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Last night I went out to test fit some stuff in the bed and the powered cover wasn't cooperating. Didn't think to record a video last night, but it was still doing it this morning, so this time I did.

Took the Hummer back to the dealer this morning to have them address the whistling noise and the cover. They said they would have to get GM involved in fixing it, and GM might decide to send out the tonneau manufacturer for that part. I opted to have them figure out what needs to get done, and drop the truck off once they have a plan in place. If it's just going to sit, I'd rather it sit in my driveway.
UGH .... some definite troubles right out of the gate. GM Quality Control should have caught the windshield issue. The power tonneau cover most likely is temp issue; ice perhaps in the actual enclosure or a motor adjustment issue. I am now second guessing the power cover. Maybe the manual trifold BAK Flip MX4 hard tonneau would be best. Anyone else having issues with the tonneau?? Hang in there Dark-fx..... hopefully the issues are resolved quickly.

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Dealer confirmed the whistling was coming from the area where the windshield meets the trim on the passenger side. Also confirmed the tonneau cover is still having issues for them as well. Hopefully they can get GM technical support to assist now.
Dark-Fx ~ any update on the window and tonneau? Fixed yet? Cause of tonneau I am guessing was ice?

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Very distinct whistling noise. First driving the truck it was noticeable at 35+ if there were cross winds, over 55 if it was calm out. Today anything over 30 mph is whistling, and louder than freeway speeds before they tried to fix it. Without the whistling it's just white noise, which is a normal sound. Volume of it might be affected by the exact positioning of the windshield but I don't know that enough yet.
Dark-FX did they square away the tonneau cover. Is it working properly now?

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I put almost 400 miles on my truck this weekend after picking it up on Saturday morning. I spent Saturday with my toddler son in the truck, so my driving was a little more reserved than getting a real test in. I'll touch more on that aspect of it later

EV Stuff: The good
One pedal mode. Once figuring out that there was an option to enable in the infotainment system, I was pretty impressed by it. At first with the D/L that my 2018 Bolt had, my expectation was just that "L" was the one pedal mode. If you don't enable the one through the infotainment system, the truck will still creep at low speeds unless you come to a complete stop while holding down the paddle. The strength in just "L" seemed comparable to what was in the Bolt and in my Polestar 2. After enabling the explicit one pedal mode, using the paddle, and having the battery level pretty low, the truck will come to a complete stop doing 10 over the speed limit at a yellow light way before the traffic light if you don't modulate the throttle. With the battery at around 75%, the strength was still adequate for stopping. I didn't spend a lot of time with a battery more full than that, but my expectation is that it might be necessary to supplement with the actual brake pedal.

Range for around town driving is actually quite good, even for winter time. I'd expect to get pretty close to the 329 mile range that the EPA estimates. With how inefficient the truck is normally, cabin heating doesn't seem like it's going to take a big chunk out of the range. Maybe 5-8% on the worst days.

Remote precondition gives you an entire hour of time. I'm not sure how long it actually takes for the cabin to warm up, but the hour is likely because it's also trying to warm the enormous battery. I'll want to take some more observations and testing here to be sure of it. You are able to set the desired cabin temperature from in the app after you've started preconditioning.

EV Stuff: The okay
Throttle response at low speeds is a bit touchy. That's probably partly due to getting used to the polestar's pedal that requires quite a bit of movement to transition from low speeds to actually driving, but that method definitely translates to improved maneuverability at low speeds. I'd like to have options here.

At high speeds, it's really easy to get going too fast since you're only using the bottom 10-15% of the available powerband. A little bit of pedal adds a lot of power. Cruise control at 80 mph seemed to hover between 70 and 130kW of usage depending on hills. Full pedal on the floor at highway speeds is something around 750kW. I had to make a concerted effort to take my eyes off the road to check it. It wouldn't take long to get up to nearly 100 mph when you are already doing 70 mph. I haven't topped the truck out yet, but it felt pretty stable at all speeds I've driven it.

WTF Mode. It's definitely faster. 0-30 in normal mode feels like it's probably slower than my Polestar2, but WTF mode is way faster. It's hard to really gauge it because of all the gimmicky stuff the truck does. Lowered suspension, vibrating seat, loud whirring noises coming from the speaker system. If there was an option to turn that crap off I would. That's why I'm only rating it as "okay" here. I'd like an option to turn all of the artificial sounds off in normal mode as well.

Charge rate seems like it's going to be adequate, but because of the amount of energy consumed, it's going to be really important to have properly working 350kW stations. On a 125/62.5kW chargepoint, being the only vehicle, the hummer was getting just over 110kW, which would be a great speed in other EVs, but would mean about an hour of charging for every two on the freeway in the Hummer. 350kW stations seem to be considerably faster, More info about my testing at an EA station here.

EV Stuff: The bad
Obviously, energy consumption on the freeway. They probably put a lot of time into improving this, but at the end of the day, it's still a huge truck with exposed front tires, and it's terrible. If your only option is public charging at DCFC stations, it's probably just as expensive to drive with gas at $3/gal as a gas pickup on the freeway. I posted some detailed info about my highway testing here.

Transitioning off cruise control. In other cars, I have been able to pick up how to transition off of cruise back to normal driving without the vehicle surging forward or backward. I haven't quite figured out what to do in the Hummer. I'm not sure if pedal position is just different with it or what. More about this further down.

Truck stuff: The good
I took a detour on my drive on Sunday to go down a dirt road that I knew was in terrible shape. I put it into offroad mode, not sure if I needed to, but I did. The truck had no problems maintaining 50 mph down some of the worst washboard and big potholes in the roadbed that I've ever seen. It just soaked everything up. I don't have a lot of experience with trucks that are upgraded for off-road, but I was definitely impressed. Would have been scraping the bottom of my Bolt with the straight line I took through everything, and probably blown out a tire.

