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Anyone that could help shed some light on this issue ive ran into on my 2003 Gmc Sierra 2500hd 4x4. Recently installed a non torison bar drop cognito 6 inch lift. The kit came with torsion keys which I installed. Currently the trucks sitting 2 inches above max ride height with the adjuster bolt basically fully backed out with the keys just sitting on the nut. If i were to attempt to clock the key one hex back it would hit the cross member. I have contacted cognito but havnt heard anything yet. Anyone run into this before or ran a cognito lift?

New to the this forum but a seasoned vet on others. I’m posting to see if anyone else is having brake issues after the TSB for the brakes on the 3500 L5P. If not to keep an eye out. Long story short, we just finished a 12 day camping trip up the coast of California. On the last day we headed home which is 4 hours away pulling our 5th wheel. (2023 Momentum 395M). 30 minutes from home, We were getting on the interchange and noticed some clear white smoke corresponding with my break pumps. On the third pump I lower my trailer breaks thinking it was set too high cause of the steep grades. Pumped again and that’s when I got a steady white smoke. Pulled over right away and inspected to find fluid leaking in front of the driver rear tire and a small fire. First thing I do is shut off the truck. Run around and get my wife out of the truck so we can kids and dogs out. As I turn around my 4 year is strapped in his car seat with flames all up the rear door and back glass. It happened so slow and fast at the same time. All I could think about is that glass breaking and the oxygen sucking the flames in and watching my son burn to death in front of my eyes and I can’t do a damn thing. I did indeed get him out and the family in to the trailer. We were stuck in what I call the kill box now. It’s 2 major freeways that interchange in to a 2 lane highway with at least 1/4 of concrete barrier on both sides with no turn outs not too much further up. We were lucky to stop where we where. We tried to put out the fire out with 4 extinguishers between the truck driver, tow truck driver and myself with no anvil. At this point I have to either get my family out of the trailer or unhook and try to drive off. Well ….. we were able to unhook. Jumped in the truck knowing turning on the fuel pump was a terrible idea. The thought of my family sitting on the upper deck on top of 2 propane bombs under them just gave me the push I needed to commit. Turned her on and floored it. The truck had exploded with me in it. I still remember seeing the flames all around, the heat and smoke in the cab. I was able to exit the vehicle after that excess fuel to burn off. I suspect that the initial fire started on the passenger rear and moved to the driver rear. As there are tire stamps from the right rear some something hot, melting or leaking for over 80 feet. Where I stopped first. You could see that it was leaking where the tires would be. Puddle is wet on the right side and the left is burned. if fuel was leaking, there would be a fuel burn line or fire. This is what I think happened but we will have to wait and see what the experts say. We are very fortunate that there were no injury or fatalities. Insurance company has taken custody of the truck and investigation is pending. I only have 17k left on the loan and had 15k of parts and labor in to it. Mods were as follows. 35x12.5 wrapped on 20” Fuel Triton wheel, K&N drop in filter, S&B 62 gallon fuel tank, Retrax hard roll up bed cover, B&W 5th wheel hitch and custom mudflaps. All I know is that I almost lost my family, trailer and truck that I’m most likely going to lose on. 3500 was purchased certified used last June around 14,000 miles and burned down last Thursday with about 16k on it. Now the adrenaline and shock has worn off. The anger and ptsd is kicking in. We wouldn’t have gotten out with our skin suits with out the help of the kings if all kings …God, the 2 Good Samaritan and our great first responders. In the end of the day I have my family and health and thankful for that. I’ll be posting my outcome, as soon as I hear back and case is closed.

I have a 2019 L5P with 72k on it. Bought it last June from a dealership with 51k on it. Few months ago, I tried to go get it aligned at a Big O and was told they couldn't do it because it needed new pitman, idler, and inner tie rods. Got it on the lift few days later and decided pitman and idler were getting replaced, but tie rods didn't seem bad. Bought the parts, took it to a reputable shop, and had them replace them and align it. They scoped out the tie rods and agreed they weren't bad. Fast forward to a week ago, truck is out of alignment again and has slowly been getting worse. I have play in my steering wheel, rides rough, and discovered today that my ball joint on my driver side lower control arm is leaking grease. Once again checked my tie rods and still mechanically appear fine. I won't lie, I do not know all there is to know about these trucks, and I've been learning as I go. With all this being said, I'm looking for any information, any tips, any things to look for, or even common problems that I may need to look out for in the future. I'm on my own trying to figure this all out and the only thing most other shops do around here is treat me like a dumb blonde chick. Last shop I took it to is booked out now for over a month or I'd go back there. Any help would be greatly appreciated.

