Trailer Wiring adapter for CUCV...

[hooyahdiver]

I bought a trailer wiring adapter for an 86 Chevy truck. Obviously it doesn't fit. The connector is a 4 pin square one when I actually need a 3 pin flat one. I read an article on this web site that says an 83 adapter will fit. Can anyone confirm this is true? The CarQuest I use is locally owned. I'll feel like a jerk if I get him to order another one and it's not right. Thanks ahead.

 

[4bogginchevys]

If you are trying to get the "T" connector to run a "FLAT 4" (3 pins + GRD) the autozone p/n is 74425 for a reese, and 41105 for hopkins (1983). Yes the 86 (wrong) has a different p/n than the 83, the parts listed will work back to atleast 78' and your local auto parts store should be able to cross the #'s for you.

 

[CUCV85]

Trailer Wire Harness - Tow Vehicle -
Product Line: Balkamp
Part Number: BK 7551554
Price 16.09
Features & Benefits Does Not Need Any Stripping or Slicing of Wires, Adapter Just Plugs in For Easy, Accurate Fit Warranty 1 Year Attributes # of Wires from Adapter to Connector : 4
Direct Fit or Universal : Direct Fit
Manufacturer : Hopkins Manufacturing Company
Manufacturer Part Number : 1170311005
Material Safety Data Sheet There is no MSDS for this item Application Information: 1984 Chevrolet Truck

 

[hooyahdiver]

If you are trying to get the "T" connector to run a "FLAT 4" (3 pins + GRD) the autozone p/n is 74425 for a reese, and 41105 for hopkins (1983). Yes the 86 (wrong) has a different p/n than the 83, the parts listed will work back to atleast 78' and your local auto parts store should be able to cross the #'s for you.

There are 2 places where the "T" connector can plug in, one at each end of the back of the truck below the taillight assy. Each has 3 male spade connectors coming from the harness with 4 female spade connections coming from the taillight. Is it sufficient to put the "T" connector in between one of these connections or will I have to run a turn signal line from the other taillight assy? The reason I'm asking is that I think it's unlikely if there are only 3 wires in the bundle for each taillight, that 2 of them are separate turn signal lights. It's kind of moot because I've already ordered the part and I'll find out for myself tomorrow.

Thanks for the part numbers and the info.

 

[4bogginchevys]

brake is turn......plug in on drivers side or you wont have a left blinker

 

[Midnight Rider]

I bought the one that fits Pre-84 model Chevys from Napa. Works fine, but I think I need to upgrade to the heavy duty flasher. At least I thought I read that somewhere on here before. It seemed to work like it is, but my blinkers were going twice as fast when I had the trailer on there.

 

[hooyahdiver]

brake is turn......plug in on drivers side or you wont have a left blinker

Did you mean plug in on the right side (passenger) or I won't have a left blinker? I put in on the driver's side and, as I suspected, only the functions of the left light work. I'll plug it in on the right side tomorrow. Maybe the problem is that I disconnected the NATO trailer connector. I really don't want to splice any wires. Ahh...

 

[lavarok]

For civilian trailer connectors, I just use the blue trailer splice connectors. There are two wiring harnesses that connect to the military trailer plug. On the vehicle side harness, behind the bumper is where I connect. One harness has the black, yellow, and brown/white. The other has green, brown, and green/white.

Connect:
green to green
brown to brown
yellow to yellow
white to black ( ground )

 

[jimm1009]

Any older truck or car of that era needs a heavy duty flasher when you hook up a trailer. The standard flasher is only strong enough for four bulbs which is the four on the tow vehicle. left and right front / left and right rear.
#5 & 6 from the trailer make it malfunction.
Heavy duty is what you need and no problems from there on.

You can also buy the MS grade plug and use the military OEM connector and connect the civilian four pin flat connector to it. I did and I wired in a four pin male and a four pin female because some people install the wrong half on their trailers when they rewire them or repair them dosn the road.

jimm1009

 

[4bogginchevys]

if the military plug is diconnected than that sounds like a problem. In this instance it should be no different than my 79 gmc....the wires for all operations run along the frame rail (drivers side) to the rear, then they "split" to thier respective side...at this junction is where you plug in tour T. Again, that wiring that is disconnected has to be the problem based on what info you have provided. Good Luck

 

[lavarok]

if the military plug is diconnected than that sounds like a problem. In this instance it should be no different than my 79 gmc....the wires for all operations run along the frame rail (drivers side) to the rear, then they "split" to thier respective side...at this junction is where you plug in tour T. Again, that wiring that is disconnected has to be the problem based on what info you have provided. Good Luck

Per the TM wiring diagrams, the military plug is spliced from the other circuits. If the two harnesses are disconnected from the military plug it should not affect light operation or the addition of a "T".

