abominable z71

Tim are you willing to be the lab rat? I'll etch out a second board soon, we can put them on your rig and see how they do in the real world for a few weeks, If they work properly on the 6.2 it should be fine on everything else.

level struts, are replacement struts that are longer than factory to level the front end with the rear. Search rancho quick lifts, they are a full replacement spring and everything. The bilsteins are just the strut itself, you disassemble your factory assembly and replace the strut with a longer one and reuse your spring and top hat and hardware. The end result is something about 3/4-1" longer than OEM raising the front end about 2" give or take.

Magnuson Moss act put's the onus on the manufacture to prove you're aftermarket parts caused whatever issue they are trying not to warranty. In the case of the vibrations even though after market wheels and tires are not the cause it's hard to argue that they have to address the situation without having the factory wheels on the truck it's just an easy out for them to not touch your truck.

Tested out the circuit yesterday afternoon. Works like a champ. Best part about it, it doesn't require any additional wiring to power the relay, power comes right from the turn signal. Tap the turn signal wire tap the ground for the coil side of the relay then break the DRL wire and run each side of the drl wire to the contacts on the relay. You can't post video on this forum but here's a link to my dropbox that has a short video. I didn't have anyone to help me test it so I had to put the truck in neutral to get the DRL's on and activate the turn signal to test it so I wasn't able to shut the turn signal off and show the DRL come back on in the video. Now I need to make another one for the passenger side and do some longer term testing to make sure they don't fail after a few days of use. Radio shack sells everything you need to build these you just have to be comfortable etching traces on copper clad plate and soldering to build a circuit board. I'm going to check the amp draw on the DRL and see if I can find a relay that fit's the bill that isn't PCB mount to make it easier for anyone to make one of these. https://www.dropbox.com/s/4hgj0hvfyoa6xtm/DRL%20shutoff.mp4?dl=0

I'm hoping to have time to test out my circuit this weekend. I like the DRL on with turn signal so I haven't really put it at the top of the priority list.

Did you replace your axles and R & P? If so did it fix your problem?

The circuit to do this is pretty simple, only takes a few components paired up with a normally closed relay, It's just the relay coil impedance that might mess with the BCM turn signal function when it sees 360 ohms of coil resistance, maybe nothing

I have a prototype control board built for the DRL just need to cut it in and test it. It's bench tested and works fine my only concern is once it's cut in, i'm not sure how the additional resistance of the relay coil is going to affect the computer for the turn signal flash, I may have to pull the 6 ohm load resistor and run a different resistor in parallel with the cut off. The weather was just too nice this weekend to do any wrenching, when you saw me on Saturday we were headed up to Bass Lake.

Finally got a chance to snap a Pic of the finished install.

You got lucky getting Harry Hogge as your service writer.

Interesting, I believe you may be the first that said the pico scope is saying lateral run out issues. Let us know what they find if anything.

LT is just a light truck designation it doesn't dictate load rating. LT ratings breakdown like so: F rated tires are 12 ply equivalent, E rated tires are 10 ply equivalents, D rated are 8 ply, C are 6. Passenger or P rated tires are 4 ply equivalent. Ply equivalents don't tell you anything about the actual load rating. These are the numbers that follow like 125R or 126Q. The number is it's load rating and the letter is the speed rating you can find the charts on line for each but you would have to contact the manufacture for the correct pressure for your exact tire, the charts on Toyos website are for their tires specifically but pretty close in general probably within 1-3 PSI.

Damn thing also has to be in gear.

Yeah exactly just need to load the electrical system to tell the BCM to increase the duty cycle, most people don't have a battery tester to go that route though so you have to improvise and create some load another way.

I was thinking the same thing, the wire is short enough that the resistance is a little less than the passenger side. Like you said this is a tough one to test since you have a 5 minute window to catch it and the vehicle has to be in gear for the DRL's to turn on. Maybe there are more flickering problems. The voltage output on the these trucks is determined by a multitude of things and cab be anywhere from 11 V at 10% duty cycle to 15.5 V at 90% duty cycle. I think during the initial start-up before the truck is warm its going into a charge mode with a higher voltage output just high enough to cause issues. The truck warms up and a lower duty cycle charge mode is selected, the voltage drops and the issue goes away. Try this for a test. After the truck has warmed up, Turn on everything you can to create and electrical Demand, Heated seats or cooled if you got them, AC at full blast, Rear defogger on, This may or may not create a condition to get the alternator into a higher output to test and see if the DRL flickers with the turn signal activated.

