Wiring '87 R truck for electric trailer brakes

[Keith Seymore]

Guys -

I've got an '87 Chevy "R" truck (...same as an '86 C/K) that I need to wire for electric trailer brakes.

Anybody know how to do that? I will be reusing my brake controller, which has seen a lot of use in newer (GMT800 and GMT900) style pickups, but have never done one this "vintage".

Need to wire for a 7 pin round ("Airstream") style receptacle.

Any advice would be appreciated.

Thanks -

K

[old Rusty C10]

cant help you with the wiring issue but i will say i love that malibu in the pic.... can i be so nosy to ask the story about it and for more pics??

[Keith Seymore]

Thanks for the comment; basically it's my first car, been in the family since new, and I still have it.

Rather than retyping the whole story here, if you don't mind I'll redirect you to a little biography I wrote here:

http://www.chevytalk.org/fusionbb/sh...hp?tid/199061/

The latest news is that we just finished up a photo shoot for Popular Hot Rodding yesterday, for publication in the near future.

Thanks again for the comment -

K

[TexasJeff]

http://www.easternmarine.com/em_stor...e_diagram.html


http://www.accessconnect.com/trailer_wiring_diagram.htm

I hope this helps, I just did it on my truck about a year ago.

[Keith Seymore]

Thanks, Jeff. I printed 'em off and will take a shot at it tomorrow.

K

[Gregs71]

Keith, I just finished putting a 7 way in my 87 3/4 ton silverado.

Pretty basic. My trailer brake controller had 4 wires. A positive and negative (per the instructions, both of mined attached the the + and - of the battery and I just used large round electrical wire connectors). The blue wire gets routed along the frame to the back of the truck and will control the electric brakes. The 4th wire went to the "cold wire" on the brake button under the dash. This means this wire only gets power when you apply the brake pedal. My 87 had a orange and white wire coming off the brake pedal button located above the brake pedal under the dash. On my truck the white wire was the "cold wire" and the one I connected the brake controller to.

If you need a constant 12v like I did, I just ran another wire from the battery along the frame to the back where the 7 way was.

I went to the auto parts store and purchased a 4 way trailer wire kit. I connected it to the taillights of my truck and then routed it to the 7 way plug. This allows you to get your turn signals and brake lights.

The 7th wire is usually an "auxillary" / extra wire which I did not use and just left open.

the colored wires do not correlate with the colors on the 7 way plug. Here is how I wired it(I used the horseshoe shaped connectors too):

Colored Wire--------Plug color identified
green wire to ----brown on plug
brown wire to-----green on plug
yellow wire to------red on plug
blue wire to --------blue on plug
white wire to -------ground
red wire (or 12v constant to---center of plug
auxillary wire (any color) to------black on plug

Be careful when running wires they won't hit/rub against any moving parts. When running wires thru the firewall, get a plug so the metal won't rub thru the wire or down the road you might be looking for a short. I also used wire loom along the frame (it was a pain but worth the piece of mind) so I would not have to worry about the wire eventually rubbing along the frame and shorting out.

Hope this advice helps. If you have any questions PM me.

Greg

[Keith Seymore]

Excellent post, Greg.

That's pretty much the conclusion I had come to. I've got some parts on order and once they arrive I'll take a shot at it.

I'll let you all know if I have any specific questions.

Thanks again -

K

[SCOTI]

Dusting an old one off......

Looking to integrate new trailer (truck/female side) & trailer (male side) connections on my 89 Dually. I didn't think it would be a big deal but after leaving NAPA & O'riellys today, I found no 'on the rack' adapters to make things simple.

Keith, any highlights you care to review after your install?

[mrolds88]

SCOTI, Here's what I have done. I use a Hoppy/Hopkins 41115 (or equivilent) and run those 4 wires into a 7 way. Then run a Blue wire for the brakes. That leaves 2 locations. 1 for reverse lights (which I don't have a trailer that has them........Yet. And 1 for auxiliary. Use that one to recharge the winch battery. I have also added a 4 flat that I tap into the terminals and run back out to haul my small trailer without having to use an adapter.

[SCOTI]

Originally Posted by mrolds88

SCOTI, Here's what I have done. I use a Hoppy/Hopkins 41115 (or equivilent) and run those 4 wires into a 7 way. Then run a Blue wire for the brakes. That leaves 2 locations. 1 for reverse lights (which I don't have a trailer that has them........Yet. And 1 for auxiliary. Use that one to recharge the winch battery. I have also added a 4 flat that I tap into the terminals and run back out to haul my small trailer without having to use an adapter.

Kind of what I had in mind vs keeping track of an adapter.

[Keith Seymore]

Originally Posted by SCOTI

Dusting an old one off......

Looking to integrate new trailer (truck/female side) & trailer (male side) connections on my 89 Dually. I didn't think it would be a big deal but after leaving NAPA & O'riellys today, I found no 'on the rack' adapters to make things simple.

Keith, any highlights you care to review after your install?

That was quite a while ago, but I remember it wasn't as bad as I thought it was going to be.

The posts above are very good (thanks again Greg and thanks Mrolds). I did go with a 7 pin round, which necessitates keeping track of an adapter, but I have to accomodate both a Haulmark enclosed with the big plug and my open trailer, which is a four pin flat connector.

K

[SCOTI]

Originally Posted by Keith Seymore

That was quite a while ago, but I remember it wasn't as bad as I thought it was going to be.

The posts above are very good (thanks again Greg and thanks Mrolds). I did go with a 7 pin round, which necessitates keeping track of an adapter, but I have to accomodate both a Haulmark enclosed with the big plug and my open trailer, which is a four pin flat connector.

K

I only haul my open trailer & it came w/a 4-pin flat connector.

But @ least 3 friends have borrowed it that have late model trucks w/the 7-pin set-up. I feel that since I have trailer brakes they should be functional for added safety & since I need to clean-up the junk wiring before putting my bed back on the frame, now is the time to use something more commom.

[83GMCK2500]

If it were me, I'd get one of the T kits for the vehicle, should be something like Curt 55312, firstly cutting of that flat 4 joke. (I picked 'burb to hopefully get into late squares) Then for the vehicle I'd put a Pollack/Hopkins HM40975-11998 (pictured) All you'd need is the brake controller, power for the trailer batt, reverse feed (optional). It may look familiar to anyone who owns a K2XX, it's the same connector that is on the back of the new trucks. It has both 7-flat RV, and 4-flat.

[SCOTI]

I think that's the one I have saved on my computer @ work. I'll check back tomorrow am. I held off today to research a little more.