[SilverDan]

😁 😁 😁 😇 😇 😇 😇 😇 😍😍😍😍😍😭😭😭😭🥳🥳🥳🥳🥳🥳🥳🤩🤩🤩🤩

 

[SilverDan]

478 miles 👀👀

Now where's the TB4?

 

[SilverDan]

"said Joe Roy, chief engineer for Silverado EV "

So Nicole Krantz (sp?) is on to greener pastures.

 

[SilverDan]

That's a lot of promotions and already in management. She's got the relaxed manner that makes for promotion so no surprise. This will continue until the Peter Principle kicks in, which is you get promoted to the level of your incompetence 😅 It's true actually ...

I made top tier engineering but never management despite a few tries, I made the mistake of being too good an engineer. Avoid being a good engineer if you want promotion, good ones are too valuable to lose so if you want to rise in the ranks you have to kind of suck as an engineer.

 

[SilverDan]

I was watching the dirt ride for wind tunnel aero performance, the dust giving visuals.

40s mark
You can‘t tell from the still but if you watch the sequence it sure looks like it’s reforming those air streams from the bed and the bottom. Certainly I’m not seeing much turbulence in general

35s mark
Looks like low turbulence right behind the truck which is what you want. This shot is picture perfect, that dirt stream off the back is so perfect it almost looks like an artist created it for a aniumation. Notice how much it looks like contrails, which form from the highly aerodynamic airplane wing/engine

37s mark
If you watch the sequence you see the dirt kicked up by the front tire doesn’t get sucked under the truck which would mess with that flow presumably, instead it just quietly is outside the envelope. Also clearly shows low turbulence off the back

At 57s the angle clearly shows the surface turbulence getting kicked out of the way as you’d want. And fascinatingly the kick off is pretty much the same no matter the steering toe out/in, he does some turns but it doesn’t really affect this part

The acceleration at the end shows it better as the tires dig in and kick off more dirt. Interesting in that it appears like it’s the front motor doing all the work with the back little changed 🤔
You can also see the truck rear up - notice the back well is squatting

56s mark
Dirt pulled up by the tire is in a quiet zone, it just kind of drifts off, not a lot of turbulence in that wheel well it seems which is what you want - it’s not getting turbulence from the outside

Even in the macho money shot notice all that manly dirt clouds are just from the tires banging through that loose stuff, the ambient clouds the truck is driving through are relatively undisturbed. The messy lower section is just from the impact of the tires hitting mounds of fine sifted dirt, but look at that ambient along the top - beautiful! Also I think we get a hint of the sail action

Anyhow this isn’t remotely definitive, and may not be unique to the SEV. I looked for other truck dirt videos but didn’t see anything comparable. Maybe some interesting clues though

 

[SilverDan]

The Tire looks like a Goodyear Wrangler Territory AT @flyinglow

Here’s the lettering and tread more clearly

So I believe this then is the tire, except the tread isn’t the same. Maybe an EV variant or something.

https://www.goodyear.com/en_US/tires/wrangler-territory-at-light-truck/24365-73330083800000.html

 

[SilverDan]

More aero prn from the back, there’s really little turbulence back there

 

[SilverDan]

I wonder where they are finding these massive efficiency gains.

You mean they weren't previously?

I wouldn't be surprised. SiC is still relatively new believe it or not and just getting deployed the last few years. But these boards are developed years before release, they need to be in the finished proto's, at least two years (depending) ahead for QA and qualification tests (road testing).

So SEV released a few years ago which means those boards were developed say three years previously when SiC wasn't in the prime time yet which was 5+ years ago. Feels right we'd be seeing this silicon about now which was from board revs say three years ago when SiC was coming out in production quantities. They would have known about it already and had engineering samples but it has to be worked into the timeline.

Well that's explain a lot, this silicon is much more efficient, I'd love to see the internal numbers between the two boards. Now this also includes the new freewheel vampire improvement too right? All together a substantial 28 miles (at GM's conservative estimate), that's awesome.

