7 pole trailer connectors

[Egon]

Dielectric grease.

[newbury]

Timely thread -
I just rented a trailer to haul my new to me Kubota M4700 - Yesterday, in the rain, the trailer rental guy couldn't get the trailer running lights to stay on, (turn signals and brake lights worked) hooking up the tester to both the 4 prong & 7 prong (like Hopkins Multi-Tow 7-Way Blade and 4-Way Flat Trailer Connector - Toyota Hopkins Wiring HM43374) the tester would flicker when the trailer was on the ball. Took the trailer off the truck, the tester glowed solid. Couldn't rent the trailer without running lights in the rain.

Went back today, sunny, rented the trailer. Didn't ask about running lights.

Can my plug need replacing?

[Dallas_Lilly]

Thanks for the replies guys! I have a good cap and it is snug... It think what is happening is the actual contact on the truck or the trailer is not making contact because of corrosion. I am here in Arizona but at 7K feet elevation and for the last few years they have started using chemicals on the road, I do use dielectric grease on both ends but this stuff is horrible that they are using on the roads. That was the reason for the water proof junction boxes, but connectors and the like just dont cut it around here any more. Heat shrink works well also but if I have to replace the molded cable i then have to butcher everything again.

I like the idea of the military spec connectors, yes I would have to change all my trailers and it wouldn't be to industry standard but if someone needed to borrow one of my trailers I could make an adapter to go to a standard 7 pole flat..

I dont know though I could probably replace many more of the standard connectors for the price of the mil spec connectors...

[lostcause]

i've had my current truck for a little over 6 years, and i've never done any maintenance on the factory 7 way plug, and it's always worked. on prior vehicles where i had to install the plug myself i also never had issues. the only thing i've gone on my own installations is to make sure the wire is wrapped around the screw well, and then probably overtightened. after that i try to force a little extra of the wiring inside the plug / coupler before i tighten the strain relief screw. that just adds a little extra cushion if there is anything pulling on the wires, like massive chunks of ice. in the past i have also put a gob of silicone through and around the wires where it enters the truck side receptacle because in the winter months there is a large volume of crap spraying the underside of my vehicle. my truck is currently completely covered in a nice layer of dried road sand - about 1/16"-1/8" thick, and when i hooked up the trailer yesterday i had a nice clean socket. the only plugs i've ever had any problem with are the 4 way flat trailer plugs, which just don't fare too well up here.

[Dallas_Lilly]

I think I may have found what I need! This is pretty dang cool if you ask me... A little spendy though my frustration level may go down a bit....

http://ezconnector.com/

[5picker]

I think I may have found what I need! This is pretty dang cool if you ask me... A little spendy though my frustration level may go down a bit....

http://ezconnector.com/

No question that will help keep out the crud.
It's something though that's not 'standard' and like you said... if anyone borrows your trailers, they will need an adapter and/or if you tow someone else's trailer, you'll need the same.
If they would have added those sealing o-rings to a standard 7 pole flat connector it, would have served the same purpose and been compatible with industry standard... but maybe there are some copyright infringements or something?

We get a lot of crud here in the mountains of PA and I keep my plugs clean and use dielectric grease. Like I said, never a problem.
You might source an o-ring the proper size to slide on the outside of the plug and accomplish something similar.

Your idea of using a weatherproof junction box to replace the pigtail is good. Enclosed connections are always better than exposed butt connectors.

Personally, I don't care much for the molded connector/pigtail.
A lot of times when they manufacture those things they don't do a good job of attaching the wires to the connectors inside the plug.
I spent a lot of years as an automotive electrical technician and I've cut several of those types of connectors apart and a lot of times they just touch the wire to the connector tab and 'hope' the plastic which is molded around it, holds everything in place.
Unfortunately it doesn't... not for very long anyway.

If changing a plug I like to use something like this...

This way I know my connections are credible.

[r8nger]

Answere is simple, go to Fleetpride or any other heavy truck parts supplier and buy the plugs they use on tractor trailers. Buy the aluminum ones , not plastic, once you get everything changed over, they'll last a long time . 7 pin/ all round connectors, you can buy just the ends, then make an adapter for the odd occasion that you use someone else's trailer with the tv style flat blade plug

[Dallas_Lilly]

Answere is simple, go to Fleetpride or any other heavy truck parts supplier and buy the plugs they use on tractor trailers. Buy the aluminum ones , not plastic, once you get everything changed over, they'll last a long time . 7 pin/ all round connectors, you can buy just the ends, then make an adapter for the odd occasion that you use someone else's trailer with the tv style flat blade plug

That is a good idea. Flagstaff has 3 truck shops that could source those for me. They would have to be good if they service the tractor trailer industry...

[Dallas_Lilly]

I never thought about the connection inside the plug possibly giving me the problem, that very well could be and I am blaming the wrong part of the plug... I could solder the connections to the plug you have showed but what concerns me with those is keeping the crud out of the plug where the wires enter, that is not a weather proof connection unless you silicone it or something...

No question that will help keep out the crud.
It's something though that's not 'standard' and like you said... if anyone borrows your trailers, they will need an adapter and/or if you tow someone else's trailer, you'll need the same.
If they would have added those sealing o-rings to a standard 7 pole flat connector it, would have served the same purpose and been compatible with industry standard... but maybe there are some copyright infringements or something?

We get a lot of crud here in the mountains of PA and I keep my plugs clean and use dielectric grease. Like I said, never a problem.
You might source an o-ring the proper size to slide on the outside of the plug and accomplish something similar.

Your idea of using a weatherproof junction box to replace the pigtail is good. Enclosed connections are always better than exposed butt connectors.

Personally, I don't care much for the molded connector/pigtail.
A lot of times when they manufacture those things they don't do a good job of attaching the wires to the connectors inside the plug.
I spent a lot of years as an automotive electrical technician and I've cut several of those types of connectors apart and a lot of times they just touch the wire to the connector tab and 'hope' the plastic which is molded around it, holds everything in place.
Unfortunately it doesn't... not for very long anyway.

If changing a plug I like to use something like this...

This way I know my connections are credible.

[not2old]

I used to have problems but have eliminated them by going overboard on the installation of the female connection. I remove one of my license plate lights and grind out the hole to fit,so that the receptacle is located out of all the crud/spray that covers under the bumper. I then solder ring terminals to all wires before securing them to the screws. Any splices I make are all soldered and covered with heat shrink tubing before being well taped and then I pop rivet the connector to the bumper. Using this method, I've not had to repair anything on my truck. It is however, a big pain in the butt if I have to remove the bumper.