Do you know if Tim's is flickering on the drivers side as well?

and reasonably priced at 200 Dollars for 25 dollars in material and 30 minutes of labor.

When you say it only flickers when the truck is cold, do you mean after initial start-up after the truck has been sitting, or will it do it if you shut the truck off and start it back up regardless of whether the engine is warmed up or not?

I don't see anything showing a difference in the wiring for the 6.2. Perhaps you and Tim have the bigger 170 amp alternator which shouldn't cause an issue, or do either of you have the dual battery set-up? I didn't realize Tim was having an issue with flickering as well.

Just for kicks replace the 20A fuse in location number 6 on the left side fuse block. This fuse block is behind a panel on the side of the dash on the drivers side.

Everyone of these trucks does not shake. We have 4 identical trucks, sierra crew cab slt z71 4x4's and mine is the only one that shakes. Vibration frequency felt through the seat and console is exactly 3x the tire speed frequency. A NVH issue requires three components. A source, a transmitter and a receiver remove any one of the three and there is no longer an NVH issue plain and simple. Roating components. wheels tires rotors drive shafts gears transmission engine etc. are all sources, frame, mounts body seats all transmitters and the driver is the receiver. So while blaming the body mounts is plausible because they are part of the transmission path and specifically the part of the transmission path meant to mitigate vibrations there is a problem with that statement. The problem with saying they are designed to shake and the reason you feel it is the body mounts is that only a handful of them shake and the ones that do, shake at varying levels of amplitude. They all share the same mount design. Where each truck differs is the tolerances of the rotating components and the way their tolerances stack together, just look at one corner of a 4wd truck. you have a tire, rim, hub assy. rotor, and CV shaft all rotating together, Each with a potential for mass imbalance, lateral and radial run out. now every one of these items can be within design spec individually. now consider the possibility that every item in the assy. is on the ragged ass edge of acceptable for passing a QC test. you now have a tolerance stack on your rotating assy of 5 plus parts. Now is where rigidity of the frame, cab and shear design on the body mounts reveals it's ugly truth. It's not nearly forgiving enough to isolate the receiver ie, you the driver from feeling the result. and this is what makes the issue so hard to repair, you tear the truck down to find the source and start measuring all your parts and what do you find... everyone of them is within spec although on the edge still within spec and there's no way the manufacture is going to replace a part that is within specifications, no smoking gun is found they road force and balance your tires for the 8th time and off they send you. So really both sides of the argument are correct there is a vibration source problem and a transmission problem, fixing either one will solve the vibration felt by the receiver. But if you ask GM I'm sure they'll tell you the problem isn't the source or the transmission components its the receiver and the receiver just needs to deal with it. If the problem was with the connection of the motor and tranny to the frame these trucks should vibrate at all different speeds not 68-80 mph like they do, and further more the vibration is exactly the same at 72 mph whether in 4,5 or 6th gear which puts the engine and tranny at all different RPM's.

I did, it doesn't matter if the resistor goes to ground or is cut in parallel like shown.

E and H are junctioned down stream of the X50A connector. Essentially the same wire. So you connect one of the park lamp signals into the run crank on pin 6?

The 17 upfitter shows the same pin out as the 16. If the pins had changed the head light wouldn't function properly right from the get go. I'd get a multimeter and check the resistance from the X50a connector to the x110 connector, and from the turn signal wire to the drl. Resistance connector to connector on the DRL wire should be a fraction of an ohm the only resistance should be due to the length of the wire and from the turn to the DRL should show open circuit or something along those lines depending on the multimeter you use.

What do you connect it to? There isn't a run1/ign signal coming down on the 14/15 harness. Do you have a multimeter?