lurker_007

I traded mine on a ZR2 2500 gas last month and have not had the issue. Currently in Tennessee about 1200 miles into the trip with no messages on the new truck

I’m sure it just depends on what part it is, where it’s coming from and where the strikes are happening. Ordered a new trailer camera through the dealer parts department last week. Came in 3 days later. Have a friend needing lifters replaced in a Tahoe with a 5.3. Lifters and all other hardware came in, but still waiting on a gasket for over 3 weeks.

I have owned both gas and diesel 2020+ HD trucks. I currently own a 2024 gas 3500 that I traded a 2023 3500 diesel for and have a gas ZR2 on order that will hopefully be here soon. I use my truck as a daily driver but also pull my 12,000lb 5th wheel around 10,000 miles a year. I’ve pulled it with both gas and diesel all over the eastern United States from the flatlands southeastern us to the mountains of Virginia and WV. The gas is more than enough for 99% of HD truck buyers. No def, no emissions related issues, cheaper fuel. Also me personally, I average about 14.5-16 mpg unloaded with my gas on my daily commute. I averaged 15ish with the diesel. Towing I average 8.5-9.5 with the gas and averaged 9.5-10.5 with the diesel. So no real MPG benefit for me. Also save about $11,000 upfront compared to the diesel. For me it’s a nobrainer but if you’re pulling 15,000lbs plus on a daily basis, sure get the diesel. If you live out west and climb 8000-10,000 ft regularly? Get the diesel. But as for me, GAS all day. The diesel certainly has its place, I’m just honest enough with myself to know that I don’t need it. You will get the occasional person that says “hey nice truck.” And then followed by “Oh man, you don’t have the diesel!” At the end of the day, your money, your choice. I for one, don’t care to get other dudes rocked up at the red light over the chitter chatter of my duramax.

The battery quick disconnect will cut power to the 12v fridge and everything else inside the coach that runs on 12 volt ie. the interior lights, vent fans, water pump etc. The point I was making is that the brake issue is due to the trailer battery back feeding into the truck. The battery will still back feed into the truck even with the quick disconnect turned on because it only cuts the circuit to the internal 12v system of the rv. The running lights, brakes, and battery will still be powered and connected to the truck which wil cause the module to shutdown and give you brake issues.

Keep in mind that the battery quick disconnect only disconnects the 12v power going to the coach from the battery, but not from the truck to the battery or from the battery to the truck. That was the first thing I tried when troubleshooting after reading the bulletin. You’ll need to disconnect the negative lead from the battery to actually prevent the battery from back feeding. Or do as the others have suggested and wire in a diode. Not sure what timeline you have but I couldn’t get one local and had to order one on Amazon. If you can’t get one and wire it in before your trip, turning the battery disconnect will only kill power to your refrigerator but still give you the error message and turn off your brakes.

How far of a trip are you taking? If you plug the rv in the day before and let the fridge and its contents get good and cold well before your trip, it will essentially act as a cooler when not powered on. Or do you have a propane option? I have another older travel trailer, the fridge only works on shore power. I’ve camped with it several times by letting it all get cold for a few days before we left. The day of the trip it will stay cold well over 9 hrs of driving until I get to the campground.

Opened the bulletin today and it has been updated to include the terms "trailer with a battery" instead of just solar/generator. Fix is to replace the brake module with an updated part which I'm pretty sure is just the old brake control module from the previous trucks.

My tech heard back from an engineer today. Looks like the current remedy is to replace the brake control module with the old version found in the pre 2024 trucks. My tech ordered one based on the old part number and is hoping that gm doesn’t send the new version since it’s vin specific. Will update once I know more. Thanks.

Hopefully the fix is out soon. This weekend we went on a 200 mile trip to North Ga and pulled it home today another 200 miles. With our trailer battery disconnected we had zero connection messages or brake malfunctions. The diode came in while I was out of town so I may wire that up this week if I get a chance. For anyone curious, I ordered the RoadMaster RM690 from Amazon. Should work for this issue if the 12v back feeding is the correct cause of the problems. Will update whenever I can.

This is probably my biggest concern. The technicians have told me that the truck monitors for a connection to the lights and brakes but they're separate circuits. When it thinks that the trailer doesn't have brakes, it doesn't send the braking signal to the trailer. So if there is ever an issue with your trailer wiring or trailer brakes, the truck will default to think that there is no reason to send a brake signal. This is DANGEROUS. Now with this new TSB it seems that the module actually shuts down all together. Any other after market brake controller will always send the brake signal through the 7 way plug whether it has brakes or not. This is a much safer design. Absolutley insane to me

Just updating to say that I pulled the trailer home last night with the battery disconnected and didn’t have a single warning light. This seems to have worked so far. I will look at possibly wiring in a diode on the trailer to prevent back feeding until GM releases a fix. This way I will still have a battery on the trailer and power to the brakes in the event of an emergency.

