Offroad performance similar to a Humvee?

[AquaMan]

If Tesla had an opposite, it would be Hummer, a company that's no longer in business.

I'm sure there are a few Hummer-haters in these forums, but one thing you can't deny: The original (first generation) H1 or military-spec Humvee had insane performance in terms of navigating offroad. It was literally capable of climbing a 30" cliff, as the Pentagon had originally requested.

One of its advantages was that the rear differential and engine were both elevated, so it could "straddle over" fairly large boulders, with two wheels on each side. Even the most "lifted" vehicles don't have that feature.

But the Cybertruck just might have similar clearance in the center, and a low center of gravity to boot, even lower than the Hummers.

So I'm thinking maybe the Cybertruck may be able to go where even the original Hummer could not. This is pure conjecture, but whadya think folks? If so, Tesla should highlight that fact, it may get some serious respect.

 

[billarnett]

I don’t think it will come anywhere near the H1 for serious rock crawling. It will be fine for the easy stuff. Might even manage the Rubicon Trail with an expert driver. But the approach and departure angles are not even as good as a stock Jeep Wrangler let alone an H1. And we don’t know how strong it is underneath; will it stand up to the kind of punishment that a rock crawler inevitably suffers? What about deep water fording? And we don’t know about the tires. It looks like there’s some extra room under the fenders but it’s hard to tell how much. Can I fit a set of 37x13.5 mud terrains? If not, it isn’t going to keep up with my Jeep on the rocks. And where’s the spare? Can I mount a winch somewhere and is there enough 12v power for it? Are the bumpers strong enough to take some punishment? Lots of questions. I don’t expect quick answers. I’m hoping that as the design matures that some of these issues can be addressed. As AquaMan implied, Tesla has the potential here to have a real winner here.

 

[Zybane]

The Achilles heel of this Cybertruck is the break-over angle. I hope there aren't any complications when I go to put larger tires on mine.

 

[billarnett]

The Achilles heel of this Cybertruck is the break-over angle. I hope there aren't any complications when I go to put larger tires on mine.

Agreed. Though the approach and departure angles aren't that great, either. Anyone have any idea how big the tires on the demo truck were? I looks to me like it might be possible to put slightly bigger tires on but not much. This is probably the biggest single thing that will make or break the Cybertrk as an off-roader.

 

[billarnett]

... Anyone have any idea how big the tires on the demo truck were? I looks to me like it might be possible to put slightly bigger tires on but not much. This is probably the biggest single thing that will make or break the Cybertrk as an off-roader.

The MotorTrend site claims they're 35s. If that's right it's probably possible to go up to 37s. That would be pretty good!

https://www.motortrend.com/cars/tesla/cybertruck/2021/tesla-cybertruck-electric-pickup-photos-info

It also claims that there's some sort of underneath protection. That's critical for rock crawling. I sure would like to see a demo of the CyberTruck hitting some big rocks.

 

[Saghost]

Well, It's narrower than the H1, so it'll certainly be able to go where the H1 can't.

(But seriously, the width has been one of the largest limitations of the H1 offroad from what I've read - a lot of trails have trees that typical offroading cars easily fit among but H1s struggle.)

Of course, being narrower with that ground clearance means it probably can't handle as much of a side slope - at least with the suspension in the high position (lower CG helps, but it can't be that much lower.)

Being able to dynamically adapt the suspension to the trail is certainly a strength - if the car and/or driver know when and how to adjust it to best advantage.

For best results, they really need some sort of locking or limited slip front differential - or a four motor version. I'm sure it'll have the same brake based limited slip the other Tesla's have, but that'll never be as good as a proper differential. The Tri-motor version has the rear handled, of course, with each wheel able to deliver whatever torque is needed.

It seems like it'll be pretty far up on the list as stock 4x4s go for off road ability, but I'm not sure it'll keep up with a good modded one yet.

 

[AquaMan]

Well, It's narrower than the H1, so it'll certainly be able to go where the H1 can't.

Ah, like the McDonald's drive thu?

 

[billarnett]

...Of course, being narrower with that ground clearance means it probably can't handle as much of a side slope - at least with the suspension in the high position (lower CG helps, but it can't be that much lower.) ...

Well, an H1 was pretty good in that respect. If the Cybertruck is anywhere close it will be great. I've had my lifted Wrangler on a side slope at an angle of 25 degrees and let me tell you that's really terrifying. I'm sure the Cybertruck will be able to do considerably better than that. I'm also sure I don't want to test it

(There's a spot near Moab UT called Hummer Hill. My Jeep said that slope was 35 degrees when I went up it. Rumor has it that an H1 could park on that slope sideways! Let's see the Cybertruck try that

Here's hoping there's a pitch/roll display option on the big screen (like the new Jeeps) with markings at the maximum possible angles.

 

[Reeler]

A two-door jeep-configuration version that was not so long would be great. The low center of gravity will allow it to climb very steep stuff. I would worry about a boulder penetrating the batteries.

 

[billarnett]

Motor Trend says there's no hope of a 2-door version. There are pluses and minuses to a long wheelbase. But what really matters is the breakover angle. No specs given but it doesn't look good. Maybe bigger tires could help but not much I'm afraid.

