Chadw90

It doesnt impede the passenger’s legroom? i mounted it to my step assist handle tonight.

Just a little 2.5lb fella

Does anyone have a fire extinguisher mounted in the bed of a new HD? Ive always carried one and has always been under the back seat. For some reason when i moved my stuff over to this new truck, i left out the extinguisher. Saturday reminded me on why one is necessary. I seen a truck and camper pulled over on the side of the road, a circle of residual from a fire extinguisher around a wheel, guessing a bearing failed. That guy saved his camper. i want to mount one in the bed due to my rear seat being fully loaded on trips.(children’s snacks, toys, dog kennel, etc) so accessibility would be minimal. anyone have pictures of one mounted in the bed?

I can say that Bilstein 5100s make a significant difference. I rarely drive my diesels with no load or trailer on. My 2017 had 30,000kms and I was driving unloaded one day and it was like a pogo stick. I pulled the lower rear shock bolts and the shocks were flat. Wore right out. I was over the 3yr warranty period so I put Bilsteins on. The truck never rode that smooth even from new. They will not soften the ride as they are stiffer, but adversely they work better due to the stiffer design not allowing the truck to float or bounce. The ride is much more controlled if that makes sense. The truck stays more planted and doesnt feel like an old farm truck. I want to change out the Rancho’s on my 2023 but it’s just not a priority when they havent failed yet.

Regular lead acid,no solar charger.

so i was in a mad panic today to leave to the lake. I pulled the battery posts off the trailer battery and the brakes worked 100% the whole 300kms trip. Not sure if its a coincidence. Maybe a diode on the charge circuit is needed?

No idea Marv, Just as I think everything is working properly, this $100K truck lets me down again. Hooked it up to a new camper tonight, leaving the lot, i grabbed the manual slider, BAM, brakes so hard and fast it would scare you. Get out on the highway and a kite behind the trailer would create more drag than the brakes on gain 10 and manually engaged to 100%. But with more fiddling around and paying extra attention, under 40km/hr, they work good. The faster you go the less effective they are. And I know before someone goes into the theory of inertia, i get it, but this is like you can hardly tell if the exhaust brake or trans braking is doing the work. I actually turned both off to try. Now is there an issue with the pre 24’s and trailer battery back feeding once charged? If GM designed the braking logic this way, the engineer must have fell on his noodle. This is 100% opposite to a new Ford if you’ve driven one, they dial back the braking at low speeds to accommodate for inertia and to prevent lockup at city speeds or around corners for those who like to run a higher gain. Im not even sure what to do now other than trade out of this into a dodge or ford. Like i told the dealer, 95% of people do a tug test when taking off and forget about it. Id like to talk to GM tech support directly because as per my resume, I understand the theory of electrical better than the techs working on these trucks at the dealers around here. Any good tech from automotive in this area gets poached by companies like me or my competitors lol. Damn karma! where are you from Marv? Canada I presume? I recall you referencing kilometres in a post. I will keep you updated as I dig further into this.

I replaced the gain switch/controller and my brakes started working fine again. Made a couple trips with two different trailers and then after the second trip, same thing again, no trailer brakes. took my truck in and they replaced the module by the spare tire, and the gain switch again. The module was failing the gain switch.

Exact same

Module replaced amperage prior to module replacement was 10.2 amps. Hooked up to the same trailer, amperage is now 14.4 amps.

Mine goes in tomorrow for the module replaced. i will test the amperage as soon as its replaced.

Yes, to the point where the rims and hubs are hot from excessive drag.

Update: Put a 9000lb load on a 2500lb trailer and hit the road. All way good for the first few brake applications and then all of a sudden no brakes again. Exact same issue as before. It was working fine for the last few trips. Something is either failing that switch or have a major coincidence that after replacing it that it worked for the next 1000kms pulling just fine. Mechanic told me that it might just be the intelligence of the truck that it dials the braking back. Yes, GM has it programmed to turn the braking effort right down while towing. I just rolled my eyes. I said today that I cant drive this truck being it is unsafe to tow with. I left it with the trailer and load at the dealership today.

Yep, the manual one on the dash. It appeared to be working, no reason the believe it didnt other than process if elimination. Dealer changed the 7pin plug. I replaced the whole brake system and if it would signal out to the module in the back on gain 10 and using manually, then the module was receiving signal. So for under $75, it was worth a shot.

