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Posted

Saw this warning in the owners manual for my 3500hd:

 


   { Warning
 Do not hold the brake pedal and press the accelerator pedal at the same time. Damage may occur to the power steering and power brake systems which could lead to reduced performance, up to and including loss of steering and brake assist.
 

 

Not that I do that when I drive, other than briefly on a steep hill start maybe, but does anyone know how the steering
system would be damaged by this?

 

Posted

I must have skipped over that part when I was looking through my manual, but it's really in there. If I were to hazard a guess, it's probably related to the variable steering on the higher level trims. Pressing the brake and throttle at the same time probably is a confusing thing for a system that trying to adjust based upon how you're driving.

Posted

Hummm, times have changed. The only thing back in the day that potentially wore out doing that in moderation  was the back tires. 

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Posted
12 hours ago, Another JR said:

Saw this warning in the owners manual for my 3500hd:

 


   { Warning
 Do not hold the brake pedal and press the accelerator pedal at the same time. Damage may occur to the power steering and power brake systems which could lead to reduced performance, up to and including loss of steering and brake assist.
 

 

Not that I do that when I drive, other than briefly on a steep hill start maybe, but does anyone know how the steering
system would be damaged by this?

 

 

 

 

Hydroboost.  Brake assist is provided via the power steering pump/hydraulic pressure.  It could be a scenario of over-pressurization of the booster or the ps pump and all of the hoses.  

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Posted

Same warning doesn't show up in the 2020 user manual, so I'm guessing it's a problem discovered before releasing the 2021's.

Posted

Thanks for bringing this up.  :cheers:

I use the brakes and throttle together off-road to load the suspension and get through difficult rocky situations with limited tire slip. 

Will need to look into this, as it's pretty important for me.  Funny the Dodge has hydroboost, but I've not had this issue, and I've run it through some pretty long rock stretches.  Will look into why it's an issue for the GM.  Maybe it will be simple, like adding an external cooler package (fingers crossed). 

Posted

I had a few funny thing happen when pulling out in my 21.  Mostly involving when I am sitting on a hill and I start on the gas pedal before I let off the brake,  the antilock brake system goes nuts and you hear the typical abs grinding noise as soon as the truck starts moving.  My truck also went nuts the one morning when I had to use the rumble strips for a bit because a tractor trailer wasn't paying too much attention to what he was doing.  The dash looked like a christmas tree with all the traction control and abs lights on and it wouldn't let me use cruise control until I shut the truck off.  I think GM puts the warning there to cover up their electrical gremlins.

  • 2 weeks later...
Posted

Hmmm. What would be the point of owning a truck then? That's a known tactic for gaining traction when on a boat ramp, an icy grade, stuck in mud, snow or sand. Im guessing my custom isn't an issue with this warning? I did get hun up in the sand once. Rocking the truck with wheels turned sharp got me into traction control errors and a service light. Fortunately after I got onto the road it reset itself after a short drive. Was worried I was gonna have to hit the dealer to clear a code 

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