Koni FSD Shock Suspension Upgrade

[Nick82006]

Subject: 2011 N55 35i E70 X5 - Premium with base suspension

7/16/19 UPDATE: Right rear bottom shock bolt is seized up completely. I was able to turn it about 360* and it wouldn't budge after that. Used heat, PB blaster, impact, 4ft breaker bar. Wouldn't move. Took it to the local dealer, was quoted $1,700.00 to replace the entire swing arm/shock assembly (w/Koni supplied by me). Its hard for me to believe even the dealer wasn't able to get the bolt out. I understand if the labor involved to drill it out was more than 1,700 vs the cost of replacement i get it. @ $100/hr, it would take almost a full days worth of work? I am considering getting a second opinion in person.

ANY SUGGESTIONS on a CHEAPER way out of this pickle?? Hard to swallow that 1 bolt is gunna cost me that much $$.

7/8/19 UPDATE: 3 corners all buttoned up and ready to go. The right rear i have decided to take to a shop and have them take the stuck bolt out of the bottom on the rear right shock. I did not feel comfortable putting any more pressure on it while it sat on jack stands in my garage. If its going to snap, i would like for it to be at the dealer/shop when it does. Local Shop quoted ~500ish for install of that last corner plus alignment.



Problem: Knocking in the front when going over bumps, metal on metal.

Culprit: Previous owner replaced passengers side shock/spring with a Monroe quick strut. The very top rubber damper directly below the top nut/washer was missing, causing the innards of the strut mount (rubber) to break free and start knocking.




Parts replaced:
Lower control arms, tension arms, upper wishbone, sway bar end links front and back and the entire strut assemblies w/mount. The stock springs were used.




Progress: Front is 80% complete, just need to put everything back together and button up before final tq down. The rear however has been a PITA. I have searched high and low on this forum, others, youtube, BMW TIS and i cannot find the answer to the bottom nut which screws into the rear hub. The bolt is extremely difficult to turn, i am using a 4 foot long breaker bar and my fear is im going to snap this bolt off. Impact gun didn't do anything (not at 500ftlbs), its got plenty of PB blaster now for a couple days. i have made progress but they seem to be getting tighter as i unscrew. I feel like there is major tension on the bolts and i have seen conflicting procedures on how to remove these shocks.

I defer to the collective for advise.

[dennisvab]

Have you tried https://www.newtis.info/?

[Nick82006]

Originally Posted by dennisvab

Have you tried https://www.newtis.info/?

I have and 33 52 000 Removing and installing/replacing rear left or right shock absorber does note that a special tool is required to slightly compress the springs....is that necessary? I have a support underneath the hub on about 2 pumps worth of support.

[ard]

I sure hope nobody cross threaded those before you got there....



Is the shock semi loose on the bolt? So you know it isn't loading the bolt?

On the e39 that swing arm is over $500. Way over.

GL

[Nick82006]

Originally Posted by ard

I sure hope nobody cross threaded those before you got there....



Is the shock semi loose on the bolt? So you know it isn't loading the bolt?

On the e39 that swing arm is over $500. Way over.

GL

In fact i can move the shock around ever so slightly.

UPDATE: i was able to remove the drivers side, and after looking into the bore hole it "seems" like i was in fact eating some threads up...Not the best picture, thoughts?

[ard]

any thread/debris in the threads on the bolt???


If it was cross threaded, I would buy new bolts AND run a properly sized tap in and out of the hole. arguably, if a new bolt can be threaded into the hole without issues- only using light finger pressure- you might not need to run the tap.


Are those OE shocks? Or were those replaced previously? on occasion lower struts and control arm mounting bolts can fool you going back in. You are muscling the parts and dont notice the resistance isnt the parts but rather you are crossed...just saying.

[Nick82006]

Originally Posted by ard

any thread/debris in the threads on the bolt???


If it was cross threaded, I would buy new bolts AND run a properly sized tap in and out of the hole. arguably, if a new bolt threaded into the hole without issues, using light finger pressure, might not need to run the tap.


Are those OE shocks? Or were those replaced previously? on occasion lower struts and control arm mounting bolts can fool you going back in. You are muscling the parts and dont notice the resistance isnt the parts but rather you are crossed...just saying.

Not really any chewed up threads on the bolt itself. using finger pressure i can get the OE bolt in about an inch, then i would need a tool, i have ordered a new bolt. Those shocks were original BMW part number.

[robnitro]

Maybe you can get tap and it will hold well after that. If it feels loose after that, a thread insert might work well since thankfully there's extra metal around it.

[ard]

If it torques to the proper value, I'd run it....