Hello I am looking at buying a 21 duramax and I noticed that some have a GVWR of 11,150 than and others have a GVWR of 10,000. I’m curious if there is an actual difference in parts or engineering or is it only for registration purposes? Any information is helpful, thanks!

I am looking to add an elevated idle feature to my 2018 Chevy sliverado 3500 duramax Dually. My truck is currently not set up with the pto feature. I currently idle my truck for about an hour a day and I am wanting to add an elevated idle to get my truck to operating temp faster to prolong the life of my truck. What are y’all adding to the truck for aftermarket parts to achieve this since the dealer is saying it’s not possible with gm parts. What else are y’all running for tuners to increase mpg that will work great with a fully deleted truck.

I purchased a 2023 2500hd LTZ DURAMAX in January. Truck drove and handled great until a few days ago. The other day I started feeling the rear end wandering and swaying on me. Anything over 65 is an accident waiting to happen because it can get all over the place. Noticed that if I shake my driver side rear wheel it clicks loudly. Checked lugs and everything else for tightness and everything is tight. Truck now has 25,000 miles it and up until 3 days ago was perfect. Any ideas or insights would be greatly appreciated. Thank you. 20230922_203351_1.mp4

I purchased a 2023 2500hd LTZ DURAMAX in January. Truck drove and handled great until a few days ago. The other day I started feeling the rear end wandering and swaying on me. Anything over 65 is an accident waiting to happen because it can get all over the place. Noticed that if I shake my driver side rear wheel it clicks loudly. Checked lugs and everything else for tightness and everything is tight. Truck now has 25,000 miles it and up until 3 days ago was perfect. Any ideas or insights would be greatly appreciated. Thank you. 20230922_203351_1.mp4

Hello, I am about to buy a 6.6L Duramax 14' 2500hd Sierra with 136K on it. But I just learned it has a small heating core leak, the dealer is replacing the whole core prior to purchase. Should I proceed with this purchase? Or is this the sign of this truck going down hill. The service recorded were regular until 2018 then the car fax no longer shows any updates. Any help would be appreciated, I have a 92 Sierra with a 5.7L small block so the diesel world I am not as comfortable with. Also do not want a newer truck as I do not want to deal with DEF and I would not be able to do a delete.

So recently I cracked the bell housing to my transmission and it lost all the oil, so I’ve been looking at good used transmissions. My question is what years are compatible with the 2006s? I’ve heard the plugs vary year to year making some incompatible with different years. Any advice would be awesome.

2020 2500 Duramax. Is anyone else having problems with their trailer lights? I’m having problems with the lights on all but one of my three trailers. Left turn signal and brake is not working. Took it to the dealer and they gave me some bs about how the truck can’t run led lights or more than 10 amps and blew me off. So essentially my brand new truck I bought for towing can’t tow a trailer with more than two tail lights. One of the two it isn’t working on is led and one is not and it runs the led lights just fine, just not the left turn or brake on both.

Chevrolet recommends AC Delco Diesel Exhaust Fluid in 2021 Sliverado HD Duramax. Is their a difference in AC Vs Blue? Most Stores don't carry AC brand.. is it worth ordering online or is any DEF fluid okay?

Anyone have issues with a coolant leak the dealer “can’t find”. I bought my l5p denali duramax about 6 months ago and have put 15k on it in those 6 months. Mostly used for pulling my 43’ fifthwheel. Anyway the issue. At 3k the low coolant light came on and I brought it to the dealer. I was told air had not been properly removed from the cooling system when assembled so they burped it and I was on my way. I was good till 11k miles. At 11k the light came on again and I brought it in. The radiator was replaced, brought it home and started it a couple days later and the coolant light came on. Called the dealer same story burping air out so I topped it off myself. 11k noticed coolant puddle under it and coolant drips on passenger frame rail by front bumper. Brought it in and dealer couldn’t find a leak so I took it home. Two days later the coolant light came on and multiple drips were on the frame. So at this point I have executive GM involved with trying to figure it out. A couple things at this point have me worked up. Not one time was I offered a loaner car not once. After the radiator was replaced they put The plastic skid plate one under the radiator and broke it and left it on. So now I want a loaner when I drop it off. I wait almost a month before they give in and give me one and bring the truck back in. At this point the over flow is almost empty so it’s not leaking very fast. The truck now has 15k on it. I bring it it in and get a loaner car for the first time with 15k on it and the 4th visit in 6 months. Dealer still can not find a leak. I asked them to climb under they truck and look at the frame rail for coolant. He calls back and says it’s dry. So I send my wife to pick the truck up. She drives 15 miles home from the dealer and that’s it. When I got home from work I checked under the truck and it’s dripping coolant. So a couple of things so far, executive GM has done not one thing to help me out. I have done everything myself. They don’t return calls and do not return emails. The last time I brought my truck in the dealer refused to give me any paperwork showing that they actually looked at it they just gave me paperwork from my previous visit. He service advisor keeps telling me it’s burping out air and it’s residual coolant from the radiator replacement 4K miles ago and 2 months ago. I don’t know what to do. I have lost all respect for GM and their product.

new here. just throwing this out there to see if anyone has info on how hard it is to convert the front bumper on a 2006 Silverado 2500HD to a 2018 Silverado 2500HD or what needs to be done to get it done. heres a picture i found on Facebook of it done. just need more info.

