BMR / Viking Crusader constant rattle

[gqneon]

I installed the BMR SP088/089 springs, Viking crusaders and BMR mounts - and I'm getting a near constant rattling from the right rear shock area at low speed and especially if there's uneven pavement. I'm just test driving the car so when I heard it I put it back in the garage. I pulled the right rear wheel and the jam nut and small washer beneath it were able to move. I think I need to crank down the spherical end bearing farther but don't have a way to torque it further as there's no obvious way to keep the shaft from rotating when I try.

Anyway I torqued the nut down again so it and the washer didn't move but the noise was still present - I didn't have any more time to mess with it so I don't know if it loosened back up in 50 feet of driving but I doubt it. No squeaks - and the driver side doesn't seem to do anything like it at all. You can hear the shock valving clearly with bumps etc but it doesn't bother me at all.

To me it sounds like something's clearly loose - but other than what I noted, everything's torqued to spec after preloading suspension.

Thoughts? Thanks!

There are other threads about rattles/squeals/etc - but here's a video of the sounds mine makes from the passenger rear since I didn't find one like it.

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[turnswrench]

There are other threads about rattles/squeals/etc - but here's a video of the sounds mine makes from the passenger rear since I didn't find one like it.

Crap, that's a lot. Sure there's no way you missed something? If you can quickly swap the shocks from one side to the other, see if the sound follows. Could be a defective shock?

 

[Roadway 5.0]

That is discomforting. Did you check the four bolts holding the shock in place (2 up top on the mount, two low on the base)? Sometimes the two low ones can be deceiving whether they are fully tightened or not.

 

[NastyPumpkin]

Wow! That sucks, I was thinking about getting these shocks too.

 

[gqneon]

I torqued the top ones to 66 lb/ft and the bottom ones were around 37 lb/ft and they all appeared intact and tight - but I wonder about the shock mounts and the hardware . I waited a week and half for the updated hardware (smaller washer and taller nut) but it seems like the threaded spherical end is barely can be closed to meet the gap between the spherical end, the nut and keeping the washer from moving. I also couldn't find a torque value for the top strut mount bolt/nut anywhere (there were no instructions so I just went by the picture bmr posted somewhere on the forum.)

So it's entirely possible it's something simple and that I've improperly torque that or that I may need a washer under the jam nut or something. Rides really well and quiet other than that. Just wasn't sure if the sound stood out to anyone as something specific.

 

[gqneon]

Crap, that's a lot. Sure there's no way you missed something? If you can quickly swap the shocks from one side to the other, see if the sound follows. Could be a defective shock?

I'll try this if it looks like nothing else is fixing it - it would be a good test. I'd like to think the shocks fine and I've just missed something.

I took for granted how nice and easy the stock shocks are to install the bottom bolts to - the bolt , two washers and a nylon nut are a lot trickier in that space with the aftermarket axles in especially on the drivers side.

 

[BMR Tech]

The washer, nut and bearing end should all be tight. If they are, then the noise is not coming from that location. The nut should be snug to the washer, then you tighten the bearing down against the nut.

Feel free to give me a call tomorrow to discuss.

 

[gqneon]

Ok, I talked to Kelly earlier and afterwards pulled apart my shock top mounts.

I used a good bit of blue loctite on the base of the threaded portion of the Viking shock rod. I set the small washer over it and ran the taller nut down as tight as I could with a wrench and spanner wrench on the top of the shaft. This was much tighter than I had done before. Then I put loctite on the threads from there up and hand threaded the spherical end until the nut made contact. Then I used two wrenches to apply a solid amount of torque to drive the spherical end and nut together and reinstalled the mount to the body. This resolved the issue and confirmed I needed to modify my installation / torque values.

The top bolt and nut that goes through the spherical bearing, per BMR, is 46 lb/ft, since I didn't see that anywhere else.

When I got to the right side shock mount, the small washer and tall nut were nice and tight but the mm gap between the spherical bearing base and the nut allowed a tiny bit of vertical movement. Moving this up and down by hand it was readily apparent that was the rattle I was hearing.

Test drive revealed the rattle is gone.

So, win win! And the hammer tone looks good!

 

[BMR Tech]

Woohoo! Happy you got it resolved, now enjoy!

 

[DavidHuff]

Ok, I talked to Kelly earlier and afterwards pulled apart my shock top mounts.

I used a good bit of blue loctite on the base of the threaded portion of the Viking shock rod. I set the small washer over it and ran the taller nut down as tight as I could with a wrench and spanner wrench on the top of the shaft. This was much tighter than I had done before. Then I put loctite on the threads from there up and hand threaded the spherical end until the nut made contact. Then I used two wrenches to apply a solid amount of torque to drive the spherical end and nut together and reinstalled the mount to the body. This resolved the issue and confirmed I needed to modify my installation / torque values.

The top bolt and nut that goes through the spherical bearing, per BMR, is 46 lb/ft, since I didn't see that anywhere else.

When I got to the right side shock mount, the small washer and tall nut were nice and tight but the mm gap between the spherical bearing base and the nut allowed a tiny bit of vertical movement. Moving this up and down by hand it was readily apparent that was the rattle I was hearing.

Test drive revealed the rattle is gone.

So, win win! And the hammer tone looks good!

PM Sent

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