Just commenting to share my similar experience. I work at a Chevy store and I have a 2024 Siverado 3500 srw gas and a 2021 Coachmen 298RLS fifth wheel. I have towed this trailer with 5 different trucks and never had an issue. I got my new truck a few months ago and pulled my trailer from Savannah, Ga. to Ft Wilderness (Disney in Orlando) trip was flawless all the way there aside from a tire blowing out. The day we hooked up to come home I couldn't get the trailer brakes to work no matter if I plugged it into the bed or bumper. After trouble shooting for an hour we decided to just try to limp it home and drive slow. The manual override (factory brake controller wouldn't work) and there was no braking at the trailer axles. I figured out that the trailer brakes would randomly come on in full force after stepping on the brake pedal or 10 or more seconds... Which then as long as I squeezed the controller it would actually work. But as soon as I let off the controller or foot brake I would get the "check trailer connection" warning and no longer have brakes. So I adjusted my gain down and limped home allowing the brakes to kick on after 10-15 seconds of holding the brake pedal each time. We stopped in Daytona to fill up and shut the truck off for 30 mins or so and pretty much the truck worked normally for the remainder of the trip. SInce then we have put another 1,200 miles on the truck and trailer and have learned to drive it cautiously. I have had my dealership look at my truck multiple times (at least 5) and they've made me ride around with a trailer simulator and a homemade brake magnet tester to trick the truck into thinking it had trailer brakes hooked up. It has never given a warning with either of their testers so they've informed me that gm says that it's my trailer, not the truck per GM tech line. The issue is, this happens with my other bumper pull travel trailer as well. This trailer pulled fine behind all of my other trucks as well as my wife's 1500 and our Tahoe. But with my truck it gives me the "check trailer connection" and no brakes. In the last few months I've talked my dealership into replacing the brake controller on my truck as well as the module up above the spare tire. I have also hacked into my new trailer wiring and put a new Pollak style connector per GM's request. None of it has made any difference. I also hooked up two other new 2500 HD trucks to my trailer and got no warning messages. I did this with a 2024 Custom which has the old interior and software as well as a 2024 LTZ that has the new interior like mine. Neither truck gave me a warning message. Fast forward to today when I found this thread. Sure enough my vin has this TSB attached to it. Although I do not have solar or a generator it almost exactly describes what is happening to me. This morning I actually pulled my trailer to work as we were camping over the weekend. I towed the trailer about 30 miles to work this morning and had the warning message pop up at least 45 times.. I stopped counting. After letting the tech diagnose and plug his pc into the truck to record what was happening to no avail and him saying that gm is saying that it's my trailer again... I decided to google it some more and found this thread. After brainstorming, I decided to disconnect my negative battery terminal on my trailer effectively stopping any possibilty of backfeeding. I then pulled it around about 6 miles and had no warning messages and the brakes worked flawlessly. I will pull it home tonight (about 15 miles) and see if I still have luck. Only making this post as I do NOT have solar or run a generator while traveling. My truck does have the 220amp alt and the aux battery but I can't imagine that causing my battery to be overcharged in the trailer. I understand that my breakaway cable wont work without the battery connected but I feel it is safer for me to have functioning brakes while towing until this is resolved. I will update if anything changes. Just wanted to share as this may be a bigger issue than just for those with solar or a generator. Thanks

I’m not sure how extensive the flushing procedure was. I do know that they flushed and filled the transmission after the work was done. Odd part is that the jerking happens at the same rpm range every time. Might be about to trade for a diesel

It very well could be torque converter shudder. However they replaced the torque converter under warranty and it is still doing it. So idk what the odds of both of them being bad are. I also installed timbrens last week to adjust the ride height thinking it may be drive line vibrations from the load changing the angle. Although it handles better and doesn’t squat as much now, it’s still jerking at that rpm range.

Sorry everyone. I know this is an older thread but I have been searching for weeks and came across this today which almost describes my situation perfectly. Looooong time reader (5 years or more) but I have never joined up until today. But I was hoping for some insight from anyone on this post or familiar with this issue. I have a 2021 2500HD 6.6 gas. I pull a fifth wheel of around 11,500 lbs. My issue is when I am accelerating while towing I start getting a jerking/misfire "fishbite" feel starting around 3000 rpm up to about 4000 rpm. This started at about 12,000 miles on the truck. It mainly happens in 3rd gear between 3200 rpm and 3800rpm but has started doing it in the end of 2nd gear and even 4th occasionally. I brought the truck to the dealer with the trailer attached and the tech rode with me. He felt it as well. He brought along a laptop that was connected to my truck. He recorded some snap shots of all the data while it was doing it. The data was submitted to GM and they noted that the slip speed was more than tolerances allotted. They recommended replacing the torque converted and inspecting the trans pump. My pump had a few cracks so he replaced the pump rotor and torque converter. I was hoping for it to be over. However once I hooked to my trailer again, it was still there. Just as bad as before. We did another test drive and recorded the data again but he and another tech seem to be at a loss as to what is going on. Just FYI it does it with or without tow/haul engaged, cruise on or off, air conditioning on or off, stabilitrac on or off... none of it matters. I have even pulled it without the trailer plugged into the electrical to eliminate any trailer brake malfunctions... It happens around the same RPM every single time. I have pulled 4 other trailers the heaviest of them weighing about 7000lbs all bumper pull. No issues present on any of them. I am waiting to hear back from the dealership still but looking for answers on my own Thanks!!