Brand new oem bosch injectors for an LML 2011 through 2016. $2,600 for the complete set of (8) shipped anywhere in the contiguous U.S. NO cores are required.

This question has probably been answered on here a hundred times over but I can't seem to find any search results that match exactly what I'm looking for. My dad has 07 Classic with the LBZ Duramax. He absolutely loves the truck and plans on running it til the day he dies. With that being said, his biggest complaint is the fuel mileage he gets out of it. He averages 12-14MPG no matter how he drives it even when towing our boats/campers. He keeps sending me links to sketchy sites with tuners that are dirt cheap and claim to greatly improve fuel mileage. I'm smart enough to know not to go cheap when it comes to tuners/programmers. Can anyone provide any recommendations on somewhat affordable tuners that increase fuel mileage enough to warrant buying one in the first place? Or any other ideas to help squeeze some more MPGs out of it? Any input is greatly appreciated!

I have a 2020 GMC 2500 AT4 Duramax Diesel. Fuel economy is normally 18-20 mpg local and 21-25 mpg highway. I've noticed multiple times that if I completely fill the tank up, that my instantaneous fuel economy and average drop significantly. Instantaneously runs about 8-12 mpg and my average over the last 50 miles drops down to 11-13 mpg. Then suddenly after about 25-50 miles of driving, it will jump right back up to good fuel mileage. If I never completely fill the tank, this doesn't happen. Dealer says they've never heard of this, but I don't trust dealership feedback. Previously I had reported multiple times that DEF fluid levels were completely wrong and erratic and they said there were no reports about it. Then miraculously there was a software recall that fixed it.

I have a 2003 Chevy 2500hd 6.6l diesel. All gears and shifting were working fine. Pulled out on highway today and had to get on it. When going through gears I heard it slip up and rev as if it slipped out of gear. I slowed down and got off road. It seemed to be stuck in 3rd gear. I tried putting it into reverse and it would not work. The shifter doesn’t even feel like it’s moving into gear when I move into reverse. When I move shifter to Drive, it sounds very rough and it starts off in 3rd gear. The truck will not shift out of this stuck gear, not even go into reverse. Had to put home slowly in that gear range. Need some help, What’s going on?

I have a 2001 2500 HD with ZF6 6 speed manual transmission 4*4, I bought the truck at a deal and am finding out why......it's a unicorn...lol. I am just a blue collar worker like most of the rest of us and can't afford the $3500 price tag on a rebuilt trans especially since I don't have a $1000 core transmission to trade them. I still have the transfer case and driveshafts and all other parts to the 4*4 trans..I found a 2wd ZF6 6 speed trans with only 140,*** miles on it I can get at a steal and am wondering if I can change tail shaft and make the 2wd into a 4*4 transmission? Any help would be greatly appreciated even possibly part #'s if possible.....I guess I can drive the truck as a 2wd if I have to but 4wd is one reason I bought the truck....BTW this is my first diesel so any and all help is appreciated..... ONE I WILLIE

I am reaching out to our community. If you own a model year 2020 Silverado/Sierra 2500/3500 DURAMAX Please attach a video clip of the instrument cluster while traveling down a grade(hill) and applying the brake briefly to activate the Auto grade brake feature. I am really looking for early production vehicles here but any and all that are MODEL YEAR 2020 will help, the earlier the better. This will not take long and your help will be GREATLY appreciated!! Please note the production date of your vehicle this can be found on the B-pillar placard. Also if the vehicle has been into the dealership for any service/recall/SIB that required your vehicle to programmed(updated software) please note that as well. THANK YOU!!!!!!

8070 miles So as I take off from a stop sign the truck seems to be lugging and I guess you’d call it bucking. If I hard accelerate it goes away. It’s only at low rpm. It’s at the dealer now for three days and they tell me they are talking to Gm engineers and truck could be there for a week or two minimum! Obviously after spending 90k$ Not what I want to hear. They’ve never had this problem before. I did need to put it in four wheel drive for a few min to get out of some loose sand on construction site. But put it back in 2 wheel with no problem. Anyone have this problem. Of course I’m also supposed to be going on a 1500 mile trip in ten days. Not feeling real comfortable with this truck now!! Please help!!!