Wow, I missed a lot of good feedback. BUT just as this mechanic with a heavy electrical background suspected, it was the simple controller/switch (we will call it gain control for simplicity). Swapped it out for the $67 it was and just like that, magically have brakes. As my original thought right from the start had it, the gain controller was NFG from new. Numbers increased and decreased like it should, but not enough output from it. Its like it had 0,0,0,0,0,0,0,1,2,3 gain settings. Either way, I sure do appreciate all of you taking the time out of your busy day to dig into this and help. Tons of good information on this thread down different avenues, that Im sure it is going to help many people with similar issues but needing different results. If it werent for forums like this and people like you, we’d be handcuffed to the competency of our local dealers and unfortunately some of us would not be as fortunate as others. again, thanks everyone!

The dealer doesnt seem interested enough to investigate any further. They have replaced the 7 pin plug and reprogrammed.

Yes it does, but I dont think the controller is working properly. You can have the gain at 10, and manually squeeze it all the way and the brakes hardly drag. hook up to a different trailer and same thing Hook up with a Ford and brakes lock up immediately. I put a 10,000lb skidsteer on a trailer with the Ford and it will skid the tires on the trailer with the gain turned to 10. With my GMC, you can hardly feel the brakes drag.

The OEM one. And thats CAD, not USD

I see that some people with the 2024 models are installing aftermarket controllers. It will be the day that I add one of those to my truck. I will trade it on a Ford before I start adding aftermarket equipment to a truck built with it already integrated. OEM controller is $65. Im going to install a new one out of pocket and if it works, then the service manager and myself are going to have a real long conversation on how he will somehow compensate me for the trailer brakes and wiring. Ive put over $1000 into brakes and wiring on my trailer for obviously no reason. Ive asked for a case to be started with GM, but they must look at it as defeat because they really dig their heels in when I suggest it. Who knows, maybe GM comes back and says yes, we’ve seen this and here is the fix. How come I see GM reps reply to some posts on here wanting to look into the issue, I dont ever seem to get someone from GM interested in my issues lol. Probably because we are from Canada, we are just a drop in the ocean for GM.

Had this done to mine too. Had lots of clunking when backing up and turning while hooked up to a trailer. Clunking is all gone now.

Well had another wheel alignment. Weird, it was off again. Go figure. No answer to why after 5000kms we are doing an alignment again. Theres a TSB for the popping from the rear leaf springs. It works. Ive put on 600kms since and no popping at all. TSB 21-NA-138

Did you ever get this taken care of? I have a 2023 2500hd and have the EXACT same issues you are having. Set controller to gain of 10 and barely feel a tug when manually activating. Replaced all four brakes, lead harness(assembly, did not fab one). And then ran all brand new wiring from the junction box to the brake assemblies. Literally everything is brand new. Went to work and grabbed a brand new trailer and still the same issue. Hooked a Ford Super Duty up to my trailer, works like a brand new braking system(go figure) They even had to lathe my rotors because they were warped after hauling a 13,000lb load a couple times. GM has replaced my 7 pin connector and re flashed the computer. Still no fix. I think the brake controller isnt putting out enough amps. The parts department has sold many of them he said and have 5 brake controllers in stock. Not sure what else to do.

Same here. 2023 GMC 2500 AT4 Tires cupping at 10,000kms, wheel alignment done under warranty. Steering wheel off center at 20,000km service, wheel alignment performed and charged to me. 25,000kms now and steering wheel off center again. Dealership is A+ and I have no concerns with competency to perform an alignment. Something is up with these trucks. Im a ticketed mechanic by trade and should put it up on my hoist and inspect it myself, but I dont buy $100k+ trucks with warranty to have to work on them at all, let alone do it myself. Wish GM would do a better job supporting dealers in regards to publishing a fix to a problem rather than just say they havent seen this before. I work for John Deere and JD makes every effort to minimize customer-dealer conflict by having a department at the other end of the phone when a tech has a one off issue, they can call and talk directly to a rep that collects data from all over the world, and can point them to the problem right away. In the auto industry, they more or less just wing it.

I seen the relay bank under the dash for each switch, so there is no reason to wire in a relay for a lightbar? Just use the wire lead for whichever switch i want? The gauge of wire isn’t that big, which had me believe that I would need to wire in a relay before my light. Confusing as it seems redundant to have two relays if the under dash ones wont carry the load.

I got an email yesterday about my AT4 order, will be here end of September/early October. Price increase was the first thing I asked about, but dealer claims I am price protected due to me trading my previous truck back in February and I do have a signed sales contract(I even have a copy of this contract). The salesman said the only thing they cannot guarantee is interest rate as that is set by bank if Canada, but as a dealership they will do their best to make the end of term cost of the truck the same as what i signed for. Keep in mind Im only needing to finance this truck for about 16 months, so this would be a minimal price adjustment for them.