And I was wrong, I was not expecting a lot of improvements in successive MY's, but I wasn't taking into account Ultium. This is now their number one business, already we are seeing a chemistry change in a few years (lower $$) and small but substantial range improvements.

 

[SilverDan]

What is hydraulic rebound control? How is that different from a shock absorber?

I would have guessed a hydraulic bump stop except they only comes into play on bound, not rebound. Could it be adaptive shocks with adjustable rebound valving?

You're the shock expert not me in the slightest but I wonder if they're using this now?

General Motors Magnetic Ride Control

Magnetic Ride Control (MRC or MagneRide) is a General Motors chassis and suspension technology that adapts and adjusts the shock absorbers of a vehicle in real-time in response to changes in terrain in order to deliver optimal shock damping for the best possible driving experience.

Been around for a while but according to AI search has not been on the TB, which instead 'features a Z71 suspensions package with factory lift and Rancho shocks".

Given the weight of this vehicle the ICE suspension probably won't work, but maybe this system would be the treat. Slamming 9k lbs over potholes would need something special to keep from slamming around I'd think.

 

[SilverDan]

That'll be 525 miles easy on the road, just drive like me 😅

 

[SilverDan]

I think around 520 was the record going 100% to zero but with a lot of 70 mph. I actually think getting - who knows - 530+ should be possible with under 60 and a bit of hypermiling. I don't know why the YouTubers aren't trying this, seeing how high they can get, it would make a great video. They just run and gun. The first one to get 550 miles would be a big splash.

 

[SilverDan]

Not a whisper on lockers in anything I've seen published for the 2026 SEV Trail Boss.

At this point I'm getting the feeling they're holding back something to make a splash at the public reveal Andre is going to. They're carefully teasing this out, full order guide is out (except suspension), then teaser with a mysterious 'hydro suspension' (whatever), so keep your hopes up

 

[SilverDan]

Also with those 22”/24” one concern for me is road noise, I’m not fond of the short sidewalls they have on the Bolt which gives too much road feel and noise.

You guys know from my blathering that I was long planning the Max LT, but damn if the off roadies aren’t compelling packages. Knowing the range just seals the deal. Only - the only downside for me is no underbody wheel storage. I’ll have to keep a spare in the bed. But totally worth it since the tradeoff is lots of sidewall cushion, AT and doesn’t hurt range enough to matter.

 

[SilverDan]

When was the last time you had a flat?

Agree, around the house I may keep it in the garage. But traveling my trailer has a full sized spare on board so dumb not to have one for the truck too. Getting stranded with a trailer is no fun, you can tow the truck but what about the trailer?

Presumably GM will have some kind of lockable bed mount like they did for the Hummer. Only problem is when I need to use the bed, I‘ll probably look into the possibility of small spare stored under. There’s some possibilities of storing it on the trailer too.

 

[SilverDan]

Trailer good option but here's another option...hitch mount but has receiver for your trailer (max weight 7500 lbs). They've got other types of tire carriers as well.

I was planning that, but the trailer doesn't have much outside storage so I'm getting a 3rd party bumper storage tray/boxes which are really the treat, so the hitch isn't available. That would also cover up the license plate which might be a problem ... well so would putting a bike back there I suppose, but just not as much.

 

[SilverDan]

I would be thrilled to see Magnetic Ride Control but they haven't used it on a truck to date. It offers amazing capabilities...even Ferrari is using it.

DSSV has been the go to for trucks. Very capable but not adjustable until the ASV came out. Was hoping for ASV but MRC would do the trick.

Unfortunately, base Trail Boss ICE has only had the Rancho's. To get lockers and the DSSV shocks, you either had to order the ZR2/AT4X trims or, in 2025, ZR@/AT4X became options on Trail Boss/AT4 instead of separate trim levels.

Not a whisper on lockers in anything I've seen published for the 2026 SEV Trail Boss.

