Clifford, the big red truck. 8.1l 2500HD with M101 bed.

[Jrgunn5150]

I've hit a bit of a stumbling block on the tail lights.

When I wired up the new lights, the tail and brake lights worked correctly, but the blinkers just made them light up like the brakes were applied. Since I have LED front lights, I think it may be an issue with using all LED's, that's my current theory anyway. I have an electronic flasher that will be here tomorrow to try and rectify that.

 

[locrwln]

Do your taillights have only one bulb that does the braking/turn indicating? If so, you will need a separate bulb for the turn signals. I ran into the same problem with my flatbed and had to add a separate turn signal indicator. The GMT800 rear light system is set up for the brake and turns to be on separate leads. Or, you can tap into your trailer harness and use that to feed your rear lights and ignore the factory rear light harness.

Jack

 

[Jrgunn5150]

Do your taillights have only one bulb that does the braking/turn indicating? If so, you will need a separate bulb for the turn signals. I ran into the same problem with my flatbed and had to add a separate turn signal indicator. The GMT800 rear light system is set up for the brake and turns to be on separate leads. Or, you can tap into your trailer harness and use that to feed your rear lights and ignore the factory rear light harness.

Jack

So I have one light, brake/tail/blink per side. Is that what you mean? Because there are many LEDs in that one light per side. I'm assuming they would all blink, but it does explain the issue I'm having. Bummer, I really don't want to add another light, especially since I already blew those holes.

 

[locrwln]

This is the way my flatbed came:

I had only one light. Normally, on any other truck to include the GMT400 and the GMT 900, that would work. But for the GMT 800, they had a separate circuit that ran the turn signal, so you can't just bundle everything together and wire it up. The taillight/brake light circuit is one light and the turn signal is another light.

I had to do this:

Of course afterwards, I was told that I could have just used the trailer wiring circuit and it would have ran the single light just like it was a trailer to keep the factory bed/taillight system out of it.

Jack

 

[Jrgunn5150]

Understood, I've done the same thing. Bummer, now I have a decision to make lol.

 

[Jrgunn5150]

I'm not sure what's going on with my turn signals, I have a flaky ground or something. Brake lights and tail lights work fine. Blinkers work fine until the head lights come on. It's like 60 mph and 25 degrees outside right now, a literal blizzard, people fail to signal all the time, so I'll live with it for the time being until I can spend some time with a multimeter and figure it out.



I was somewhat curious if the loose canvas would be a detriment in being able to heat it, so i picked the worst day of the year to figure it out lol. Used my Mr Heater 18000 BTU from my garage, had to turn it down to medium, it was blasting me out. I think a diesel heater will work well in here for cold nights, I don't intend to actually winter camp with it.

 

[496bb]

Awesome! Love my 8.1!! Blackbear tune really woke up the available torque too.

 

[Jrgunn5150]

Awesome! Love my 8.1!! Blackbear tune really woke up the available torque too.

Yeah I have HP Tuners, I was surprised at how much they hobble the thing from the factory. For instance right off throttle timing drops to like 5 degrees lol.

 

[Jrgunn5150]

 

[Jrgunn5150]

Idiot neighbor called the cops over the oil burner, cops told him he's a retard... I managed to get pretty far,

 

[Jrgunn5150]

I was sitting at my desk Friday and all the lights went out at like 10am lol, so instead of heading to our other location, I took the opportunity to get out in the woods for the day.

Clifford did much better than I expected, but the lack of front travel is pretty harsh.

 

[Pacific Northwest yetti]

Looks great! When i switched to a flatbed and the LED;s i had some weird things come up. I just tied into the trailer wire harness, made a " jumper" so if it ever goes bad/ugly i can unplug that stock jumper and drop a new one in. I also had to add a manual flash module. And it messed w/ my cruise. I made sure the center mounted stop was still bulb, and it worked again.

look forward to seeing this evolve. I have the 6.0 and have thought a lot about the 8.1, and differences it would of made. I am happy with my rig though

 

[Jrgunn5150]

So, the tailight thing was bugging me, and it's warmer, or it was yesterday, so I tore into the truck with a multimeter and did a little DOE... When I unhooked the front harness, the turn signals worked fine, so I pulled the grille and took a peek. Butt connectors, Scotchlocks, splices, electrical tape everywhere....

I'm fine with basic wiring, but I'm not tracing all that. Went to the yard and pulled a uncut harness, 22 bucks. All my lights work correctly again. To bad it failed exactly when I changed the bed, sent me in the wrong direction forever.

Also, we're going to look at a truck bed camper today.

 

[ejs262]

jeez... sounds like my luck, except you were able to find a new harness!

 

[Jrgunn5150]

jeez... sounds like my luck, except you were able to find a new harness!

Yeah, I'll never buy another ex-plow truck again. They covered the plow up well, took the brackets, and all the controller stuff, but looking around, I can see that's what was going on.