Location of lug bolt corrosion

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JHZR2

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Last year I didn't put snow tires on to my old BMW. It was just always so warm and I didn't have the time or the necessity. I just put them on today and the lug bolts had not been touched for about two years. Every one of them was incredibly difficult to remove. Difficult as in full leg muscles on a 4 foot bar, and I can squat a goodly amount of weight so it was a lot of force. The breaker bar was definitely bending and flexing in ways that I had not caused it to do before.

As each lug nut released, there was a distinct pop, indicating to me that there must be some spot corrosion that was causing localized seizing.

The car sits outside and so it gets wet every time it rains, and it gets road salt if there's some on the ground. The lug bolts are made of steel while the wheels are aluminum, which certainly does not help.

I don't want to create an argument about using anti-seize on lug bolts... But the amount of force that I had to use was extreme and also likely not correct. I'm wondering if there is some sort of a surface treatment, even if it's not an oily anti-seize. There is downside of corrosion at any of the mating surfaces.

But I'm wondering if perhaps use of something like Eezox or Boeshield t9 would help to prevent corrosion on the surfaces, while minimizing the torque offset which people are often concerned about.

Alternately applying anti-seize to one of the surfaces, either the seat on the wheel, the collar on the bolt itself, or the threads solely will get the treatment.

I couldn't even get the bolt loose with my Ingersoll-Rand impact gun, and if I would've ever had a flat tire, I would have definitely been stuck - no way I would've ever gotten these loose with the OEM lug wrench.

That's justification enough for me to do something. Thoughts??
 
I do not think a little oil from an oily rag wiped on the threads would be a problem.

When I cannot get a lug nut off, I use PB Blaster daily until I can get it off with an impact wrench.

I once used a pipe on a breaker bar and snapped the lug bolt (trailer). I had to bring the hub to a machine shop with a milling machine where they removed the broken off bolt and put a helicoil back in.

Or pull and retighten the lug nuts yearly.
 
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Perhaps antisieze on the mating surface, I would brush the bolts and clean them. I think threadlocker 242 (blue) being an anaerobic sealant might keep the threads from seizing and keep out the moisture and oxygen. 242 is designed for items that need disassembly.
 
I would clean with a wire brush - then hit the bolts and the hubs (including threads) with a shot of pure zinc primer...we see a lot of salt water down here...and had similar problems until I started using the zinc. That way, you're not using anti-sieze or "lubricant"...the primer leaves a dry coating...
 
I have seen anti sieze on countless wheel studs without concern. Just use common sense when tightening the nuts, usa a torque wrench at the low end of the spec. Air powered impacts will damage the wheel if the studs are lubricated. The clamping force will be increased somewhat but torqued evenly it will be fine.
 
I'm an antiseize user. But I don't reapply it every time I touch the lugs. One light application lasts a good long time.

Never apply it to the collar. I've witnessed controlled studies that show how harmful that can be.
 
Originally Posted By: Kestas
I'm an antiseize user. But I don't reapply it every time I touch the lugs. One light application lasts a good long time.

Never apply it to the collar. I've witnessed controlled studies that show how harmful that can be.



Wow, interesting. I would have thought that the collar would be the right place to put it. Do you have either a linkable study or can you explain further what happens? I kind of thought that the collar is where all the seizing occurs and where you would want to have the product...

Thanks!
 
Interested to hear about this too. I always assumed that antiseize could only throw off your torque values. Each lug applies a few thousand pounds of clamping force but I suppose there still needs to be friction between the hub and the wheel to stay together.
 
I use a small drop of machine oil on the lug threads only as anti-sieze can through the torque readings off if used on the collar. Definitely use anti-sieze on the wheel hub and mating surfaces as torque ratings do not apply here. I use "Zap" anti-sieze, works well.
 
I always have some oil or grease on the lug bolts of my e30. If I'm not careful where I lay them when I take them out they always seem to pick up dirt easier than a lug nut so I always wipe them down and re-oil. On all wheel studs and lug bolts once they're out I spray them down with PB Blaster then wipe them down, then put a bit of motor oil or grease on them and wipe them down again. I'll admit I've never used a torque wrench either.

BTW, how does a BITG type of person go 2yrs without touching their lug bolts? Don't wait so long next time. I crack them loose and re-tighten on the ground at least once a year just for "fun."
 
I have to wonder how much the bolt/stud "flexes" or distorts under driving. Maybe the two (or three, including the rim) gall or embed or otherwise get intimate after lots of load/unload, high temp / low temp kinds of cycling.
 
Lubricant on the collar dramatically reduces the amount of friction needed to turn a fastener. A long time ago we and our supplier were studying why there was a rash of broken stud bolts for one fleet. This involved lubricating different points of the stud and lug using different lubricants, and their effect on clamp load. We were trying to second-guess what was happening in the maintenance shops. For this case, we found that lubricating the threads and collar with never seize markedly reduced friction, to the point that the stud bolts cracked when torquing to the specified torque. This result stood way out from the other scenarios that didn't have lubricant on the collar.
 
Ouch.


SO if the collar is where my seizure is occurring, what would you recommend? Did your study come up with a practical solution? I do have some of that high zinc primer that was mentioned above...
 
I've never found collar corrosion to be a problem. I always imagined the groaning during removal of corroded lugs was due to corrosion of the threads. If collar corrosion is a problem, I'd recommend a penetrant for removal.
 
My problem is that I dont know where the corrosion that is causing the seizure is. And if it groaned, Id be ok... This is more of a POP as Im putting 1000-1200 lb-ft of manual force on it with my bar. Anything less and it wont budge, even my impact wouldnt.

I figured that it most easily wicks in at the interfacial point at the collar and wheel, as thats the most easily wetted point.

The lug bolts are some steel, but with a black coating, reminds me of black oxide drill bits.

The only spot where there is bright metal is at the touch point on the collar.

But no place is there white or flaky or powdery or rusty stuff, indicative of corrosion...
 
Originally Posted By: JHZR2
My problem is that I dont know where the corrosion that is causing the seizure is. And if it groaned, Id be ok... This is more of a POP as Im putting 1000-1200 lb-ft of manual force on it with my bar. Anything less and it wont budge, even my impact wouldnt.

I figured that it most easily wicks in at the interfacial point at the collar and wheel, as thats the most easily wetted point.

The lug bolts are some steel, but with a black coating, reminds me of black oxide drill bits.

The only spot where there is bright metal is at the touch point on the collar.

But no place is there white or flaky or powdery or rusty stuff, indicative of corrosion...


I highly doubt that the collar is the seizure point. It may contribute to some degree, but the majority comes from threads. There is simply not enough surface area, as compared to threads, to provide 1000 ft-lb resistance. I only lubricate the threads and I never had a hint of lug nuts being stuck.
 
Originally Posted By: JHZR2
The lug bolts are some steel, but with a black coating, reminds me of black oxide drill bits.

Those are phos and oil coated, a lower quality coating found in aftermarket or low end parts. Are those lugs OEM?

Is the collar steel against aluminum? These two surfaces naturally gall.
 
Originally Posted By: Kestas
Originally Posted By: JHZR2
The lug bolts are some steel, but with a black coating, reminds me of black oxide drill bits.

Those are phos and oil coated, a lower quality coating found in aftermarket or low end parts. Are those lugs OEM?

Is the collar steel against aluminum? These two surfaces naturally gall.


BMW OEM lug bolts. Yes, steel against Al. The lugs dont have a moving/separate collar like Ive seen on newer cars.
 
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