have an M100 trailer handy to measure.

[peter simundson]

I have to install the two cables.

Trailer harness and front cable.

Peter S

[SteveJ]

Hi Brian

I have one of the early m100 trailer cables before they wired them directly to the junction box. Plug end to plug end this one is 72". So less each plug end gives 62 " of main cable. Hopes this helps

[rob love]

Iltis trailer used 01-376-8919. I'll have to check the length of those. I have both trailers at home. I know though that the Iltis one was a little too short.....a minor jack knife while towing with my M38A1 ripped the plug apart.

Distance from the center of the hitch to the M38A1 plug is only 26" btw.

[rob love]

I checked my M100, which is a early release trailer from the 70s, and it's cable was around 76" long.

I checked my M100CDN2 trailer, but remembered that I had changed the cable to a longer one that is about 65" long.

I had a look at the various cables in one of my parts bins, and found that the one cable that had no US p/n tag on it, and had the old metal shells, was 48" long. Very possible it is the 21-112-5311 cable.

As I mentioned, in service, we put whatever worked for length. We did not have judges looking at our work for originality, or customers complaining that it was a foot too long. We also liked stuff to go out and stay out, rather than come back a month later with the same problem again. If the 48" cable seemed too short, we would put on a cable from the 3/4 ton M101.

[mel gabel]

Brian, I measured the cable on my trailer, which I bought from you, and it is 48".

[BCA]

Mel: so far 48" seems to be the length of the cable on several M100 trailers although ranges between 44" and well above 48" have been observed. So far I haven't been able to locate a 48" cable that has a number tag intact. The length I refer to is the length of the thick central cable, not including the plug or the terminal block&pigtails.