What's with the lurch?

[V8BoatBuilder]

Can confirm, mine does not auto-disengage when the accelerator is pressed in a normal fashion, but I can feel the truck straining against it. I have not tried to really push it yet.

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[Stefan_the_vet]

So I got my Lightning a few days ago and already had two serious Incidences with it. First I crashed into my neighbors garage and the second time I knocked over an ElectrifyAmerica charger (that caused serious damage to the front of the car). Both accidents happened the same way. I brought the car to a stop, hitting the brake pedal and before I could shift it into park or reverse it suddenly lurched forward with huge acceleration. The first time I blamed myself, must have been my mistake. This is the first truck I own, was really excited about it. However after today I am worried something is not right with this truck. My insurance is probably wondering too, filing two claims within days. Thank god there were no people in my way, this would have killed them. Any insights?

 

[lightspeed]

Can confirm, mine does not auto-disengage when the accelerator is pressed in a normal fashion, but I can feel the truck straining against it. I have not tried to really push it yet.

The parking brake should automatically disengage when you give it some throttle.

 

[hturnerfamily]

The truck has a built-in 'park prawl' that keeps the truck's motors 'parked' when you put it into 'park', with no need for any additional 'emergency brake', under normal everyday circumstances. MUNROE has a video of this exact 'park prawl' device and how it works.
The emergency brake is a different thing, and is a mechanical means to 'lock down' the wheels to keep them from moving. It is controlling the wheels/brakes, NOT the motors. It can happen automatically when the truck's sensor see a certain amount of 'slope', with the red 'BRAKE ENGAGED' indicator on the driver screen.
It can also happen if you MANUALLY pull the Emergency Brake engagement handle, at the driver's left knee area, which is handy when you don't want the truck to have that addtional 'movement' after releasing the brake pedal, such as when hooking up to your camper, or just getting 'close' to a DC Fast Charger, etc. You can manually PUSH to disengage the brake when getting ready to go, OR if you press the 'GO' pedal hard and long enough, it will disengage AUTOMATICALLY, with a sometimes large 'lurch', as well.
You can imagine that the truck's designers wanted to have a substantial 'emergency brake' hold, and yet they also imagined that every driver might not want to have to reach down to disengage that brake hold everytime they are ready to go - I've done it plenty of times, when it caught me off guard, early on, when I didn't pay attention to the 'BRAKE ENGAGED' red indicator. I wondered why the truck seemed to 'not want to go' when I pressed the pedal, and then, suddenly, it lurched forward when it DID let go...

The truck also has a 'reverse brake' feature, which helps to brake the truck when you are in reverse and it senses something in the way, a safety feature, or as you are letting off the 'GO' pedal. BUT, this feature, if engaged, will also serve to create an issue if you are trying to back up to, and hook up to, a camper, or trailer, etc. It senses the vehicle and makes it very difficult for you to easily get close, or to come off the brake and expect the truck to move on it's own, without applying a lot of PRESSURE to the 'GO' pedal, which can then create a 'lurch', again, when that feature let's you override it's built-in safety mechanism. This caused me several times to almost run into my camper's hitch, until I realized that disabling this feature was best for me.

 

[dww]

When you are in one pedal driving and the truck is stopped, the last thing you expect is for it to roll forward when you shift to park. Why would you ever not want setting the electronic parking brake to be automatic. I’m trying to condition myself to set the parking brake first when I stop to park but I sometimes forget, with needing to park so close to superchargers or the front of your garage how did this ever pass QC? Especially when the truck does it correctly if you open the door while it’s in Drive?!

 

[TheBigBezo]

Reading through this is interesting. I have never experienced any of these issues so far. I routinely shift into park without using the physical brake and feel no movement unless I had some momentum. I only set the e brake on my driveway as it is sloped and didn't like the truck banging on the motor brake. I wonder if this issue is related to sloped driveways? I never experience the described motion in typical driving.

As for overriding the e brake, I noticed it early on and quickly found an appropriate feel for how much throttle was needed but since I use it so often (sloped driveway) releasing the handle is second nature to me.

 

[GarageMahal]

Having experienced this several times my alternate solution is to simply apply the brake again. This alleviates the back and forth bounce but I don't disagree with the setting the parking brake but haven't trained myself to do it yet. Note that this only happens to me when I park on a gentle slope.

 

[Maquis]

Lurch?

 

[3121]

Automatic ICE cars have the same play in the parking pawl. If you are on a slight incline and let off the brake the car will roll back or forward a couple inches. This is by design - there needs to be some play in the pawl and gear teeth otherwise it won’t disengage easily. The truck will automatically engage the parking brake if you are on a decent incline, otherwise the parking brake is not required.

Parking 101 from my high school driving instructor and auto shop teacher - This avoids the “lurch”
1) Come to a full stop, keep your foot on the brake pedal
2) Place vehicle in PARK and keep your foot on the brake pedal
3) Engage the Parking Brake and once engaged let your foot off the brake pedal

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