Direct steering, variable ratio steering
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MBWorld Fanatic!
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2019 E300
Direct steering, variable ratio steering
Does the W213 have Direct steering or variable ratio steering? I find myself over steering the E300 into corners and difficulty holding a line on long sweeping turns at speed. The increase steering ratio at increase steering angle could cause those issues. Perhaps it might take me a while to get use to it, anybody else having to deal with.this learning curve?
Out Of Control!!
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From: San Francisco Bay Area
2019 C63CS
It's hard to find detailed information on the Mercedes steering, but I believe they are variable ratio based on steering angle, which is how it feels to me. The larger the steering angle the more direct the steering becomes. As opposed to some other variable ratio steering systems, though, the ratio doesn't change based on speed. But basically the more you turn in, the less you have to turn the steering wheel for an incremental change in steering angle. So this could be what you are feeling. Basically in a shallow curve you have to turn the steering wheel proportionally more than in a sharp curve. It's indirect for minor turns to increase straight line stability, but becomes more direct the sharper the turn. It works quite well in my AMG at least. My previous Audi RS5 had a variable ratio based on speed, which at times could be odd, but to compensate for it when driving spirited with frequently changing speeds, the sportiest setting reverted to a direct ratio, so it offered the best of both. It was easy to maneuver in daily driving and in parking lots, but on a winding road I could just select the fixed ratio. The AMG steering at least negates the need for a fixed ratio. It seems to blend daily driving maneuverability with a sporty direct steering, and I haven't felt an issue in non-AMG models when I had them as loaners.
Here's what I found at least for the AMG steering, and it confirms what I said.
https://www.mbusa.com/en/amg/perform...nical-steering
Here's what I found at least for the AMG steering, and it confirms what I said.
https://www.mbusa.com/en/amg/perform...nical-steering
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2019 E300
Superswiss, as always, you are a fountain of information. According to the following website, the 2019 E300 is suppose to have direct steering, variable steering ratio based on the steering angle and also speed sensitive power steering assist. Like most variable steering, it takes a while to get use to. The Mercedes’ variable steering seems a bit more predicable than the BMW’s active steering which is speed sensitive.
Power That Moves You
Under the hood of the 2019 E 300, you’ll find a 2.0L turbo 4-cylinder engine that generates 241 hp and 273 lb-ft of torque. The E 300 also comes with a 9G-TRONIC® automatic transmission and DYNAMIC SELECT®. This program lets you further customize driving by modifying and altering shift points, as well as steering effort. All of that power isn’t at the expense of efficiency either, as the 2019 E 300 earns an EPA-estimated 21 mpg city and 30 mpg highway. Other performance highlights include:- ECO-START®/Stop system
- 4-wheel multilink suspension
- ESP® Dynamic Cornering Assist
- Electromechanical power steering with Direct-steer
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2019 E300
Just check out my E300’s steering column, lock to lock is about 2 1/4 turn. From center, its about 1 1/8 turn to either side, that is a pretty aggressive steering ratio. Usually, its about 2.5 to 3 turns lock to lock.
Out Of Control!!
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2017 GLE350 4MATIC
Two things are at work: geometry and assist.
Geometry (ratio) is variable by virtue of the way gear teeth are cut into the steering rack. It’s a “fixed and variable” ratio. There is no software or electronics involved with this.
Assist in the old days was made variable based on hydraulic system design that took vehicle speed and steering torque into account. Now it’s done electrically. Assist torque can be whatever, whenever, up to the limit of the assist electric motor, based on software and sensors. It is much more easily tuned by the carmaker.
Geometry (ratio) is variable by virtue of the way gear teeth are cut into the steering rack. It’s a “fixed and variable” ratio. There is no software or electronics involved with this.
Assist in the old days was made variable based on hydraulic system design that took vehicle speed and steering torque into account. Now it’s done electrically. Assist torque can be whatever, whenever, up to the limit of the assist electric motor, based on software and sensors. It is much more easily tuned by the carmaker.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2015
Posts: 1,583
Likes: 293
2019 E300
Two things are at work: geometry and assist.
Geometry (ratio) is variable by virtue of the way gear teeth are cut into the steering rack. It’s a “fixed and variable” ratio. There is no software or electronics involved with this.
Assist in the old days was made variable based on hydraulic system design that took vehicle speed and steering torque into account. Now it’s done electrically. Assist torque can be whatever, whenever, up to the limit of the assist electric motor, based on software and sensors. It is much more easily tuned by the carmaker.
Geometry (ratio) is variable by virtue of the way gear teeth are cut into the steering rack. It’s a “fixed and variable” ratio. There is no software or electronics involved with this.
Assist in the old days was made variable based on hydraulic system design that took vehicle speed and steering torque into account. Now it’s done electrically. Assist torque can be whatever, whenever, up to the limit of the assist electric motor, based on software and sensors. It is much more easily tuned by the carmaker.
Last edited by The G Man; Feb 8, 2022 at 04:00 PM.