 

[jboy210]

Well, an H1 was pretty good in that respect. If the Cybertruck is anywhere close it will be great. I've had my lifted Wrangler on a side slope at an angle of 25 degrees and let me tell you that's really terrifying. I'm sure the Cybertruck will be able to do considerably better than that. I'm also sure I don't want to test it

(There's a spot near Moab UT called Hummer Hill. My Jeep said that slope was 35 degrees when I went up it. Rumor has it that an H1 could park on that slope sideways! Let's see the Cybertruck try that

Here's hoping there's a pitch/roll display option on the big screen (like the new Jeeps) with markings at the maximum possible angles.

Cybertuck should do much better than a jeep in rollover resistance. The center of gravity is much lower with the heavy batteries below your feet. The Model X is almost impossible to rollover.

 

[$TRONG]

Did someone say approach angle?

 

[keeney]

… I would worry about a boulder penetrating the batteries.

Is the bottom cover comprised of 3mm-thick hard stainless? I doubt the entire bottom (apx. 240 sq-ft) is that thick from the factory because it would weigh like 1300 lbs. Maybe just the areas where the batteries are is covered with thicker protection?

It would be easy enough to add some protection down there since its nice and flat, but you would still be adding 100's of lbs to the truck.

The batteries are designed to sustain collisions and not short-out and burn the vehicle to the ground, but they could still get damaged to the point where you are shut down and stuck.

 

[keeney]

...Can I mount a winch somewhere and is there enough 12v power for it?

That Frunk could hold a giant winch tucked away out of the elements and without destroying the aerodynamics. In the photos of the exoskeleton, the frunk floor and sides appear to be fairly integral to the structure of the front of the truck and could serve as a basis for mounting.

In regards to 12v power - with the advent of EV trucks, it would be super awesome if accessories like winches (and snow plow hydraulics, etc.) could be purpose-built to tap into the full power of the main battery bank and use motors and motor controllers with higher voltages. I would encourage Tesla, Rivian, and Bollinger to get together to promulgate a standardized way to have accessories tap into main battery power.

 

[GoMobileTires]

i cant wait to see the cyber truck do some off roading!!

 

[DarthPierce]

That Frunk could hold a giant winch tucked away out of the elements and without destroying the aerodynamics. In the photos of the exoskeleton, the frunk floor and sides appear to be fairly integral to the structure of the front of the truck and could serve as a basis for mounting.

In regards to 12v power - with the advent of EV trucks, it would be super awesome if accessories like winches (and snow plow hydraulics, etc.) could be purpose-built to tap into the full power of the main battery bank and use motors and motor controllers with higher voltages. I would encourage Tesla, Rivian, and Bollinger to get together to promulgate a standardized way to have accessories tap into main battery power.

You don't need a 400V winch. The point of a winch is it's geared way down to have a ton of torque with very little power.

Yes, you could have a faster winch running off 400V, but you'd also have a winch that has literally lethal voltages running through it. (Not fun to be electrocuted by your winch because you're standing in mud while turning it on)

 

[keeney]

You don't need a 400V winch.

Small ATV winches easily draw 50 to 80 amps at 12v. Larger winches can suck down 100's of amps at max pull. Unless you have a somewhat larger 12v battery, you are going to run out of winching power pretty quick trying to get a 6500lb vehicle unstuck.

My point being that for serious winching, it needs to draw power from the main batteries and be able to do so at full pulling current.

There are lots of 24v winches available, so maybe the right electrical design would be a step-down inverter from 400v to 24v.
​

 

[Saghost]

Small ATV winches easily draw 50 to 80 amps at 12v. Larger winches can suck down 100's of amps at max pull. Unless you have a somewhat larger 12v battery, you are going to run out of winching power pretty quick trying to get a 6500lb vehicle unstuck.

My point being that for serious winching, it needs to draw power from the main batteries and be able to do so at full pulling current.

There are lots of 24v winches available, so maybe the right electrical design would be a step-down inverter from 400v to 24v.
​

You make a good point. His point that lethal 400V requires expensive special handling is also well taken.

As you suggest at the end, a higher still mostly safe voltage is likely the best answer.

The automotive industry has been trying to get a ~40V standard rolling for a while now, for the belt alternator starter systems. That would be a logical choice if you didn’t use the established 24V options - rules for DC start becoming more limiting above 48V.

 

[KBowden]

I was figuring if you mount a winch up front you would need to install a 12v battery and charge controller in the frunk to supply the power for the winch,

 

[coleAK]

I don’t think it will come anywhere near the H1 for serious rock crawling. It will be fine for the easy stuff. Might even manage the Rubicon Trail with an expert driver. But the approach and departure angles are not even as good as a stock Jeep Wrangler let alone an H1. And we don’t know how strong it is underneath; will it stand up to the kind of punishment that a rock crawler inevitably suffers? What about deep water fording? And we don’t know about the tires. It looks like there’s some extra room under the fenders but it’s hard to tell how much. Can I fit a set of 37x13.5 mud terrains? If not, it isn’t going to keep up with my Jeep on the rocks. And where’s the spare? Can I mount a winch somewhere and is there enough 12v power for it? Are the bumpers strong enough to take some punishment? Lots of questions. I don’t expect quick answers. I’m hoping that as the design matures that some of these issues can be addressed. As AquaMan implied, Tesla has the potential here to have a real winner here.

I’ve done the Rubicon in a FJ40. No way the entire trial would be possible in a CT, it’s too large. There are no confirmed reports of a 200 series LC doing it and the CT will be longer and wider than a 200. Also my big concern Off roading is under carriage penetration (battery), sliders?, and the “exoskeleton” (unibody) ability to handle hard rock impacts and the major torsion encountered.