[eleven11]

I've been dailying my F31 xDrive ~50,000 miles on lowered KW DDC coilovers. Overall, I like the suspension. However, even after raising the height, coilover binding is very common for the front. I've worked with the best shop in the region, who tried multiple adjustments. Ultimately, they ended up wrapping the front coils with a rubber hose material (maybe 30% coverage of the entire coils). This worked very well, eliminating nearly all of the noise/harshness, without any significant loss of function. However, after so many thousand miles, they eventually start to work loose and are a pain to remold to the coils. I've zip tied them, but they eventually fail.

So, I'm curious if anyone has a solution or similar product? Here is an old thread where a user DIY'd a simple solution: https://www.e90post.com/forums/showthread.php?t=609774

I appreciate any feedback.

[Zoomz]

Following—I may be having a similar problem with my newly installed coilovers.

[jmanB45]

If your front springs are #2039, they are too soft for the car. I had a similar issue with my KW Comforts, the correct springs are #2041 which are suitable for gross front axle load of between 1001 to 1090 kg.

Detailed in this thread from #18:
https://f30.bimmerpost.com/forums/sh....php?t=1799518

[eleven11]

Originally Posted by jmanB45

If your front springs are #2039, they are too soft for the car. I had a similar issue with my KW Comforts, the correct springs are #2041 which are suitable for gross front axle load of between 1001 to 1090 kg.

Detailed in this thread from #18:
https://f30.bimmerpost.com/forums/sh....php?t=1799518

Very interesting. Thanks for sharing - I've never stumbled on that thread before. It's been many years, so I'll need to get out the included manual and review. I assume the number is printed on the coils?

[jmanB45]

Yes, the part # is printed on the springs. You can also find the info on the installation instructions which came with your kit. PDF can be downloaded from https://www.kwsuspensions.com/products.html

Looking at the DDC kit for F31 X-Drive, I can indeed see it shows 2039 springs. Note it also shows the max front axle load as 1000kg.

The axle load information for my car is at the bottom of the B pillar. My front load is 1020 kg. I'm sure yours will be the same or higher.

[eleven11]

Originally Posted by jmanB45

The axle load information for my car is at the bottom of the B pillar. My front load is 1020 kg. I'm sure yours will be the same or higher.

I just checked my vehicle: F = 1005kg, R = 1230kg

Again, very interesting. I'm curious why KW went with the 2039 (pending my verification)?

On quick search, it doesn't look like I can simply order the 2041 springs directly, so a phone call to KW is in order. Correct me if I'm wrong (noting your situation was remedied by contacting KW). With the age/miles, I'm not expecting this to be covered by any warranty.

[jmanB45]

Once I pointed out my front axle load was higher than specified, they admitted "there was a mistake on this kit in our u.s website & u.s app guides"

I would try to get them to replaced under warranty, I believe it is lifetime? Otherwise, they are relatively reasonable at $90 each plus shipping. They're happy to sell individual parts.

You might also be interested in this vid by FaRKle!, he uses even stiffer springs on his F31 (#2025 from the M4 convertible kit). With this route, the rear springs need to be stiffer as well.

[eleven11]

Originally Posted by jmanB45

Once I pointed out...

Great information. Thank you.