6.6HD

I am so glad you mentioned top tier fuel! The mechanic said the same thing. I am a bit embarrassed that I didn't know what the heck he was talking about. Well, I knew some companies had better gas than others... I knew some companies had more additives than others... But, I didn't know anything about Top Tier Fuel. I looked into the matter once I got home and sure enough... So, anyway.. learn something new every day... Lucky for me, Costco is on the list and there is right one right down the road from me. So, to put the matter of a catch can to bed for once and for all (there are endless threads about the subject out there), and since the inception of the 6.6 there has been lots of questions about whether its built in oil separator is enough, I think I can safely say: 1. Almost any DI engine can benefit from a can. 2. The warranty issue cant be answered in a black and white way. You must figure that one out for yourself. 3. Almost every DI engine should be fueled with a top tier fuel if you can. By the way, I had a can on my '17 1500 and still have two full mason jars filled with oil that I dumped from it over three years. I am a big believer in them. My quest was about this new 6.6. There is a lot of marketing material out there stating that there is a built in oil separator and they spent a lot of time and engineering trying to solve the issue. For me, case closed.

Catch can is much like a Oil/Water separator. A catch can is only relevant for a DI engine. There is so much info out there... do a bit of googling for more info.

Dang... whats with all the sour grapes?? I didn't say I was an expert on anything. ...and of course I noticed when the one cylinder went nuts... it went into the shop each and every time it dropped. I think someone woke up on the wrong side of the bed today. Or, perhaps you got your weewee caught in your tail pipe this morning. ...dang dude... relax and be nice. No need for such talk. We are all here to pass on information about our trucks.

Great question. One I did not think to ask... and, frankly, I dont know if its possible to determine that. Regardless... For me, the can is going on due to the intake being coated in oil. The mechanic was very clear that it was "coated" and that a can would mitigate it. That is enough reason for me and I am not concerned about the warranty because, with this truck, its an easy on and off (easier than the 1500). So, if needed, I can take the can off before going to the dealership.

I will make this very long story as short as possible. Less than 10K. Many trips to dealer due to engine light and running rough and also going into reduced power mode. Finally able to identify bad injector in one of the cylinders. They replaced it. When I picked up the truck, the mechanic showed me the injector. Reminder... less than 10k on the motor. There was already coking and carbon deposits on it. I went on to ask the mechanic if the intake had oil in it. He said the intake was coated in oil. I said, "So, this engine will benefit from a catch can...?". The mechanic said, "It will for sure". I had one on my '17 1500 that I emptied regularly. I have yet to put it on my 2500. After my conversation with the mechanic, I will be putting that can on this truck ASAP. Will it void your warranty is the obvious next question... it depends on the dealership. There is no pat answer to this. So, if your worried about it... and your truck is still under factory warranty... ask your dealership... If they say it does then go to another dealership. The one I used could care less that I had a can on my 1500. No more discussion needed guys and gals.

I have been looking for an answer to this for a while. I finally saw someone run one on the new 6.6 gas and they were collecting oil. So, that is a yes. It wont void the warranty.

I had the same issue. I took it to dealership. Its a bad motor in the mirror. They replaced the entire drivers side mirror. They both close at same rate now.

Where does the outflow connect? To the top of the throttle body or bottom?

Parking brake and rough running: I have had this same issue since I drove it off the lot. It would occasionally do it. Almost always after using trailer or offroad mode then going back to normal mode. Finally took it in. They did get some good codes. All I know is it is some issue with the #4 cylinder. I will updated you as soon as I get specifics and also a solution.

2020 2500HD LT Crew 6.6 w/ All Star Package - has them on all 4 doors

I have 18's. Crew cab. Any idea on part number for the torsion bars I would need? Maybe I will just mount a couple hundred pounds in iron blocks under the front bumper! LOL

I have the 6.6 Gas and the snow plow prep. I dont plow and would love to tame the ride (its a bit rough). Will upgrading the Bilstiens help? Or, maybe crank down the torsion bars? If upgrading shocks, do I need to consider the plow prep when order shocks? thx!

Dude, I was in the same boat some months ago. Then I found the 2020 2500HD LT w/ the 6.6 gas. I like it better than the 6.2 and takes regular gas. The 6 speed is a def upgrade over the old 6 speed. No clunking. Smooth as silk. Oh... and no cylinder deactivation. No shut down at stop... Iron block 400... whats not to love! Like all the new models, the new 2500's are not without their issues. However, I am so happy I got it over the 6.2 trail boss.

Three alignments. 1 Tire rotation. Mine still pulls right. Sometimes real bad...

These trucks have all kinds of steering issues. There is no fix as of yet.

Mine pulls to the right also. Three trips to the dealer and still pulls. They cant fix it. I dont have the other issues you are seeing at high speed. I love this truck. I love everything about it... I wish they would fix the steering. Had I known how bad the steering was, honestly, I probably would have gone with a FO**. For those looking at the new HD's from Chevy/GMC - test drive the crap out of it. Take it to the interstate. If it doesn't drive straight, you must understand that THERE IS, AS OF NOW, NO FIX FOR IT.

Perfect description of my truck. I have been back to the dealership three times for the steering. Three alignments later, multiple tire rotations and It still wanders all over the road and still does not drive straight. These trucks have steering issues. You will see owners talking about it all over the forums with steering issues manifesting in many different ways. I sure hope its not a safety issue. Frankly, I dont know what else to do.

2020 2500 LT 6.6 Gas. I do have plow prep. No Shutters. Build date 6/22/2020

Are there any downsides to doing this?

Same problem as all of you. Taking it back for third alignment. I will demand a new steering box. Wish me luck!

I have noticed the same thing. Must push the brake hard and deep. Truck creeps forward at lights and stop signs. If you pump the brake one time, you will notice it tighten up and feel good and sensitive. I hope its not a safety issue. Why when you pump does it then feel right? You guys notice that?

i drop it around town to 55 all the way around. 60/70 when towing.

I think GM has a winner here with the new HD. I hate to see them have more issues with supply. Dealers cant keep them in stock as it is...

Holy Toledo! Glad you and your wife are ok!!

The ability to see engine hours and idle hours is most likely for fleet/commercial use. Idle time is a big cost for fleets. As someone involved in fleet management... most systems that measure idle time do so by the following (numbers may vary) Anything under 1000rpm for X amount of seconds or minutes starts the idle time ticking... Again, I dont know what GM considers idle.. but it will be something like that. So, its possible that coming to a stop sign/light will increment some idle time. Again, this is for fleet customers where you may have 100 trucks and if each is idling and hour or two per day... that's big money!!