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Yes, the left lane on the highway, parking lot sloped for drainage, high speed, low speed. It is similar to when a brake drags on one wheel but not as defined as that. If I let go and coast to a stop it's pretty dramatic. They took it out for another test drive but I never heard back before they closed. Lots of quick take offs, like they suspect torque steer.
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That's definitely strange. I suppose if something was "off" in the differential, it could cause one wheel to pull harder than the other (consistently, under power). But if that were the case, I would expect the car to pull one direction when under power and the opposite direction while under regen. You certainly seem to be experiencing something different than how my 2019 behaves. It tracks straight in parking lots, particularly at lower speeds.

Mike
 

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My problem still exists after them changing the steering gearbox. For the past 2 months they've been dicking around. They say they want to compare it to another Bolt to confirm if this drift to the right is normal (steering not returning 100% to dead center, maybe only 96% or so of the way back). The problem is unlike in the US where you have 10+ cars on every dealers lot. Most dealer never have a single one for months on end. I'm still pushing them and will keep you all posted as I make progress.
FYI. These dumb dumbs, acknowledge there is a drift to the right...But trying to figure out if it's normal??? Last time I checked no car ever drifted right as part of it's "normal" engineered design and operation.
 

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Well if it's any help, I can tell you that my 2019 does not behave like yours. I reread all your posts to be sure. At first, I thought mine had a problem with drifting to the right in general but in my case, it is 100% related to road crown. If the road crowns down on the right side, it pulls right. If it crowns down on the left side, it pulls left instead. And I've tested mine a dozen or so times now both in parking lots and on the road to test return-to-center. Mine behaves as you would expect. That is, if you make a left turn and then let go, the wheel returns almost to center but has a slight bias to the direction you were going: turn left and release and it returns almost to center but with a slight left bias... turn right and let go and it returns to almost center but with a hint of right bias. This is what you would expect since what your car is doing in this situation is wanting to take a tangential line to the curve and once you get very close to centered, there is almost no angular force left to force it back completely straight. Even in theory, it should never return to 100% center because the force making it return to center reduces to zero by 100%... and there is nothing "inherent" in any car's steering that makes it want to drive straight other than the external (turning) forces being applied to the car.

So I'm not a dealer testing cars on a lot, but it sounds like yours is not behaving like mine. Yours appears to return to center after a left turn but turn right after a right turn. That's definitely not what mine does! Mine won't return quite exactly to center after either left/right turns (I'd say the wheel is maybe half a degree from center) but at least it's symmetrical on both left and right turns and doesn't favor right.

Mike
 

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Discussion Starter #45
My car is at the dealership again to troubleshoot this issue. They are working with GM. Does anyone have any information to add?
 

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Mine eventually settled in. I have about 6400 miles now. I have to wonder if the tires had something to do with it. We'll find out if I rotate them like I should.
 

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Hi all. Been a while since I was last on but will give you an update. This pulling/drifting to the right at low speeds while coming out of a right turn is now deemed "NORMAL" by GM. My service manager got word from corporate on the open case that this is now considered normal. I personally even test drove a new 2020 on the lot and it performed the same way drifting slightly right at low speeds while coming out of a right hand turn (like the wheel only returns 95% back to the center position). However; The dealer told me they have left this case open which indicates that although this is normal GM recognizes it as a issue and may continue to work on a solution. Like maybe a software change that somehow forces the steering column to move that last 5% back to center on it's own or something.
My thoughts are that unlike a gas car which has the weight of an engine overtop the axle of the front wheels there is enough friction to force those wheels straight. An EV on the other hand has less weight in this position and instead the battery pack evenly distributes the weight further back. Additionally it makes sense because once you accumulate some speed lets say around 40-60km or so and also highway speeds you now have enough friction and momentum to push the wheels straight again and the car cruises fine.
 

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My thoughts are that unlike a gas car which has the weight of an engine overtop the axle of the front wheels there is enough friction to force those wheels straight. An EV on the other hand has less weight in this position and instead the battery pack evenly distributes the weight further back. Additionally it makes sense because once you accumulate some speed lets say around 40-60km or so and also highway speeds you now have enough friction and momentum to push the wheels straight again and the car cruises fine.
I am very sorry that they haven't actually addressed the problem. I am not an auto engineer. But as somebody who wasted his youth obsessing over this stuff, weight distribution effects lots of stuff, but does not prevent the wheels from recentering. Even though the tail heavy VW beetle wanted to swap ends, the front wheels would point straight ahead, if properly aligned.

In addition to mechanical alignment, on modern cars with electric power assist, the artificial centering action must also work correctly. I very deliberately avoided getting the lane keep assist package, because these things add an additional source of problems. Remember...every solution creates two new problems. Our stripped LT tracks arrow straight.
 

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It is incredibly frustrating that GM has ongoing problems with power steering, power brakes, and even suspension. If they can't get this simple technology sorted out, what makes folks believe they will ever being riding in self-driving cars?
 

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I still suspect it is possible that the alignment in the Bolt is set to reduce rolling friction and improve range and that can cause some differences in steering and tracking. Caster and weight distribution can be a factor and if they use less toe (to reduce friction) than most vehicles, that can have an effect too. I was not able to find Bolt alignment specs online: they all seem to be hidden by a "pay me first" methodology.

Mike
 

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I still suspect it is possible that the alignment in the Bolt is set to reduce rolling friction and improve range and that can cause some differences in steering and tracking. Caster and weight distribution can be a factor and if they use less toe (to reduce friction) than most vehicles, that can have an effect too. I was not able to find Bolt alignment specs online: they all seem to be hidden by a "pay me first" methodology.

Mike
Wouldn't be at all surprised if they have less toe-in. Typical trick used by hypermilers. Still...something is wrong with the Bolts not returning to center. Our Bolt still drives perfectly after 31K miles. Fingers crossed.
 

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Wouldn't be at all surprised if they have less toe-in. Typical trick used by hypermilers. Still...something is wrong with the Bolts not returning to center. Our Bolt still drives perfectly after 31K miles. Fingers crossed.
Wonder what the caster spec is for the Bolt? Would think it would provide some self-centering too.
 

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There are multiple factors that return the steering to center. There's caster which tends to return steering to center when the suspension is "pushed down" as it is from the weight of the car. There's also the tendency of an object to travel in a straight line unless a force is applied: when turning, if you let go of the steering wheel, the car will try to take a tangential course in a straight line from the circle you were turning. The latter is just physics but it's a big part of returning to center, so the slower you are going and the closer your wheel is to already being centered, the less it will have a tendency to straighten out. All this is just a fancy way of saying that the slower you are going, the less tendency the wheel will have to returning to center. On any car, if you are going very slow, the steering wheel will not return to full center if you let it go (it'll have some bias in the original turning direction). It could be that the Bolt's tendency to return to full center is just at a higher speed than most cars... again due to alignment, suspension dynamics, steering components, etc.

With all that said, I would think it would have the same tendency at the same speed on level ground when going left vs right. It shouldn't have less of a tendency to return to center after a right turn for example, compared to a left turn.

Mike
 

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With all that said, I would think it would have the same tendency at the same speed on level ground when going left vs right. It shouldn't have less of a tendency to return to center after a right turn for example, compared to a left turn.
Exactly!
 

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shouldn't have less of a tendency to return to center after a right turn for example, compared to a left turn.
well maybe if one considers the direction of travel in the northern hemisphere where north/south travel results in a Coriolis effect. just do ones testing going east/west.
 
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