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Recently, I noticed that my car slid backward down the driveway overnight. I've always put in first gear when I park w/o the parking brakes on (I do it now every time since I began noticing it). So I thought I give it a test. I came home one day, put the tranny in first gear and shut off the engine. My car started sliding backward. My driveway is on an incline. Is it my clutch that is giving out? I don't have a problem with pick up when I'm driving. Does anyone know what might be causing this?:cheers:

Vinny
 

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Maybe check your "transmission" fluid?

Check your brake fluid, as with a 540i your brake fluid is also the hydraulic fluid for your clutch. I'd think if it was slipping like that while you were driving, you'd know about it. Of course, if you were leaking that, I suppose your question would be "why is it so hard to shift gears?" or "why is my clutch pedal resting on the floor?" but it is something worth checking.

I have a 2000 540i and right after I bought it I had a hard time shifting and actually blamed it on the new winter boots I bought -- I thought I just couldn't get the clutch to let go as my boot must have been stuck on something. By the time I got home I was running stop signs as I knew if I came out of gear I was never going to get back in. I suspected the clutch slave cylinder was leaking. Before tearing things all apart I inspected the pedal and noticed it was almost on the floor. I simply lifted it up with two fingers and it stayed up and I drove it around nervously for an hour waiting to see the problem come back. Then I drove it sorta nervously for another six months. At this point it's been about a year and it hasn't returned, at all. I suspect I had a bit of grit caught somewhere and lifting the pedal up must have moved the fluid around and whatever was stuck now isn't. I wonder if you're in a similar situation where the clutch is not engaging for some reason, especially if the car is off and the lines aren't pressurized.

If your brake fluid is low, or too high (installed new brake pads after adding brake fluid during an oil change or whatever) I can think of a couple unusual things that might happen. I myself am due for new brake pads and I'm going to flush the fluid while I'm at it which I suspect I should have done at the time but had no idea that the brake fluid had anything to do with the transmission at the time.

Happy hunting!

-tc
 

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What let your Trans. Hold your car when you have an e-brake designed just for that? I don't understand why most people don't use their e-brake.
 

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I've been regularly driving manual transmission cars since 1990 and I've always left my cars in 1st gear and used the e-brake to prevent the car from rolling. I'd guess there are multiple factors to cause the vehicle to roll despite being in gear, not just one definitive one. There are several threads on the internet discussing this specific topic.


Google this and decide: Manual transmission car in 1st gear but still rolls backwards.
 

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If it's steep enough it will eventually roll in first gear. If you think of your engine as a giant air pump (which is basically what it is), it's bound to have a very slow leak down. Once that compression slowly leaks down enough over hours, it can definitely turn one rotation with enough force on it, then many hours later, another rotation, and by morning your car isn't where you left it! Get that e-brake fixed!
 

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Yes please just use the parking brake, just using the transmission makes no sense. Leave it in gear for INSURANCE, nothing else.

I have a friend that does something just as silly if you ask me, he pulls the handbrake up enough to just barely prevent the car from rolling, then leaves it in gear for insurance, so that he does not stretch the ebrake cable. However, if the wind blows too high, the car ends up rolling a little and adding the strain to the drivetrain since that's what's holding it now.

What you all fail to realize, is that instead of pulling on and using the hand brake for what it's designed to do, you are putting strain not only on the motor mounts, transmission mounts, guibo, and diff mounts, but you are also holding the DMF springs under extra tension, which will eventually weaken them faster too.

Does wearing all those things out to save an ebrake cable sound smart to anyone here?

Chris
 

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Also it's better not to turn the engine backwards which is what's happening when the car is rolling backwards in first. Reverse has a higher ratio than first so actually has better holding power and would be doubly good in this scenario given the incline and direction in which the car is sitting.
 
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