Harsh downshift into 4th resolved (7G Tronic Plus)
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Joined: Apr 2003
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From: Northeast
2012 S350 Bluetec, 2014 GLK250 Bluetec, 2026 E350 4Matic
Harsh downshift into 4th resolved (7G Tronic Plus)
So, a very interesting side effect of my new engine mounts is that I no longer have a harsh downshift into 4th gear that used to happen when I floored it around 60 MPH to pass someone on the highway, for example. It jumps down from 7th into 4th and is now smooth every time. It used to SLAM into gear. I am guessing that the different alignment of the drivetrain and the weak engine mounts really play a big role in that sort of thing. I never expected something like that, what a sweet bonus! I wanted to share this with the community.
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From: V E G A S
1922 Ford Model T / no OBD
Did you had a chance to inspect old MM?
The cup-sized MM usually just collapse making for harder vibration, but I have seen older engines where MM would break and engine was lifting several inches when torque applied. That sure can make good slam.
Other observation is that gasoline engine drops 3 gears at high speed acceleration. My diesel never drops below 5 and most of the time it is single gear drop.
The cup-sized MM usually just collapse making for harder vibration, but I have seen older engines where MM would break and engine was lifting several inches when torque applied. That sure can make good slam.
Other observation is that gasoline engine drops 3 gears at high speed acceleration. My diesel never drops below 5 and most of the time it is single gear drop.
Thread Starter
MBWorld Fanatic!
Joined: Apr 2003
Posts: 1,036
Likes: 277
From: Northeast
2012 S350 Bluetec, 2014 GLK250 Bluetec, 2026 E350 4Matic
Did you had a chance to inspect old MM?
The cup-sized MM usually just collapse making for harder vibration, but I have seen older engines where MM would break and engine was lifting several inches when torque applied. That sure can make good slam.
Other observation is that gasoline engine drops 3 gears at high speed acceleration. My diesel never drops below 5 and most of the time it is single gear drop.
The cup-sized MM usually just collapse making for harder vibration, but I have seen older engines where MM would break and engine was lifting several inches when torque applied. That sure can make good slam.
Other observation is that gasoline engine drops 3 gears at high speed acceleration. My diesel never drops below 5 and most of the time it is single gear drop.
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2020 GLS450 (wife) / 2024 Ford Bronco (mine) / 2014 VW Tiquan (son)
Not surprising to me, as I learned on my past two Lexus vehicles that changing the motor mounts and transmission mount, is like resetting the architecture of the mechanicals back to new again. Totally tightens up the car. Since then, these are my go-to items to replace after about 5 years of age in general. I put them down as preventive maintenance for cars that I really enjoy and want to keep for a while.
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Joined: Aug 2016
Posts: 130
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'11 E350 4Matic Sport
I have my ‘11 scheduled for next Monday to have the engine and trans mounts done, 80k and they are beyond shot. Vibration has gotten so bad it will rattle some various heat shields when turning the steering wheel at idle and some decelerating downshifts will jolt the car. Have no had any hard accelerating downshifts to report.
Requested a GLC or GLE loaner to sport around in for the repair.
Cant wait to see what an E should really feel and sound like, the mounts were shot when I bought it (knew it going in and car was discounted to reflect the major repair). Like said above I imagine it’s gonna totally transform the car.
Requested a GLC or GLE loaner to sport around in for the repair.
Cant wait to see what an E should really feel and sound like, the mounts were shot when I bought it (knew it going in and car was discounted to reflect the major repair). Like said above I imagine it’s gonna totally transform the car.
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From: Cincinnati
2010 E350 4Matic
This gives me some hope because the shifts in my transmission have become more noticeable. Not bad but I feel a little push during the 4th to 5th upshift. I hope the mounts smooths that out.
