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Discussion Starter · #1 ·
Who can tell me if an E60 M5 with SMG3 transmission can or cannot be over-reved? I know that there is a rev-limiter on accelleration
and that when requesting a downshift with the revs close to the redline, the SMG will not allow the downshift and the gear number will
flash to prevent the over-rev. Is this correct?????

Does anybody have any knowledge about the FAstfa secret code that is stored in the ECU of the M5? These files can only be read by BMW and not the dealer.

Any Help would be fantastic.


JDS
 

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Who can tell me if an E60 M5 with SMG3 transmission can or cannot be over-reved? I know that there is a rev-limiter on accelleration
and that when requesting a downshift with the revs close to the redline, the SMG will not allow the downshift and the gear number will
flash to prevent the over-rev. Is this correct?????

Does anybody have any knowledge about the FAstfa secret code that is stored in the ECU of the M5? These files can only be read by BMW and not the dealer.

Any Help would be fantastic.


JDS
You're right the SMG won't allow a downshift under most circumstances. However I've seen an E60 M5 over-rev from downshifting into an incorrect gear.

I'm assuming your trying to purchase an M5 and want to make sure it hasn't been over-reved? If the car is CPO'd, that means it has a warranty so could not be over-rev'd.


Are you not purchasing a CPO? This isn't a buy from a dealer?
 

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Discussion Starter · #3 ·
avInch,
I'm trying to prove that BMW has not informed their customers properly of an over rev condition. To me the point of the SMG3
transmission was that it is a computer that makes the correct decission on rev limiting and gear changes so as not to do
what a driver can do with a manual transmission. When you downshift, the computer will match the revs for the lower gear. If
the RPMs are to high, the gear indicatir will blink and not allow the downshift. You cannot slect the next downshift until the first
downshift is completed. How have you seen an over-rev in an incorrect gear? Please describe.

JDS
 

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avInch,
I'm trying to prove that BMW has not informed their customers properly of an over rev condition. To me the point of the SMG3
transmission was that it is a computer that makes the correct decission on rev limiting and gear changes so as not to do
what a driver can do with a manual transmission. When you downshift, the computer will match the revs for the lower gear. If
the RPMs are to high, the gear indicatir will blink and not allow the downshift. You cannot slect the next downshift until the first
downshift is completed. How have you seen an over-rev in an incorrect gear? Please describe.

JDS
The point of the SMG is to rev-match, and change gears more efficiently than a manual version.

First, you can downshift multiple times. If you are in 5th gear, you can double down to 3. If you are in 7th, you can triple down to 4th. All providing you will not be over-reving (ex. from 3rd at a high rpm into 1st.. smg shouldn't allow it).

I never downshift to too low of a gear. Only once when I first took delivery of my '08 M5 (first M) and it would NOT do it.

There is always a chance for the engine to blow. With SMG they are slim (compare to manual), but still possible in some situations.. I believe only extreme situations (pushing the car hard). For example, the computer will not allow an over-rev, however if the driver downshifts to the MAXIMUM RPM limit allowed BEFORE the ECU disallows the operation, WHILE keeping their foot on the pedal, the car will bounce off the rev limiter/over-rev.

You can see why the chances of over-rev are slim.

Basically although BMW has set precautions, an over-rev is still possible. Some members here have had their warranty voided because they have had an over-rev logged onto their ECU.
 

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I have never seen a stock e60 m5 smg over-rev. only way to do this is with a diff to throw the computer off on rpm and then it will allow a downshit into red.

Their is a way for bmw to tell if it has been over-reved, don't know if a dealership will do that for you tho.
 

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I let a relative drive my M once and he bounced off the rev limited a bunch of times

I have never seen a stock e60 m5 smg over-rev. only way to do this is with a diff to throw the computer off on rpm and then it will allow a downshit into red.

Their is a way for bmw to tell if it has been over-reved, don't know if a dealership will do that for you tho.
He was confused as to how to upshift with the Paddles. Now, if BMW decided to void my warranty for that it wouldn't be nice.
 

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He was confused as to how to upshift with the Paddles. Now, if BMW decided to void my warranty for that it wouldn't be nice.
Bouncing off the rev limiter != overrev.

So it looks like no one has ever seen a confirmed case of a stock SMG car overreving?
 

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I don't believe hitting the rev limiter is over revving from a warranty standpoint, since I'm sure everyone has hit the rev limiter before.