Fit and finish of the truck seems good. I didn't spend a lot of time going over everything with a fine toothed comb. I do have a few complaints that I will probably try to have addressed by the dealer, I'll put them under "okay"

I ordered the hard power tonneau. It works well, haven't loaded anything into the bed yet. I can just barely see the buttons, I think my wife would have to locate them by feel. The multi-pro tailgate seems like an absolute necessity for getting in and out of the bed, since the bed is up so high and the bumper doesn't have any steps. My last truck was a lowered GMC Sonoma where my feet could practically touch the ground sitting on the end of the tailgate, so it's going to take getting used to. I plan on taking some measurements at some point but haven't yet. The tonneau roll does seem to take up quite a bit of space.

Four wheel steering is amazing for tight parking lots. It definitely makes the truck feel smaller than it is. I'm able to do u-turns easily in spaces that would be a tight fit for my Polestar.

The camera system is pretty good. I have top-down views in other vehicles, but there's something about the hummer one that feels different, so I probably just need to get used to it.

The center of gravity being so low with the batteries and motor being below the cabin seem to help a lot with how it feels going around corners. Less body roll than I would expect from a truck of this size because of it.

Truck stuff: The okay
I am getting a whistling noise near the top of the windshield on the passenger side on the freeway. Cross winds seem to make it much worse. The volume of it is fairly subdued, so I'm able to ignore it. Overall the truck has a lot of wind noise, but, better than the jeep 4xe I test drove. Worse than my Polestar 2 with a bike on the roof.

The "soft open" for the tailgate doesn't always descend from just hitting the buttons.

The frunk buttons are a little weird. Remote says "2x" but hitting it 2x only seems to make the truck acknowledge the request. Have to do the same 2x again for it to open. Have only opened it a handful of time, so I'm not actually sure if I'm doing something wrong. It does still open.

The rear seats seem to have a lot of room, but I had to move my seat slightly forward when putting the rear-facing child seat in the back behind my seat. Still in a comfortable enough position for me, but someone much taller would likely have issues.

The buttons for changing ride height seem sort of non-responsive. UI lag here and other places in the infotainment system are very noticeable. Putting the truck in park-assist mode, I wasn't sure if I actually depressed the switches properly because it wasn't even coming up.

Truck stuff: The bad
It's a truck. Getting my son into the rear facing car seat means having to lift him to chest height with extended arms. The opening is a lot tighter than it seems like it should be, but it's probably because of the up-right seating configuration that I'm not used to.

The OEM tires on the truck are not great on ice. With rear-steering turned on, it is extremely easy to have the rear end get kicked out around low speed corners. I'll have to experiment with turning it off when entering my subdivision because it's just one giant sheet of ice right now. My polestar 2 with winter tires, I can just drive 25 mph around the icy corners no problem. If I had actually gotten the truck in Fall, I probably would have considered getting winter specific tires for it.

Supercruise: The good
Seems to work really well when there isn't a lot of traffic and the roads are straight and have good lines. Automatic lane change will overtake to the left and return afterwards without having to do anything. It's fairly predictable in optimal conditions. It tracks around corners pretty well. Hands off works great in these conditions.

Supercruise: The okay
In heavier traffic, it's less predictable. It might just be my lack of experience with it, but it's really strange being responsible for driving while something else is actually doing it. If it's not able to change lanes, it will slow down and keep speed with the vehicle in front. When the left lane clears up it will start the automatic passing if you have it enabled. I will probably turn the automatic lane change off for that reason.

It tracks lane markings too well in turns. Some of the highway I drove on have lane markings that don't have a smooth radius to them. I drive these roads all the time but never noticed it. Sudden sharp correction to continue driving in the center of the lane. With how wide the truck is, it's a little bit disconcerting to actually use supercruise on busy non-straight roads. Part of that might be because I'm not used to driving a vehicle this wide either.

Supercruise: The bad
Super cruise dropping out is really confusing, as there is a lot going on. Messages, flashing lights. Kind of overloads my brain, but I'm sure that's the point. I think immediately as it drops out it requires you to take over the accelerator, and that could be part of my confusion. If it happens three times in a drive, it locks supercruise out until the next key cycle. I had it drop out twice in the exact same spot when I was doing my consumption testing. It wasn't due to not paying attention, there was no flashing blue light telling me to pay attention, just immediately flashing red. I tried to re-enable it immediately the second time and it locked me out for the rest of the trip.

It can start lane changes it won't complete if the vehicle is driving into a sharp corner. Taking over to complete it results in confusion of "who" is actually driving now. That's probably the worst aspect of supercruise, but again, might just be because I'm not used to it.

Other stuff:
The wind noise and jounce of the vehicle put my son to sleep pretty quickly. Problem is it was a few hours before his normal nap time so it screwed up the rest of my Saturday. It's going to be great for road trips because of that, but it's something I will have to be aware of when we schedule activities. He is two, so his nap schedule is still pretty important.

I'd like to test out how well it pulls a trailer, but I'm not sure if I will have time to in the next few weeks.

I plan on taking some measurements for different things, seeing if my coolers will fit in the frunk/bed. If anyone has suggestions for things they'd like me to measure or look at, I'd be happy to take some photos.
Back in February when you wrote this, gas $3.00 bucks a gallon..... 😂🤣

"EV Stuff: The bad
Obviously, energy consumption on the freeway. They probably put a lot of time into improving this, but at the end of the day, it's still a huge truck with exposed front tires, and it's terrible. If your only option is public charging at DCFC stations, it's probably just as expensive to drive with gas at $3/gal as a gas pickup on the freeway. I posted some detailed info about my highway testing here."
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