Whipped500

Sorry for the delay, I thought I replied to this...must have not hit submit. 21-NA-267 is what they did but not sure what all they tested. Their incompetence with my whole experience tell me they replaced the valve and called it good. I got it back and it still smells like exhaust when first starting and cold temps. The second time it went in, it wasn't that cold so they started making excuses. Not sure what is going on with the coolant. After 16k miles the coolant tank is down about 3/4". I'm thinking it too is temp sensitive like the exhaust or it had an air bubble. They pressure tested it but never filled it back up to where it should be after not finding anything...they did it twice or I should say didn't. The second time it went in, the write-up even stated low coolant. The DEF, I personally think the tank is bad. One time I was driving and it went from 1/2 to counting down to reduced power. After a few key cycles it was back to 1/2 for a few thousand miles/couple months. It did it a second time, again at a 1/2 tank. It went from 1/2 to counting down reduced power. This time it wouldn't go away though. I was down to 100 miles before 65mph I think was the speed. I finally had to put a jug in so I can keep driving until my appointment. After putting a 2.5 gal jug in, it went up to 3/4 (2 bars missing) and has been there since. All they did to it was a TSB update...which just fixed the injector from not turning on right away. This dealership (Raymond Chevrolet in Antioch, IL) is so incompetent, it's not even funny. I have caught the mechanics drinking on lunch break. This should have been a huge red flag but they kept insisting they have the best diesel techs in the area! A buddy had also told me he had a discussion with one of the diesel techs and said he was very knowledgeable...which is the only reason I gave them a shot. I learned that they are nothing but parts changers. They can only do something if a light is on and the scanner tells them what to change! They actually probably wasted more time thinking of the excuses to tell me than it would take to test things. End rant...I think LOL

I actually didn't buy from this dealer either but I heard from someone that they had a good diesel tech and also the dealer kept bragging that they have the best diesel tech around! Apparently this means that if there is a light on that they can plug a scanner in to be told what part to replace or a TSB, then maybe so? Otherwise it's just excuses! What really bothers me the most is that one of the problems was exhaust smell in the cabin...exhaust smell tells me carbon monoxide...they tried telling me its fine and every vehicle does it. There was a TSB about this and they did replace an exhaust valve but it still didn't fix the problem and now they don't want to do anymore.

Does GM have a complaint department for their dealer network and how to go about it? Quick synopsis...took my LM2 in for some things that needed some attention. Get it back and immediately had concerns that anything was fixed. By the next day, I figured out nothing was fixed. Took it back a second time and still nothing. 1. Coolant level low 2. Exhaust smell in cabin 3. DEF I can elaborate if anyone would like?

Any other symptoms? I took a trip last weekend to go snowmobiling. I left with 2 lines/lights down from full on the gauge. I was pulling a 2 place snowmobile trailer with 2 sleds so nothing heavy at all but had a bad headwind. By the time I got to the hotel, I was down to half a tank (went down 2 more lines) but figured that was from the headwind. Came back home with no wind and was a real nice easy drive. I kept an eye on the DeF gauge and everything was fine until about 75 miles from home. I watched it go from half a tank to 1000 mile warning to 500 miles until power reduce all within minutes. This happened before once but it ended up going back to normal...this time it didn't correct itself and kept counting down until I put more DEF in.

Actually not looking to spend much at all because it would be more of a code reader. Maybe if I was towing or going a longer distance would I have it on to check different readings.

I was assuming all I needed was the Bluetooth thing to plug in, but I was looking at a cheap ELM earlier and it said it wasn't compatible with diesel. O didn't know it mattered. I thought the app did everything. I'm open to any device as well as app but otherwise I was going to use torque or torque pro.

I mainly want it to read codes but I am also interested I'm trying to look at other things that I have heard people mention they can do...exhaust soot level, def fluid level, regen

Anyone have any recommendations for a Bluetooth OBD2 to link to my phone for Torque? I had one and can't find it so was going to get a new one to for my LM2 since I'm getting DEF problems. Looking for suggestions and basically wondering if there is anything that makes one better than another or just get the cheapest? Thanks

If it smells the same, then I can't be sure what I'm smelling...but as my tank shows, it is losing it somewhere.

14,600. Charge tank is fine/maintaining. Never been topped off

I've been keeping an eye on it since new. It was at the correct level when new, but now it is low.

Have a 2020 LM2 Duramax with 14,600 miles. Since day one I've smelled antifreeze but reading on here, everyone seems to say it is nothing to worry about. Well I am sure it is losing it now. When cool, it is about 1/2" below where it should be on the coolant bottle...where is it going? It's dry underneath. Motor is dry and no drips/puddles. I've seen a few threads talking about this but never a resolution. I am concerned about this and want to get it fixed because if it is burning it, I'm sure it isn't good for the DPF! I also think that by the time it does something very harmful to the DPF, it would be out of warranty. I am going to make an appointment at the dealer, it's just that I don't have a lot of confidence in dealer mechanics lately, especially if the scanner doesn't have a code to tell them to replace something. Just wondering if anyone has had this and have gotten fixed so I can have something to push back with if they say they can't find anything and just fill it to send me on my and tell me to keep an eye on it.

What is confusing me is I seem to regen about every other day (while using the BP), but since using the Mobil, it's been 2-3 times the whole tank. It seems I regen a lot more...but my driving is also short, local trips so I attributed it to that.

This is in my LM2, my LML doesn't get driven in the winter

I know I should try both with my additive to see the outcome but.... Would going with BP and the opti-lube possibly bring back the power/MPG and lower emissions/regens...hypothetically? Would running the Mobil be a wise choice in warmer months when they aren't cutting the fuel for cold weather in IL/WI? What confused me about everything is that with less regens I figured better mileage. I also figured the cetane was higher to make it burn cleaner for less regens...but like I said, it seems lacking a little power. At this point I almost feel the less regens is better than the mile or two MPG because i use this truck for work which is a lot of short distance service calls.