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Rough downshift?

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Old 05-24-2006, 07:47 AM
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CLS 500
Rough downshift?

I have a new 2006, CLS500, with 1000 miles. As the car decelerates to a stop under light braking, I feel a "clunk" as the tranny downshifts to either 1st or 2nd (S or C) right before the stop. Can I expect this to smooth out as the transmission gets broken in or should my 7G tranny be silky smooth downshifting normally when stopping which would indicate I need an adjustment?
Old 05-24-2006, 11:28 AM
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RJC
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Do a main forum search under 7 speed or 7G, there is lots of talk about this issue.
Old 05-25-2006, 09:50 PM
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2000 ML 320, 2003 CBR600F4i, 99 Eclipse GSX
Take it to the dealer, depending on the severity it will be one of two problems. If its not horribly harsh, it probably needs a software flash and possibly a valvebody. If it is extremely harsh, it will need to be removed to reinstall a circlip that holds a clutch pack tolerance in check.
Old 05-25-2006, 11:05 PM
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When I took my car in for service (2005 E500.. 6k miles) I listed the same exact thing.
Tech said "Normal".
How can that sort of shifting be Normal?
I calibrate engine and trans software for a living.. I know how a car should shift.
Actually.. I listed quite a few issues.
All were "Normal"
Pisses me off.

Some of the things they didn't even check.
Like the seat belt warning for the passenger seats goes off by itself when nobody (or anything) is in the seat.

Tech said my shake in the steering wheel at around 60 MPH was due to the tires getting flat spots from sitting. Well these Pilots must be pieces of crap if they flat spot in 1 day. I can let any of my other vehicles sit for weeks and they are smooth.

Is the tech at my local dealership a lazy clown?

The only thing they actually did to my car out of 10 things was rotate the tires.
But they never even checked the air pressure.

Makes me mad.
Old 05-26-2006, 09:27 AM
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C32 AMG
Originally Posted by RunninRS
When I took my car in for service (2005 E500.. 6k miles) I listed the same exact thing.
Tech said "Normal".
How can that sort of shifting be Normal?
I calibrate engine and trans software for a living.. I know how a car should shift.
Actually.. I listed quite a few issues.
All were "Normal"
Pisses me off.

Some of the things they didn't even check.
Like the seat belt warning for the passenger seats goes off by itself when nobody (or anything) is in the seat.

Tech said my shake in the steering wheel at around 60 MPH was due to the tires getting flat spots from sitting. Well these Pilots must be pieces of crap if they flat spot in 1 day. I can let any of my other vehicles sit for weeks and they are smooth.

Is the tech at my local dealership a lazy clown?

The only thing they actually did to my car out of 10 things was rotate the tires.
But they never even checked the air pressure.

Makes me mad.

Flatspotting on street tires is a condition that should go away as the tires warm up. Basically, the tires get "stuck" in the position you parked them, and the various belts and cords need to loosen up so that the tire becomes round again. So the technican may be right, but if the problem persists more than 5 or 10 minutes, he's wrong.
Old 05-26-2006, 10:54 AM
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So should I have MB replace all my tires with ones that don't do this?
I drive 6 other vehicles.. NONE show this 'problem' but none of them have Michelin Pilot Primacy's on them (they suck in the rain too).
If the E500 sits for a day (or more.. or less).. it shakes.
It has 6500 miles on it now.

My 04 Z06, 00 F350, 2 V8 Jeep Grand Cherokees, 05 Mustang and 06 STS can sit as long as I want and all don't exibit tire flat spotting. I must admit, kinda hard to tell on the F350
Real sad a $60K car sits for a day and then the steering wheel visibly shakes.
It's embarassing when people are with me.
Old 06-24-2006, 07:21 AM
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E240 03
Reflashing the ECU software

if the problem is occuring in the parking lot or when curving, then check if the jerking occurs when the car changes gear when the RPM is less than 1700. If this is the case and the problem is recurring then u need to reflash the ECU and sometimes change it. First try to reset the key by pressing the openning button on your remote till all the windows are down then close them back with your remote, if the problem is gone for one day then u need to take it to the dealer to reinstall the ECU software.

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