Time to update/upgrade the GMC '99 Suburban 2500 receiver hitch & wiring

[truxpin]

The closer we get to finding our "perfect" Airstream trailer, the more I start finetuning the TV.
Todays project is removing the OEM receiver hitch & previous owners wiring and starting over with all new goodies!
I started off ordering a new Curt class IV receiver p/n 14029 , rated for 10K GTW & 1K tounge (12.5K & 1.5K w/ weight dist.) , a new Tekonsha Primus IQ Electronic Brake Control, p/n 90160, new Curt round 7 blade RV connector, and a "T-Connector" wiring adapter. ( which looks like I may not have needed!)
I must include in here that I bought these on-line through

Largo, FL Trailer Hitch - 5th Wheel Hitch - Trailer Parts

Great website, easy ordering & 1 day later I had my new brake controller, and the day after that everything else! All delivered via FedEx with no extra shipping charges. A VERY nice transaction I must say!
Last night after I got home from work I figured I'd get a head start on todays project & attempt to get the old receiver off. Sprayed the nuts & bolts with some Zep & let 'em soak for 30 mins. Hit them with the impact gun & they zipped right off, 6 nuts & it came right out. Right about then I'm thinking to myself, "this was FAR too easy"
I guess I just figured being that the TV ( '99 GMC Suburban 2500 )
being "old" & raised in the North (MN & WI ) that the removal of such an item as a hitch would not have gone so smooth. I'm sure I'll pay for it today during the install of it's replacement.
The '99 Suburban, from everything I've read, did'nt come with any "real" factory tow wiring. (even though there was a factory tow package) it seems most use a "t-connector" wiring adapter, which you insert in-line at a lighting junction under the rear of the truck, and it provides you with a straight 4 pin connector, which you then wire to another adapter to convert that to a standard 7 blade round RV connector ( you also have to find the factory brake controller wiring loom & add in the additional wires for the trailer brake function part of the deal)

In the process of the removal of the old hitch & making some sence of the old wiring last night, I found what I think is basicly all the wiring one would need to wire up a complete 7 pin RV plug. The posts I've been reading all have stated that GM ran a wire loom that carried two heavy gauge wires (orange & blue) from under the main fuse box in the engine compartment, to an area under the rear of the truck (drivers side) These wires you needed to wire into your 7 pin harness in the rear and also to power up front in the engine compartment.
What I found in the wire loom was indeed the heavy gauge blue & orange wires, but also a heavy gauge white, and 4 lighter gauge wires coded brown, yellow, dark green & light green.
I'm guessing with a little investigative homework, I'm gonna find that these wires are all I needed to completely wire up my 7way plug. Granted, I've already got the adapter, and it's pretty much "plug & play" with that thing, I would have rather had wired everything in direct & not messed with an adapter. (they always fail eventually at some point)
During my process today, I'll try to take a few pics & see if I can manage to get a few to post for anyone interested to see.

[truxpin]

So far it has all gone better than I expected. The wire loom I found with not only the heavy gauge orange & bluewires also had a heavy gauge white and lighter gauge yellow, brown, white, green, light green.
They all ran up the frame and into the engine compartment where the orange had a metal loop on the end and in a sufficient length to make it into the main fuse box to one of two Aux. 12 volt 30 amp terminals. ( this will serve as the charging line to the trailer batteries when the trailer is plugged into the TV. ) the heavy blue had a "capped" end ( this one will get ran back in & under the dash to the brake controller) , the heavy white ran to the frame for ground and all the lighter gauge colors ran into a fancy connector near the main wiring harness, after a bit of testing I found out they all performed the correct duty (brake, left signal, right signal, etc....)
In essence, I could have bypassed the T-adapter for the wiring to the 7 way plug, but being that I already had purchased it and also purchased a 7 blade plug with a 4 way adapter on it, I decided to just go with it. I DID however tap into the light green wire to supply the 7 way plug with reverse lights.




Here's the new location for the wiring harness. The old one is hanging below still....
I removed the existing license plate light and drilled a pilot hole a 1/4" straight below it and then drilled a 2" hole around the existing smaller hole left from the light.
I would advise some careful measuring BEFORE you do this , to make sure your harness is going to cover the new larger hole in the bumper AND to be sure that the harness is going to sit flush agianst the flat part of the bumper. If you go to low, you'll be into the bottom curvature of the bumper lip.









A nice close up of the relocation












Finished product. You can see I removed one of the license lights and drilled a 2" hole and installed the plug harness in it's spot. I figured this would be a more secure and better looking spot for it than hanging it on a bracket under the bumper.
Now today , I tackle the other end....the brake controller!

[PhilipKS]

Did the Curt bolt up fine? Looks nice! A Curt Class V HD is on my list. I'm not comfortable with the OEM on my burb.

CURT Manufacturing | CURT Manufacturing - CURT Trailer Hitch #15524

[truxpin]

Originally Posted by PhilipKS

Did the Curt bolt up fine? ..... I'm not comfortable with the OEM on my burb.

It fit like it was made to be there! Nice & straight and no warp in it's construction.
I'm glad I went ahead and removed all the old OEM bolts, I can see where you'd be tempted to re-use the old ones (or some of them anyways) The two closest to the rear of the truck are the easy ones(you can actually put your fingers on them) The other ones are not quite as accessable as they are located inside the boxed part of the frame. They were easy enough to get out, and after seeing them I'm glad I went throught the trouble (see pic)





Nor really what I want to trust an 8000lb trailer on.

Anyways, after I removed all the bolts I wire brushed as much as I could, blew out all the "build-up" with compressed air and put in the new bolts.
The Curt hitch came with everything I needed except some thread locker (blue)
Even came with a nice little curved wire that you can use to get the new bolts int place inside the boxed frame sections, that supisingly worked very good!
Torqued them all to 75ft/lbs and it's good to go. I think I spent about 3 hours total start to finish, about half of that was spent "gabbin' " & drinking beer.