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      07-11-2010, 10:51 PM   #103
bobbydole
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Drives: 2007 BMW M Coupe
Join Date: Dec 2008
Location: Torrance, CA

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Second Encounter with 1st->2nd Grind

Today I was on the San Diego BMWCCA drive event and I want to report my 2nd experience with the 1st->2nd grind. We just completed our rest stop at Kit Carson Park in Escondido, CA. We were pulling out to make a left turn onto a busy street. So we had to carefully watch for an opening to merge in. When I saw my opportunity, I stepped on the gas in 1st gear and headed out to the center divider and then into the opening. I then quickly and completely depressed the clutch and pulled the stick from 1st to 2nd all the way back in one motion....."zzzzzzzzzzzztttttttttttt!" I don't know if this correctly describes the sound, but it's a loud high pitch metal grinding sound; just like the first time I encountered the 1st->2nd grind.

Right after it happened, it caught me off guard. So I pauseda second to evaluate exactly what I was doing. Foot is on the clutch all the way down; shifter won't go into 2nd gear and made a grinding sound.

This time I didn't pay too much attention to the RPM, but I bet it was high (above 5K but definitely below redline) since I was trying to merge into traffic. So here I am, I'm trying to merge and I have to slow down because I have to release and depress the clutch again to retry the shift.

In both times I encountered the 1st->2nd grind, I was pushing the car harder than I normally do. But (in my opinion) not beyond what should be within the car's capability. I wasn't even at redline! I almost never redline. Tried it a few times just for fun, but I never do it in regular driving.

At this point, I've read many suggestions to fix/avoid the 1st->2nd grind issue. Some say change shifting technique (push hard to the left and then down). I will try, but it seems to me that maybe this works for some because the technique slows the shift just enough to avoid the grind.

Some say shift slower. I can attest to this solution. When I shift slower in situations where I think I would have grind, I can feel the shift more notchy than usual. In other words, it's as if it "almost" won't go into 2nd gear, but since I'm shifting slowly, somehow it gives the gears a little more time to line up or something and then finally falls in.

The next thing I'm going to do is replace the tranny mounts like the others have tried and found some success. Hopefully this solves the problem. Now I just need to order the part and find a shop that will do the work for me.

Last edited by bobbydole; 07-11-2010 at 11:08 PM..
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