Has this happened to anyone else? Control arm bushing failure.

[olgreydog7]

I have MM tubular front control arms. I was driving down the highway and felt some vibrations. It felt like the front wheel was loose if I hit 50 mph. I pulled off and went over a speed bump and could hear a thunk like metal on metal. I got the wheel off and found that my bushings in the control arm had failed. Just crumbled apart. The drivers side was just about to go as well. They were the urethane bushings. Anyone ever seen this? For the record, I plan to replace them with delrin.

 

[01yellercobra]

Not personally, but a buddy had poly bushings in stock control arms and he had to replace them over the summer. I don't know how many miles were on them.

 

[shurur]

I've heard of them becoming oblong around the sleeves...pics would be great.

Glad you're ok

 

[olgreydog7]

There's not much to take a picture of. All that was left in there crumbled when I removed them. It looks like red cookie crumbs on the garage floor.

 

[Nightmare90gt]

How many miles were on the bushings? Have you contacted maximum motorsports about the failure?What k member you running? How often did you grease the bushings?

 

[olgreydog7]

They've been on about five years, not sure on the mileage. Maybe a few thousand. I bought them used but never installed. MM helped me determine if they were theirs so I could get replacement bushings. Lots of MM copies out there, since I got them second hand I wanted to be sure. I've just never seen a urethane bushing do that before. I've seen really old rubber do that, but never urethane.

 

[SlowSVT]

Did you keep them greased? Urethane is not a good bearing material and it galls. Delrin is a much better choice.

 

[olgreydog7]

Yes they were greased. Though I don't think that would have had anything to do with this.

 

[shurur]

These bushings only get greased on the inside of the bushing where the bolt sleeve goes..correct?

 

[SlowSVT]

Yes they were greased. Though I don't think that would have had anything to do with this.

Urethane galls like hell without lubricant. It doesn't explain the disintegration of the bushing though. Maybe the casting resin was contaminated of not processed correctly.

 

[olgreydog7]

These bushings only get greased on the inside of the bushing where the bolt sleeve goes..correct?

No. There is a grease fitting on the CA.

Really the only thing that sees any friction would be the shoulders against the k member. Other than that the crush sleeve rotates on the bolt.

 

[SlowSVT]

The crush sleeve rotating on the bolt is not unusual for urethane as they are usually a press fit to ensure a tight fit. Once it starts to gall it will seize and starts rotating on the bolt which is not good. Articulating joints and urethane is not a happy union.