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16 Digital Steering Assist - How is yours?


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"new for 16" GM put Digital Steering Assist on the HD trucks.

 

Press release: http://www.gmc.com/gmc-life/trucks/five-advantages-of-2016-sierra-hd-digital-steering-assist-system.html

 

Mine, yuck.

 

Low speed is great. Lighter effort than my 12 HD.

 

Fine up to about 70MPH, above that and steering is super heavy.

 

Towing at ~73MPH, sometimes it's OK, most of the time it's like no power steering. Everything I've read says this should be the best thing ever. I didn't know it was a new feature when I ordered the truck.

 

If you have a 16, how does it for work for you at higher speeds, especially with T/H engaged? I think it's hard to notice the problem unless you are running on a curving expressway for longer periods of time.

 

I mainly see it on gradual turns (expressway of course). Especially if the road is flat, not banked and seems more so for left turns. If there is a gusty cross wind, where you need to make a lot of small intermittent corrections, it's really fatiguing (comparing to other trucks I've run, including the 2012 HD).

 

It may be getting a little better, or I may be getting more used to it, as we add miles (~8K currently). It seems to do it less now. On the return trip from the dealer last night I couldn't get it to act up on the sections of highway I was on (not in T/H mode).

 

According to this interview, the T/H mode will make steering heavier, which seems to hold true in some of my experience:

http://news.pickuptrucks.com/2015/10/what-you-need-to-know-about-gms-new-hd-steering-assist.html

 

PS - this truck has been in dealer for 21 days now for multiple issues. Definitely could be something wrong with the steering just on this truck, which is the reason for my post.

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I don't have much info on it so not really gonna help but I believe the reason for it getting harder at higher speeds and with tow haul enabled is to reduce sway, especially if you have a trailer hooked up to it. Keeps you from those sudden jerk reactions where the trailer will sway all over the road. I know both of my sister's VW's have steering very similar where the faster you go the less assist it provides in order to maintain control of the vehicle

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I really had no idea what that was until I read that link. But that explains the super light steering I've noticed at parking lot speeds, love it!

 

At highway speeds, I've noticed nothing you mention, mine is fine.

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Haven't towed yet but everything seems fine except I notice a little slop in the steering. Not much but enough to make me move the wheel a little back and forth. Unless it gets worse I will probably wait for my oil change to have them look at it.

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So I read this thread and I am confused - don't you want a "heavy" steering feel when towing? I would take that over a light, sloppy feel in a lighter truck.

 

I am asking because it's winter here and I have not towed my TT yet and I am not sure what to expect from these HD trucks.

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So I read this thread and I am confused - don't you want a "heavy" steering feel when towing? I would take that over a light, sloppy feel in a lighter truck.

 

I am asking because it's winter here and I have not towed my TT yet and I am not sure what to expect from these HD trucks.

 

Theory and description sounds great. In practice, on my truck, it's not when used over varying and real-world road conditions. Totally agree with others that the low-speed extra assist is excellent. I have no slop in the steering and it works well up to about 70.

 

What happens is at higher speeds, the steering is very difficult to turn, so you put in a lot of effort to make the small corrections when the trailer is being hit by the wind (or other things that you have to correct for when towing). Not like "half a turn OMG" but about the same movement you'd put in for a lane change or a bit more. This also applies to longer curves.

So if you only tow below 70 and either have all flat/straight roads and/or have no or constant winds, it will probably work generally great for you.

 

When summer hits and we switch to hauling the 5th wheel, we don't get over 70 so I won't have a problem then, I suspect.

 

On the way back from the dealer today (more on the heater issue) I popped on the expressway and tried to find an area where I can replicate the issue for them. I need to reiterate that I don't know if mine is expected behavior or a flaw. Since it works great at other speeds/conditions, I am leaning towards an error condition.

 

Set the cruise on 80 (mine is +1 high, so really "only" 79) and steering is heavier but not that unbearable. Click the T/H on and immediately I can feel a big difference.

 

Found a curve (NW to full W directional change) and it was very reproducable, very stiff, a lot of effort to make the curve. With three fingers holding the wheel at the bottom left, I had to use a very severe grip on the wheel (if you two-hand it, probably won't notice as much). If I let the wheel slip out of my fingers, instant return to center, snap to the right and truck jumps to straighten out (how is this a safety improvement, not sure).

 

So, on mine, with T/H and a trailer (enclosed snowmobile trailer) with the cruise set at 73/74 steering is very heavy, difficult to turn and fatiguing after a couple hour run. To the point I have to change hands or use both hands when making curves or if I'm fighting the wind.

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Theory and description sounds great. In practice, on my truck, it's not when used over varying and real-world road conditions. Totally agree with others that the low-speed extra assist is excellent. I have no slop in the steering and it works well up to about 70.

