MabesTT

As I removed my wheels for an Eibach/Bilstein upgrade, I found that several bolts would not release from my rear H&R 25mm spacers. It took a lot of work, but when I did get the lug bolts out several of them had a few of the aluminum threads from the spacer practically welded into them. There did not seem to be any misalignment of the lug bolt since this only occurred for the first few threads where the wheel and spacer came together. The rest of the threads on the end of the bolt and deeper in the spacer were fine. This affected two bolts on one spacer and four on the other. Any one else had this problem? BTW I had taken the wheels off and on several other times with no problems.

OddOrEven

Basically the dissimilar metals aluminum (spacer) and steel (lugbolts) allow this to occur. My understanding is this basically welds the metals together. Could avoid with anti-seize but putting this on lugbolts may not be a good idea either. Although past postings suggest a fair number of people here do use a small amount of antiseize.

I imagine more of a problem with the use of aluminum spacers (as opposed to steel)...

"There are three conditions that must exist for galvanic corrosion to occur. First there must be two electrochemically dissimilar metals present. Second, there must be an electrically conductive path between the two metals. And third, there must be a conductive path for the metal ions to move from the more anodic metal to the more cathodic metal."

Hope this helps. I just added spacers and used antiseize on all metal to metal contact but the lugbouts. Planning to just loosen and retorque regularly.

Run a google on GC for more.

Dar

GorTT

would be going too. You'd also see it on the mating surfaces. This just sounds like overtorquing.

MabesTT

It is possible I overtorqued the bolts on the aluminum spacer. I did go to the track this summer and may have been overly concerned about how the spacers would work (no problem BTW). I did torque my lug bolts to 120 Nm yesterday and it "felt" about as tight as I normally do it without the torque wrench. However, I will always use my torque wrench for lugs from now on.

I am probably going to pass on replacing the 25mm spacers and will just use 15mm spacers to allow the lug bolt to go directly into the wheel hub - avoiding any chance of galvanic reaction.

Thanks again for the thoughts!