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Discussion Starter #1
I noticed the other day as I was leaving in a hurry (dsc off) that when I spin the tyres, the rear end seems to jump around allot.. I dont know if it was just the tyres/wheels or my entire rear end.. It was very strange, It did not spin the wheels smoothly.. I remember having to install traction control braces on an old Hot Rod I had because of similar issues.. Do M5's have the Subframe cracking issue ?:3:
 

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Point #1...the m5 is not designed as a drag racer...

So, the m5 sufferes from some axle hop under hard acceleration and it is important that you (or anyone) keep that in mind. There have been some members who have had subframe cracks occur and BMW has been very unwilling to help. I believe that the more powerful Dinan S2 pkgs have shown this subframe problem as well...

I would suggest you search the archives for the term "axle hop"
 

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Yeah, i've had this problem too, and also remember traction bars from the muscle car days. Additionally, i get some wheel hop on hard acceleration with the 1-2 shift, going into second. It'd be nice to see a solution, other than not accelerating hard!
Mike
 

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Discussion Starter #4
mottati said:
Yeah, i've had this problem too, and also remember traction bars from the muscle car days. Additionally, i get some wheel hop on hard acceleration with the 1-2 shift, going into second. It'd be nice to see a solution, other than not accelerating hard!
Mike
I have to agree with you, Ive driven many high performance sedans and rarely experienced this issue. The rear end on the M5 is just very stiff in my opinion, but i guess thats the way it should be.:M5launch: :byee55amg
 

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I remmeber coming on this board ans asking the same question about a year ago... i got alot of difference answers, amongst them were answers like " thats normal.. just feather the throttle to minimise it" and answers like "check your drive shaft" etc etc.

Well....the axle or "wheel hopping" as it may be called stopped when one day as i was installing my IATS kit, i noticed the differential mounts were worn out! Which makes the whole differential move up and down when accelerating.

If you get wheel hop, avoid it as much as possible, cause it will get worse. And when it does, your differntial mounts are probably gone! Get them replaced and the M5 should launch the way it was designed to. The only problem is .... wheel spin like crazy!!!!!

The only thing that made me think it was normal in the begining was the fact that my brother's 996 Carrera 2 does the same. I still havent been able to figure it out!
 

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Ahmed said:
... your differntial mounts are probably gone! Get them replaced and the M5 should launch the way it was designed to..!
My M5 wheel hopped from the very first time - 1200 miles, so I doubt it was because of worn out diff mounts. That being said - loose, worn out ones on older cars certainly won't help matters any.

It's just the nature of THE BEAST. If it's any consolation, the Caddy CTS guys bithc about it, too.
 

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Discussion Starter #9
Now Im wondering all kinds of stuff... You guys are just too darn informative..;)

I notice that going into 5th and 6th i get too much of a kick sound from the diff.. Its hard to engage it smoothly and quietly.. Maybe some bad supports somewhere..Probably why I get extra wheel Hop too.. :3:

The only thing keeping me smiling right now is that I'll get to be back in the States for Christmas !! :2: :2: Vacation Approved !!:M5launch:
 

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atlantisvip said:
Now Im wondering all kinds of stuff... You guys are just too darn informative..;)

I notice that going into 5th and 6th i get too much of a kick sound from the diff.. Its hard to engage it smoothly and quietly.. Maybe some bad supports somewhere..Probably why I get extra wheel Hop too.. :3:

The only thing keeping me smiling right now is that I'll get to be back in the States for Christmas !! :2: :2: Vacation Approved !!:M5launch:
hey there buddy...

what you are experienceing right now, I DID TOO! It was so annoying cause even slow rolling accelreation, when depressing the clutch, there would be a kick!

Changing the differential mounts solved the problem! Also, what the mechanic told me was that every time i shifted, the differntial would move up and down to such an extent, that it was hitting my supersprint exhaust!!!!!!! Can you believe it???

Glad i got is fixed early!
 

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Discussion Starter #11
I have a feeling my diff mounts are due for replacements Ahmed.. It might also be the reason Im getting so much vibration from the rear..:cheers:
 

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atlantisvip said:
I have a feeling my diff mounts are due for replacements Ahmed.. It might also be the reason Im getting so much vibration from the rear..:cheers:
they are inexpensive, but the devestation they cause is! Get them replaced immediately before it gets too serious! You will walk out of the dealer a happy man!
 

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Discussion Starter #13
i just wish i could find a good service garage.. x service center will not install any parts unless i buy them from there.. i get them much cheaper so i need to find myself a new garage
 

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The Caddy CTSv guys are having this issue as well.
 

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If you have run flat tires that doesn't help. Try different tire pressure's go up two pounds and if it helps keep going till your happy or go down from your starting point and see what she does. It worked for me till i sold the beast. ;)

Robert
 

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bluemax said:
If you have run flat tires that doesn't help. Try different tire pressure's go up two pounds and if it helps keep going till your happy or go down from your starting point and see what she does. It worked for me till i sold the beast. ;)

Robert
its a 99 model M5, i dont think they had that option back then!
 

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Discussion Starter #17
This is in response to tire pressure.. As most of you know, tire pressure goes up an average of 2 pounds after some highway driving.. So if I set my (cold)pressure at 38 pounds, in reality Im driving at 40. So do most people determine their tire pressure as cold or what it will be when hot ?:typing:
 

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Have the same issue (on the sticky strip) with NEW mounts, new diff, new everything, so I guess its a design thing, the M5 is simply not made for 10 sec 1/4 mile runs :)
 

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atlantisvip said:
This is in response to tire pressure.. As most of you know, tire pressure goes up an average of 2 pounds after some highway driving.. So if I set my (cold)pressure at 38 pounds, in reality Im driving at 40. So do most people determine their tire pressure as cold or what it will be when hot ?:typing:
Most people refer to tire pressures when cold. Best time to check is first thing in the morning, not in direct sunlight. :M5launch:
Regards,
Jerry
 

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Sorry to bring this old thread back up, but I have a concern.

So if my tires are not breaking loose or I am unable to do a burnout, could this mean I have a bad rear diff or bad differential mounts?
 
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