I've got a 2004 545i w/ sport package. My left front strut is leaking, so I am going to replace the fronts with the original sport model Sacks struts.




When I discussed this with my mechanic, I suggested since I'm at 130k miles, I should replace the rears too. To my surprise, he tried to discourage me from doing the rears until I get a leak from one of them. He says that it's his experience that if they don't leak, they don't lose their damping ability. This mechanic has a reputation in the community as being an honest guy/shop. Although I like the fact that he's not trying to cash in on what I think I need, I still wonder if new rear shocks wouldn't enhance my handling after 130k even if they are not leaking. Any thoughts?

 

As anything else replacing rears with new springs and mounts will improve handling and you'll feel the deference.

 

at 130,000 miles, your shocks are completely toast. Mine were toast at 94,000 and weren't leaking a drop. The fronts were so worn that when I had them out of the car I could compress the rod all the way in with two fingers. One of the rears was the same way, and wasn't leaking. Just because a shock isn't leaking doesn't mean it's not worn out.

 

In my opinion, the sport suspension on E60s, specifically the struts, are heavy duty rated. They will last longer than the base, non-sport, suspension, depending on your driving style (i.e. trying to avoid major potholes and severe bumps). My 2008 sport suspension is at 95K miles, and still feels firm in the twisties.

Remember, Sachs is a highly regarded maker of racing and competition shocks and struts. They make components built to endure rugged and extreme duty.

If you're wondering whether your rears are worn, just rock each corner up and down and see if the car bounces a lot. Then again, your car is over 10 years old, and since the fronts were leaking, might as well replace all four corners at once.

 

firm in the twisties, eh?

those are probably your active roll bars working

 

+1. dampers are shot at 130K.

 

You do realize the anti-roll bars are directly connected to the struts, don't you?

Yes, the active roll bars are mainly responsible for keeping the car LEVEL during lateral transitions. Since they are connected to the struts, if the struts are worn, the dynamic drive won't be able to do its job, and you would notice it. In a turn at speed, every suspension component is being loaded and stressed. So when I say my car is firm in the twisties, the entire suspension is working as it should, struts included.

I've changed out leaking struts before on my previous cars, so I know when it is time to replace.

 

Just to chime in.. I have 130K on the clock on my 08 535xi and I just dropped it on H&R springs. All Struts were perfectly fine, I was holding my breath since I figured if I had them out and it was bad.. it was going to be a dilemma what to do since I did not have any struts lined up.

The previous two owners took awesome care of them, they were still nice and clean with no surface rust etc on it. Heck, even all the stickers I could read

 

I would replace all four

 

Decided to replace all four corners with the Sacks for sport model from Brav Auto. Sadlly, two week back-order. It makes sense to me that a shock can be worn out w/o leaking. My theory is the seals that keep the fluid in are different from the ones on the "plunger" that provides the damping.


I also ordered new front tower bearings and installation kits for all wearable items. I'll have my local mechanic do the install. I want to get the suspension closer to new and enjoy it for a few more years. Will need to get the alignment at the dealer. They will get pissy that they didn't put the shocks on and come up with a reason to add an hour to the alignment job. Been there done that.


Thanks to all for the input!


Dean