Worried with those subframe stories

[MCSL]

So is it possible for a 'replacement' floor to again.... crack?

[Monkey]

Originally Posted by Mike R

Danny,
Do you know if the replacement floor sections have been redesigned with the dowels, or are they the exact same?

Looking at the photos of the new section that Mark posted up, I am unsure of the differences?

The new boot floors are exactly the same. Gorilla, we have seen 2 replacement boot floors fail again within a 3 year period of the repair.

[shane@mbtech]

Just go full weld in cage. Job done.

[JBird]

Originally Posted by Monkey

The new boot floors are exactly the same. Gorilla, we have seen 2 replacement boot floors fail again within a 3 year period of the repair.

With the foam fill?

[mick csl]

when i bought my csl I also concerned about the subframe stories.
My csl with 45k miles had no cracks, but let them welt preventive the reinforcement kit on the car.
when i read the horror stories on the web every e46 M3/M3 CSL will get it at some time of its life.
(I paid 1000 euro for the job with new subframe bushes, PSG Geel M specialist in belgium)

(Sorry for the bad english)

[mattCSLnut]

Originally Posted by DuncanR

BMW are having a fookin laugh saying that this doesnt happen and denying it in Germany ..then coming up with Technical Bulletins and stupid crazy foam fixes ... I may write a letter to them and say Im going to drive around in it until the floor gives way and kills me ! ... then I will sue them

That could work BTW good to see you back on here matey

[JBird]

I would be interested to hear if any forum members who had a proper floor replacement and foam fill early on have carried out a detailed inspection since. Any signs of cracks or corrosion? I remember some ppl geting it done back in 09 - cant find the post though...only about 200 subframe threads! General search of tinternet doesn't find anything either - good sign i guess.

Originally Posted by Monkey

we have seen 2 replacement boot floors fail again within a 3 year period of the repair.

Monkey, do you recall the root cause of the second time round failures you saw, corroded welds poping, or genuine cracks in foam filled floors?

Originally Posted by Alx

I'm quite upset with BMW at the moment... On top of their recent ugly designs and turbo-engine philosopy, they handled this Problem quite badly

cheer up Alex, all the more reason to get the CSL sorted and hold onto it. Just incase you havn't seen it, clearly plenty of others who share your opinion mate....

http://www.youtube.com/watch?v=ZtenM...e_gdata_player

[Alx]

Haha, this one is a classic JBird.

It makes me laugh every time - thank you.

Like you, I'm interested to know if any car has failed after having the foam injections.

Thank you again everyone!

[The Gorilla]

Hi,

MikeR- no, they replace with more or less the
same panel etc, nothing is done with regard
to addressing the main cause, as its
a design flaw.

Go to any Chassis engineer worth his salt
tell him you have a triple layer sheet floor
section with two vertical folds and that the
fixing point for the subframe bolts are
spot welded in with top and bottom
flanges.

Then tell him that the subframe mounts via
4 H/T bolts all in the same plane to a flat
'seat' section and there are no Chassis
dowels for bush location.

Mention that one Bush has an elongated hole
in the alloy insert for subframe fitting,
and that under ''clamp'' the bushes are
no more than 60nm.

Then tell him you going to inject foam
or whatever to stiffen the the 3 layer
honeycoombe sheet, as the torque loads
from the diff, which is mounted solely on
the subframe, and the lateral G loads
into the bushes via the rear wheels,
CSL on Type R can pull close to
1.2/1.5 lateral G in some corners, are
ripping the mounts and causing sheet metal
fatigue and cracks.

A good one would ask what medication your
on and a poor one would tell you that
''it'' migh work, not sure but he available
if your require his services.

As a tail note when BMW developed the
M3 GTR, one of my favorite Race cars
of all time, one of the first things to go
was the E46 rear subframe.


Regards,

The Gorilla.

[alexk]

Danny the solution is very simple in my opinion.
We need to get an E46 M3 GTR chassis.