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No, no engine is normal to turn when clutch open. I suspect it thinks it's in neutral when it's actually (partly?) in a gear.
Another reason why I think you should always leave an SMG car in N. These SMG gearboxes do not have a parking pawl, so there’s no means of locking the transmission output shaft (which locks the driven axles). P just means it’s in a gear.

You should put a DCT in this one.
 

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Another reason why I think you should always leave an SMG car in N. These SMG gearboxes do not have a parking pawl, so there’s no means of locking the transmission output shaft (which locks the driven axles). P just means it’s in a gear.

You should put a DCT in this one.
Or get rid of all those electronic controlled transmission stuff and slap an E90 manual trans!
 

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Discussion Starter #185
Ladies, I just drained the smg gearbox lubricant to check for spare parts. Expected it to take a while and be a little stinky on account of having 80w90 in it. Instead it zipped right out and I'm nearly certain it's ATF. 😐

Any reason this thing would have ATF in it other than being previously improperly serviced?
 

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The bmw specified gear lube for my 2008 6-speed came out like water.
I put in a home brew of 0.75L Amsoil GL4 75w-80 that gives a 500,000 mile warranty on truck 18-speed gear boxes.
And about 1.0 L of Amsoil 5w-30 synchromesh.
I did not care about shift quality, I just wanted to protect gears from heavy track use.
Turns out trans is much easier to shift

will change soon and put in magnetic drain plug. Will try 100% 5w-30 synchromesh.

I would stick with bmw oil for 7-speed smg in your case.
The fast shifting of smg counts on a known friction coefficient for gear oil to allow synncros to complete their tasks in time window allowed by programs
 

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ATF has the proper viscosity for the smg. I've used MTF2 (pentosin / bmw fluid) and hated it. Switched to redline MTL which is a hair thicker and liked it better. Recently bought redline D4 ATF which has the right viscosity. Haven't tried it yet.

More details here:
 

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Discussion Starter #191
Commonly available, and in my experience Mobil lubricants are as good as anything.

Otherwise my bias is to Redline MTL, which is what I am holding in reserve for my other M5.
 

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Discussion Starter #193
Well, this sucker is at the shop getting the trans yanked.
Suffice to say, hope I find some delaminated wiring insulation on the shift position sensor harness once it's down out of the car!
 

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Discussion Starter #198
I'm not sure there was any. It sounded kind of like the gears were grinding....which would align with the shift forks position being wrong. There were no spare parts in the oil of either gearbox or engine.

If it does indeed have rod knock, only one thing to do....
 

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Discussion Starter #200
No it's the commie pinko eco rat bastards that thought they were being better 'global citizens' by spec-ing biodegradable wiring insulation as opposed to using something that it's specs met its use.

I have an opinion on this matter if it is not immediately obvious.

I suppose it is better than Subarus that use soy plastics and wiring that rats find delicious. Friend had an issue with this and was heckled accordingly.
 
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