In addition to simplifying the physical architecture and master Ultium BOM I have zero doubt that the Marketing side isn't doing the same - they will definitely be mirroring the simplified structure on their side and we're already seeing it. Trims and options increase complexity and cost. I think we're already seeing it, they're using battery (Std, Ext, Max) and Trim (WT, LT, TR) as the main options, in addition to judicious use of upgrade packages for those who want an Extended battery but upgraded options. Otherwise the upgrades are determined by the Battery/Trim combination.

Point being, along with the slow roll on suspension information I'm now thinking we'll see something exciting. While they might offer a boutique option or two much later (like High Country), the 'option compression' we're already seeing appears to be pointing to physical lockers (well one locker and one e-locker) plus some kind of spicy shocks. *

Will be exciting in any case!

* Note we already had a boutique trim which was the RST and all it had was every option plus some window dressing. Then they dropped the RST and you have to go Denali to get the air bags. So any High Country or specialty TB I think will be similar, maybe some token hardware feature you don't need but mostly window dressing.

 

[SilverDan]

Why do you suggest one e-locker? Since they are going for reduced BOM complexity and so many of the drive components are common across the different vehicles, wouldn't they be both mechanical lockers? Also, how do you define e-locker?

Sorry using the wrong term, I'm thinking of a 'Virtual Locker' (it appears to be called) on the Hummer rear, using torque vectoring. But I'm not thinking this through, the Hummer has up to three motors with physical and virtual is my understanding. Maybe somebody can step in here who knows what they're talking about 😅

 

[SilverDan]

on the 3X with 3 Motors it's Virtual locker in the rear and Physical in the front, on the 2X it has 2 Physical lockers one for each of the single front and rear motors.

Checking the web - so the 3X has two motors on the rear which explains the virtual locking/torque vectoring, you're controlling each wheel individually. The front axle, with one motor needs a physical locker. So the SEV's would have one or two physical lockers only (probably two).

Anybody have a schematic of the motor and axle configuration for the SEV? I'm curious how the differential comes into play. Here's the Bolt from Webers vid

Final drive goes through motor center on top, differential at end, the two axles right/left to the front wheels.

In-situ

From the video the second 'idler gear' has a 'counter gear' on it. Not sure what that is there for, maybe some gear-head can explain

So presumably the Hummer has some locker Ultium motor variation - a standard Ultium motor version but with a locking differential. Given GM's new desire to reuse parts, presumably we have two of those in the SEV.

Having worked through this it seems pretty darn likely to me.

 

[SilverDan]

With separate motors for each wheel, e-lockers mean the wheel with traction is limited to the power of that wheel's motor and can even get less as the electronics try to match power to both wheels but are limited by the one with less traction.

Had to think about this for a bit, I think there’s a problem with that logic; it’s actually backwards. With one motor and two wheels on a flat surface, each wheel gets half the total power delivered. With a motor on each wheel, in total there’s twice the power. There’s always more power with more motors.

OK so other extreme is one wheel off the ground. It’s the same for single locked diff or dual motor - there’s only one operational motors with the total power in either case. Either the in air motor is off, or the diff only delivers to the traction wheel.

So you’re talking here about some middle ground where the two motors are trying to match power somehow? Like say there’s a side with slip, so it lowers the power output to that side to keep traction. Here the motors aren’t matched, they’re deliberately using different power levels to maintain traction.

So not seeing what the idea is here …

 

[SilverDan]

Hummer rear dual motor motor, duplicated ports for the two motors

Hummer/Silverado Front, Hummer version has a locking diff. Presumably the diff is built in like the housing? Looks like it would be on the left side output from this picture. If so then a variation.

Silverado back has a diff too, and will probably have a locker if it has any at all.

Now for the interesting question; what if the lockers are already built in but neutered? With low BOM lines like this it’s pretty common to just include dead hardware you neutered out for options, cheaper than having different variations. And would already be the case as the Hummer front uses the locker, with the non TB/AT4 SEV’s having them neutered 👀