downshift grinding problem...

schang · 07-24-2010, 12:11 AM

Hey guys, have any of you experienced a "grinding" problem when you downshift? This is with the STEPTRONIC in manual mode...

Today while I was slowing down for the exit ramp, I was going at about 75, braked and downshifted from 5th to 4th at about 3000 rpm and suddenly felt something grinding really LOUD under the hood(or near it). I've never had this problem before, could someone please shed some light? Could it be that the clutch was grinding? I'm totally freaking out right now. Only have about 450 miles atm.

GMT II · 07-24-2010, 12:44 AM

Welcome to the boards and congratulations on the car. Automatic transmissions do not have a clutch though. They utilize torque convertors instead and there are no gears inside those to grind. Also the transmission is located in a tunnel looking space behind the engine bay so a transmission sound would be coming from the underside of the car opposite the gear selector.

I don't know what that sound could be but I've driven BMW steps plenty and never heard such thing. I hope someone can id it for you though.

Dackelone · 07-24-2010, 05:34 AM

Maybe it was a belt squeal? Or an AC clutch issue? Did you have the AC on?

Well... hopefully it will happen more often and your dealer can figure out what is the problem. There shouldn't be any grinding though.

07-24-2010, 12:11 AM	#1
schang New Member 0 Rep 11 Posts Drives: 2010 135i Join Date: Jul 2010 Location: Seattle, WA iTrader: (0)	downshift grinding problem... Hey guys, have any of you experienced a "grinding" problem when you downshift? This is with the STEPTRONIC in manual mode... Today while I was slowing down for the exit ramp, I was going at about 75, braked and downshifted from 5th to 4th at about 3000 rpm and suddenly felt something grinding really LOUD under the hood(or near it). I've never had this problem before, could someone please shed some light? Could it be that the clutch was grinding? I'm totally freaking out right now. Only have about 450 miles atm. Last edited by schang; 07-24-2010 at 12:24 AM..
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07-24-2010, 12:44 AM	#2
GMT II Second Lieutenant 12 Rep 290 Posts Drives: I ride the bus. Join Date: Sep 2008 Location: NYC/Staten Isl. iTrader: (0)	Welcome to the boards and congratulations on the car. Automatic transmissions do not have a clutch though. They utilize torque convertors instead and there are no gears inside those to grind. Also the transmission is located in a tunnel looking space behind the engine bay so a transmission sound would be coming from the underside of the car opposite the gear selector. I don't know what that sound could be but I've driven BMW steps plenty and never heard such thing. I hope someone can id it for you though. __________________ 2009 135i Coupe Sedona Red/Beige Boston Leather 6MT / ZPP / ZSP / Nav / Prem. Hi-Fi / Sirius / CA / Heated Seats (you keep the ski bag) / Park Dist. / HD Radio (because it was free)
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07-24-2010, 05:34 AM	#3
Dackelone European Editor 10589 Rep 22,992 Posts Drives: N54 e82 Join Date: Feb 2010 Location: Bayern, Germany iTrader: (1)	Maybe it was a belt squeal? Or an AC clutch issue? Did you have the AC on? Well... hopefully it will happen more often and your dealer can figure out what is the problem. There shouldn't be any grinding though.
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