Trailer Ground Advice

[BoylermanCT]

I am replacing all the lights and wiring on my small 4x8 trailer. It has 4 pin wiring. I've hooked up everything except the ground wire. Is there a better way to connect the ground wire than drilling a hole and using a self tapping screw? Seems like I always have issues with the ground after a while, so I am wondering if there is a better way to connect the ground wire to the tongue. Once I connect the ground, if I am having trouble with the lights, I am guessing that there may be an issue with the grounding of that particular light. There is no ground wire going to each light. Would it help if I added one? If I add one, do they all need to be hooked into the one ground wire that goes into the harness, or can I simply use a 6" wire for each light, and drill a hole into the frame near the light and connect it there? I want to do this once, and not have to mess with it again for a while!

 

[Rustyiron]

I like to run a seperate (single) ground to all the lights, grounding that wire at each end, that is the last light you "hit", and up at the tongue. I don't think you have a ground with the flat 4 wire connector, if you do, ground it again there.
Grind the paint off of the frame and crimp on an "eye" at both of your grounds, then a 1/4" bolt/nut and dielectric grease to fight the corrosion devil. This helps finding out (and curing) the problem that is 9 out of 10 time, grounding issues with 2 locations rather than checking all the individual lights.

 

[cmyoung2]

I'm rewiring mine today also, but mine is a 7 pole plug. Your 4wire fall does have a ground wire, usually the white one, or the one that is bare on the vehicle side. I am running a ground wire to every light and to all the brakes. They may be also attached to the frame near the lights, but the wire will also go back to the harness to the truck. I am also using a junction box so the plug harness goes to the box, then all the other wires go from the box out to the lights/brakes. Makes splicing/replacing/trouble shooting a lot easier. I also gave up on light ga wire, using 14 for the lights, 10 or 12 for the brakes, and this is just a single axle 5x8'. (It does weigh about 1200 lbs empty, so it is not a light duty trailer, just not big)

 

[BoylermanCT]

Thanks for the replies. Yes, the 4 wire harness has a ground wire which is only about 18" long, designed to be attached to the tongue. I am hoping I don't need a ground to each light, but Murphy is telling me I will need it! If I need to extend the ground wire to go to all the lights, am I simply connecting the ground wire around one of the mounting bolts or screws that attaches the light fixture to the trailer The brake lights mount with 1/4" bolts to a bracket and the yellow side lights mount with 2 screws. I'll make sure I grind away any paint from the area and I'll pick up some dielectric grease too.

 

[amaxwell]

I would use a stainless screw or bolt, and stainless washer, when connecting the ground wire (wires) to prevent rust corrosion.

 

[weldingisfun]

If you have a good clean connection for the white lead you will be okay. The dielectric grease suggestion is a good one, as is the stainless steel screw.

 

[GLyford]

I also have a 4x8, and I not only ground the connector where the pigtail runs out, and at each light (usually with a mounting screw or bolt, as you say) but tied them all together with an added wire.

My previous truck used a converter box to go from separate turn signals to combined for the trailer. They seemed to only last a year before the salt? would kill them until I found one with double the amp rating, which did OK.

My current truck came with the 4-wire from the factory, but I found that the connector can still get flaky. I have to tweak it every so often so that it grips the trailer connector pins. The other thing I am doing that seams to be working is I use an 18" extension pigtail on the trailer. Any time the trailer connector gets messed up, I just unplug it and swap it out...beats replacing the whole harness.

 

[Soundguy]

if you use the lamps that ground to the frame, clean the paint off first!

hard to have too much ground.