I have watched these forums for the entire life of the e60 and I only recall a 6mt getting warranty voided for over rev
 

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Hitting the rev limiter in a stock car will not be classed as an 'over-rev'. BMW (as do all car manufacturers) set the rev limiter at a safe position so that as a driver we cannot get anywhere near the point of over-revving. I'd imagine that if the car was mapped and had the rev limiter raised then BMW would have an issue with you being able to go beyond the stock limits - remapping = void warranty. Tests have proven, as im sure //M will have also done that you can drive most cars on the rev limit all day long and the only thing you will affect is the engine temperature. You might well be putting alot of strain on the oil but its nothing near what the oil can cope with. The only problem i would have (other than the fact its stupid) is that you would be putting more mileage on the engine than on the clock.
 

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The whole point of a rev limiter is so you don't over rev! Having said that, I highly doubt this engine cannot handle revs exceeding 9000rpm!
 

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If anyone notices the S85 appears to have a "yellow zone" and then a "red zone."

I've always taken that as don't go into the red and don't drive for prolonged times in the yellow (meaning if you are accelerating through the yellow zone, fine, but don't cruise in it).

If anyone has noticed, the SMG won't even typically downshift into the yellow zone.
 

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The manual says to NOT enter the red.
 

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The manual says to NOT enter the red.
Well, I think any person with any sense would take the red zone as one that should be avoided.

I was simply saying that if you look at the tach of a factory S85 powered vehicle (that is M5 or M6), you'll notice that from 0-7750RPM, the tach is white or unmarked, from 7750 to 8250, the tach is yellow, and from 8250 to 9000, the tach is red.

From my experience driving our SMG equipped M5, the SMG will not even allow a downshift into the yellow zone, let alone the red, so I find it very hard to over-rev an SMG equipped car by way of downshifting.

The only way I'd see is if you were in a gear and let the car roll down a hill bring the RPM's above redline, but I don't think this is even possible considering how significant the S85's compression braking is.
 

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Mine revs up to 8500, but it's totally useless in lower gears.
 

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Ahmed said:
The whole point of a rev limiter is so you don't over rev! Having said that, I highly doubt this engine cannot handle revs exceeding 9000rpm!
I agree Sir.

Look at the Audi V10. It revs up to 9000 RPM stock. No problems at all.
 

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The manual says to NOT enter the red.
Page 62 of the 2008 manual states to "shift at the latest when the red indicator field lights up" and that when the maximum engine speed is exceeded that "fuel will be cut off to protect the engine."

Further, the manual states on page 60 the SMG will prevent mechanical over-revs by not allowing the downshift...
 

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My manual is in my foot! LOL
 

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I am very confused. If only BMW can see these legendary overrev codes how can anyone in their right mind buy a used M5? How do we know that the previous owner did not overrev? I had my M5 inspected by the dealer prior to purchase and I specifically asked them to check for overrev codes etc. and they told me they could not do such a thing. So, if a buyer cannot check the overrev situation prior to purchase through the dealer network but the magical BMW factory reps can void your warranty based on these otherwise undetectable codes, has BMW effectively killed the used M5 market?
 

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Well, I think any person with any sense would take the red zone as one that should be avoided.

I was simply saying that if you look at the tach of a factory S85 powered vehicle (that is M5 or M6), you'll notice that from 0-7750RPM, the tach is white or unmarked, from 7750 to 8250, the tach is yellow, and from 8250 to 9000, the tach is red.

From my experience driving our SMG equipped M5, the SMG will not even allow a downshift into the yellow zone, let alone the red, so I find it very hard to over-rev an SMG equipped car by way of downshifting.

The only way I'd see is if you were in a gear and let the car roll down a hill bring the RPM's above redline, but I don't think this is even possible considering how significant the S85's compression braking is.

I have done that, shifted from 2nd into 1st and the engine bounced to almost 8000 rpm.
 

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If the SMG software is unmodified ie. factory fit then surely as a driver we cannot reach a point at which the engine will over-rev. There will be software to prevent this - rev limiter????. If there is such a risk or flaw then isnt that BMW's fault? This is in reality a racing spec saloon / tourer and has been designed to be pushed on the road and when called upon, on the track. If we are not allowed to use the full rev range then why design it and advertise it to rev as far as it does? This was one of BMW's boasts when they unveiled the E60 M5.

If BMW told me that my warranty was void due to over revving and my car was standard then i'd throw the book at them. No question about it. Design flaws are down to BMW to resolve, and over-rev codes would be a design flaw in my eyes. Im not convinced these codes even exist.

To put it in some context, its like having a two storey house built and the builders telling you that you cant use the stairs. Or buying a boat and the manufacturer warning you that it might leak or dissolve if placed on water. Over revving a standard car is bollocks, you cant do it.
 
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