 

What happens is at higher speeds, the steering is very difficult to turn, so you put in a lot of effort to make the small corrections when the trailer is being hit by the wind (or other things that you have to correct for when towing). Not like "half a turn OMG" but about the same movement you'd put in for a lane change or a bit more. This also applies to longer curves.

So if you only tow below 70 and either have all flat/straight roads and/or have no or constant winds, it will probably work generally great for you.

 

When summer hits and we switch to hauling the 5th wheel, we don't get over 70 so I won't have a problem then, I suspect.

 

On the way back from the dealer today (more on the heater issue) I popped on the expressway and tried to find an area where I can replicate the issue for them. I need to reiterate that I don't know if mine is expected behavior or a flaw. Since it works great at other speeds/conditions, I am leaning towards an error condition.

 

Set the cruise on 80 (mine is +1 high, so really "only" 79) and steering is heavier but not that unbearable. Click the T/H on and immediately I can feel a big difference.

 

Found a curve (NW to full W directional change) and it was very reproducable, very stiff, a lot of effort to make the curve. With three fingers holding the wheel at the bottom left, I had to use a very severe grip on the wheel (if you two-hand it, probably won't notice as much). If I let the wheel slip out of my fingers, instant return to center, snap to the right and truck jumps to straighten out (how is this a safety improvement, not sure).

 

So, on mine, with T/H and a trailer (enclosed snowmobile trailer) with the cruise set at 73/74 steering is very heavy, difficult to turn and fatiguing after a couple hour run. To the point I have to change hands or use both hands when making curves or if I'm fighting the wind.

 

That is a great explanation, thanks. Definitely something I will have to experiment with and pay attention to for sure when towing.

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Thought I had brought it up here but couldn't find. Should have looked harder. Sorry for duplicate, though I do have "more information" now.

Don't be sorry, I posted the link to simply bring more info and feedback to the thread, I am here to learn as well.

 

 

 

 

 

I think this is a good system having said that I think the programming for the steering sucks and need updated. The Super Duty gets this same system for '17 and I bet it will be much smoother right out of the gate, hopefully GM has a update for this.

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So I read this thread and I am confused - don't you want a "heavy" steering feel when towing? I would take that over a light, sloppy feel in a lighter truck.

 

I am asking because it's winter here and I have not towed my TT yet and I am not sure what to expect from these HD trucks.

When pulling a trailer you have to do more steering as low speed turning you are swingong way out and quickly correcting to come back in, this requires a lot of assist, same at highway speeds, this is why tow/haul has more assist.

 

Again this is a great system but the programming sucks.

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When pulling a trailer you have to do more steering as low speed turning you are swingong way out and quickly correcting to come back in, this requires a lot of assist, same at highway speeds, this is why tow/haul has more assist.

 

Again this is a great system but the programming sucks.

I agree that you want more assist with T/H on.

 

According to that interview linked above to the pickuptruck.com article, GM is specifically decreasing assist when T/H is on at higher speeds. Their press release indicates more assist at low speed but doesn't say what's happening at higher speeds (the interview talks about it more):

 

 

on the highway when in Tow/Haul mode, the truck will actually take away some assist, making steering effort a little higher

Effort on mine is not "a little higher", mine is like almost no power assist.

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Did more testing with mine and also towed for about 1000 miles on a recent trip.

 

 

My truck is definitely worse with T/H engaged. I've resorted to disabling T/H if I'm traveling above 70 and towing. Not sure the ramifications to the powertrain of doing this.

 

I've found where mine really acts up is when you are turning into an unbanked turn or a negative bank (as in "the road is higher towards the inside of the turn").

 

For example, if the two lane road is high in the middle, when you cross into the left (to pass) and then have to turn slightly to the right to adjust the truck/trailer into that left lane, it will fight you hard - you are turning to the right and "uphill" once in the passing lane.

 

If the road is flat, not banked, and you turn either direction, it's very stiff.

 

If the road tips to the right and you are turning to the left, it's very stiff.

 

However, it's a dream if the road is banked and you are turning to the downside of that bank ("going with the flow").

 

Below 70, it's really not an issue and if the roads are properly laid out (banked so it's high on the outside of the turn) then it's awesome to drive and seems to drive itself.

 

I wonder if you could disable the higher speed functionality with a tuner? Of course, if mine is the only one doing this....

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  • 7 months later...

Okay, so I find this very interesting. I've put a little over 1000 miles on my new 2016 2500HD Duramax. The issue I am experiencing is excessive play in the steering only at highway speeds. I really can't come to the conclusion the issue is actually excessive play, but rather excessive power assist. At slower speeds the power steering feels about right. However, when I am driving highway speed, 55 to 70, it is very very easy to steer. It is so easy to the point that any small movement with my pinky finger on the wheel can send me off in the direction I turn the steering wheel. I am used to a heavy truck like feel that requires constant correction for wind and road conditions. So, to me, at highway speed the steering with this new digital assist feels kinda sloppy.

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