 

[hooyahdiver]

I plugged the NATO trailer connector back in. Still no joy. The harness may be defective. This is annoying.

 

[ida34]

The vehicle harness for all the trucks were the same as the year of procurement. They did not get the updated connectors because they are not what was accepted by the government and they did not want to stock different parts based on the year by year changes. Get everything for these trucks by stating they are a 1984 no matter what year they are. I do not know why, but I had to run a jumper for the right turn signal with my harness. I never found out why. My truck is a M1009. Plug the connector in on the driver's side and just run a jumper and tap from the right turn signal. Having the military trailer connector will not have any effect on the other wiring. I hope this helps.

 

[jatonka]

If you all notice I've been thanking people with useful info on CUCVs. My realm is deuces, but I bought a pair of 1008s and I am really starting to like them. one has a plow on it and its great. better than the skidsteer without cab I must admit. JT out

 

[hooyahdiver]

Postscript...

I finally got time to wire up these stupid trailer lights today. On my wiring harness there are 3 spade connectors coming of the trucks harness at each taillight assy. One is the respective turn signal. One is the running light. And the other is probably a ground or the reverse. Don't know for sure except that it is most assuredly NOT the turn signal for the opposite lamp. To shorten the story, I had to run a wire from the "T" connector to the opposite taillight defeating the whole purpose of the "T" connector. Anyway, it's all together and working. Thanks for the help.

 

[hooyahdiver]

How did your trailer wiring turn out on the 1028? I'm looking to do the same shortly and wondered if the plug-and-play T connector will work. From the thread it sounds like it will but I wanted to know how you resolved yours. Thanks, Sam.

---I’m happy with the result but I spent a lot of money unnecessarily and I did a lot of unnecessary work. I don’t recommend that adapter for the simple fact that you’ll have to run a wire to the passenger light anyway so you may as well buy a universal harness. My intention was to avoid splicing into wires but the national guard guys had already spliced into them and, like I said, there is no way around splicing a wire to the right turn signal unless you bought X2 T connectors for both sides and did some engineering. That’s retarded. Anyway, that T-connector they sell is for a flat 4 pin and my trailer is a 7 pin with brakes so I spent a good amount of time trying to get that “T” connector to work (because it was had a layer of rubber between the contacts and I didn't notice and couldn't figure out why it wouldn't work) then running the extra wires for the 7 pin. In hindsight, I’d have bought a universal 7 pin connector with the flat 4 pin built in. I ran 3 extra wires: 1 for the brake controller and 1 for the aux pwr and there’s constant 12v from the front batt to the brake controller with a toggle switch cut off.

I put the 7 pin connector where the military trailer connector used to be. I had to get an angle grinder to open the hole by ¼ in or so. If I had it to do over I’d have used a 2 ¼ hole saw and made another hole below the military connector or just mounted it underneath the bumper. If you mount it in the bumper where the original trailer connector hole, you’ll have to either remove or modify the pindle hook braces. I took mine off.

Let me know if you want to know about the hitch install. It was a much bigger pain in the butt than the wiring harness.

 

[markinnh]

Hope you guys get it all figured out. I would just like to use the military receptacle. I think the switched blackout tail light coud be hooked up as nice low wattage "night loading"lights. Can anyone help me find the correct plug or part number for the plug and pigtail or just the plug connector body?

Much thanks in advance

 

[niferous]

I just re-did all the lights on my M101A2 trailer with the civi style lights. I did so because I wanted to be able to lend the trailer to friends and not have to worry about them trying to wire in some temporary lights. Anyhow I went ahead and left all my military trailer lights on my M1009 but I also went ahead and got one of those quick plugs that has been talked about earlier from NAPA. I plugged it into the driver's side and all the running lights work, the driver's side turn signal and brake light. Nothing else does though!

So how are you guys wiring that jumper? Just a wire from the passenger side and into the wire over on the trailer plug? I'm tempted to take the thing back as much as it cost me ($16). Just use a universal mount.

 

[tankie88]

Fixed the blinker relay prob,no prob.Get a 3 pin 12v blinker relay,make 3 bridging wires,connect terminal 49 to power (l/h connection on fuse block relay socket),terminal 31 to earth/ground on body,49a to blinker switch(top connection on fuse block relay socket).....job done.Trailer blinks at the same rate as the chevy.Oh and cable tie/zip tie the relay up out the way.Oh and i have 2 trailer sockets ...the normal US Nato socket and on the left of the tow hitch a 7 pin civi socket.The nato plug on my trailer i cut off as the Brit trailer would not work properly on the US nato socket.The trailer now has a civi 7 pin plug.

 

[jmassenga]

Or you can buy a cheap flat 4, and a complete 3-pin weatherpack connector (1 male end, 1 female end) and build your own adapter that will plug in right where the military trailer plug connects to the wiring harness. You can switch between military and civilian wiring in about 30 seconds.