Bilstein 5100 with FJ Spring problem

[Rjameseast]

I am reaching out to see if anyone has had any issues with the Bilstein 5100 setup with the FJ springs. I installed the 5100's on the highest setting on the front with the 5100 rear shock and daystar spacer on rear about a year ago without any issues on my 2005 v8 sport. I recently obtained a full set of barely used springs from a 2009 fj. After driving with them for 3 weeks, the ride was noticeably better, but my right rear shock broke under the mount at the base of the nut on the 5100. It happened when compressed as I was turning left slowly into my driveway which has a slight incline. Has anyone had issues with this? I looked all over and haven't found much. Bilstein replaced the shock which I installed and it seems fine, but I want to prevent any future issues. I originally had them installed at a local mechanic which seemed to be installed correctly. There is not much to mess up with a rear shock. Any suggestions?

 

[Rjameseast]

Sorry for the large pictures. Here is the shock after it broke. Notice the shock body slid forward.

 

[gm350reratliff]

No issues here. I've been running the FJ spring/ 5100 @ 1.75" (front) and FJ spring/Daystar 1.5" spacer/ 5100 shock combo for 5 years (70k miles) on my 4th gen. It probably was defective from the get go. I wouldn't worry about it.

 

[Rjameseast]

Thanks for letting me know. I was thinking the same thing that it may have just been defective. It's odd how I had no problems for a year until I added the FJ springs.

 

[blackoutt]

Need to make sure that the shock's shaft is centered in the hole on the frame when the upper nut is tightened. There should be some centering features on the rubber bushings both top and bottom to help with this if installed correctly. If the upper shock mount bushings were installed upside down it could have allowed the shock shaft to rub against the frame and create a more stressed area. See the shoring marks on the edge, then the fast fracture once it finally decided to go (right when you put a higher load on it going into your driveway). I wouldn't worry about it happening again as long as it's installed correctly.

 

[Rjameseast]

That makes sense. I did not install the shocks the first time. When I got the replacement, I used a new bushing on the bottom and the original bushings on the top because another new bushing would not fit. I also read that somewhere on this site. That's also how the mechanic installed them. I put the bottom bushing on correctly with the raised groove facing the hole. The upper bushings are 2 sandwiched together. Should they be replaced with a new bushing and how do you go get the nut to thread on? Thank you.

 

[T101]

That makes sense. I did not install the shocks the first time. When I got the replacement, I used a new bushing on the bottom and the original bushings on the top because another new bushing would not fit. I also read that somewhere on this site. That's also how the mechanic installed them. I put the bottom bushing on correctly with the raised groove facing the hole. The upper bushings are 2 sandwiched together. Should they be replaced with a new bushing and how do you go get the nut to thread on? Thank you.

You should have new bushings on both sides, and should be able to thread the nut pretty easily.

Do you remember removing a metal washer from the truck when you pulled
out the old shocks?

When I did mine (same 5100's) a couple weeks ago a metal washer from the stock shocks was rusted/stuck onto the mounting point. It lied on top of the bottom bushing, in between the rubber bushing and the mounting point of the truck. It was on there so solid that at first I thought It was part of the car. I used the new bottom and top bushings, and couldn't get the nut to thread either. I pulled the 5100 back out, then after a few good whacks with a hammer that old metal washer came off. After that the 2 new bushings fit just fine.

 

[mallard]

No issues here. I've been running the FJ spring/ 5100 @ 1.75" (front) and FJ spring/Daystar 1.5" spacer/ 5100 shock combo for 5 years (70k miles) on my 4th gen. It probably was defective from the get go. I wouldn't worry about it.

Running the same setup with no problems over a year now. I'm with the defective thought line.

 

[Rjameseast]

Thanks for the info. I will double check for the washer and get the new bushing on the other side. I also am thinking this was a defective shock. Do any of you know where I can get another bushing for the top of the left rear. The mechanic installed them a year ago and did not give me back the bushings. I never noticed. I know I can go through Bilstein, but didn't know if a local auto parts store would carry something like that.

 

[Rjameseast]

Just letting everyone who does this install know that I heard back from Bilstein. After reviewing the pictures, they said the shock probably broke because the nut was torqued too much. They said it looks like it was installed with an impact wrench. It may have been installed that way because I had the. Installed by a mechanic. Anyway, Bilstein sent me new bushings and I was able to get both installed above and below the bracket. Seems fine now. They said that will allow more side articulation and prevent the shock stud from snapping.