What's wrong with my strut?

[Twilight138]

While changing my oil yesterday I noticed my front right strut was wet; small oil stain on the drive way also. Here some photos. Doesn't look like an active leak but definitely something coming out. Drives fine.

Car is still under CPO warranty, anyone have an experience for suspension related warranty repairs and the dealerships willingness to change it out. If not I'll do the work myself if y'all have some recommendations for struts. Thanks a ton!

2017 15 35D

[-c-]

Originally Posted by Twilight138

While changing my oil yesterday I noticed my front right strut was wet; small oil stain on the drive way also. Here some photos. Doesn't look like an active leak but definitely something coming out. Drives fine.

Car is still under CPO warranty, anyone have an experience for suspension related warranty repairs and the dealerships willingness to change it out. If not I'll do the work myself if y'all have some recommendations for struts. Thanks a ton!

2017 15 35D

Looks like you blew a strut. The oil in the strut blew out. Sometimes hitting a pothole can do that or just rough streets and they just fail. You can see oil splatter on your rim as well so probably most the oil in the strut is gone so it's performance is reduced. The other strut is taking up some slack from keeping you bouncing as it's connected through the sway bar. But yea your rebound is also effected.

Time to replace it for sure.

[phipark]

yep, it's blown. needs to be replaced.

[M302_imola]

Are these not gas struts? Maybe a mixer of gas and oil?

[Twilight138]

Replaced both my front struts with Bilstein B4s (22-240316). Pretty easy job to do yourself. Couldn't find much out there for the F15s on how to do it so took a little longer than I wanted. 4 hours for the first and about an hour for the second. Worth the savings.

[turboawd]

Originally Posted by Twilight138

Replaced both my front struts with Bilstein B4s (22-240316). Pretty easy job to do yourself. Couldn't find much out there for the F15s on how to do it so took a little longer than I wanted. 4 hours for the first and about an hour for the second. Worth the savings.

You think those are as good as oem?

[M302_imola]

Originally Posted by Twilight138

Replaced both my front struts with Bilstein B4s (22-240316). Pretty easy job to do yourself. Couldn't find much out there for the F15s on how to do it so took a little longer than I wanted. 4 hours for the first and about an hour for the second. Worth the savings.

Was the blown front right strut making any noise or was the ride more harsh on that side? Any irregular tire wear on that side? I'm trying to diagnose what I believe is a faulty front right strut as well.

[Twilight138]

Originally Posted by M302_imola

Was the blown front right strut making any noise or was the ride more harsh on that side? Any irregular tire wear on that side? I'm trying to diagnose what I believe is a faulty front right strut as well.

Sorry for the insanely delayed reply. Honestly it felt pretty dang normal. No sounds coming from it. Once I noticed the oil leak I did start to notice it took bumbs harder. And pushing down on the blown side the car felt less tight. For me it was the oil leaking down the strut that was the dead give away

[Twilight138]

Originally Posted by turboawd

You think those are as good as oem?

I think they are equal to the original struts. Can not tell a difference in driving

[Smoove.]

Anyone else with B4's on ride quality? I am due for a suspension refresh and comfort is priority as it's for my daily but I can't find much on B4's for our platform other than its equivalent to OEM but 10% stiffer. I'd like to stick with OEM but at nearly double the price of B4's it'd be a no brainer to go with B4's if the difference is minimal.

[tlow98]

The b4s are fantastic. I installed them on our x5 about 10k miles ago.

For the money, there’s no reason to go OE. Bilstein will last as long of not longer than OE stuff. Heck, many times they are the ones that make the OE stuff.

I still need to install the tears, but the difference was huge with the fronts replaced.

[Smoove.]

Originally Posted by tlow98

The b4s are fantastic. I installed them on our x5 about 10k miles ago.

For the money, there's no reason to go OE. Bilstein will last as long of not longer than OE stuff. Heck, many times they are the ones that make the OE stuff.

I still need to install the tears, but the difference was huge with the fronts replaced.

Thanks for the reply that's good to hear! So is it safe to assume they ride as comfy as oem and not some what rough? Although not our particular chasis I've read to some it rides a bit harsh after 500-1000 miles which had me some what worried.

[tlow98]

Well, you know it’s hard to say how they compare to new OEM as I’ve never experienced that.

You’d need to find a car with very low mileage or buy new ones. They definitely feel identical or nearly identical to when I first put them on. They certainly haven’t degraded in any way that I can tell.

If you look more broadly across nearly all BMW platforms (e36, e46, e90, f30, blah blah) you’ll see reviews on the following stock replacement struts:
Koni yellows - best balance of ride/performance for low speeds, great in town ride behavior
Bilstein b8/6 - best at high speed absorption, but around town can feel harsh
Bilstein b4 - best as stock replacement. Mostly imperceptible from stock.

I’ve owned them all on various platforms. If the Koni Yellows were available for the x5 I’d have bought them. If they make them in the future I’ll buy them. They’re just so plush and at the same time control the body so well.

The B4s I installed for the X5 to function as stock in a car that’s mostly driven by my partner. I love tight new feeling suspension. IMO, it’s the part of the car you enjoy the most - turning, braking, accelerating and steady state cruise all are impacted by the suspension. My partner commented how much better the car rides, brakes and handled but mentioned nothing about hard ride.

Is stock OE better? Maybe. But in which category and by how much? Hard to say.