Replace or re-use caliper bolts after brake job?

So just starting with replacing my pads and rotors. Just wondering if it is required to replace the caliper bolts, or can I re-use the same ones that I took out? If I need to replace, can I just get them anywhere (Sears?) or are they specialized?

Porsche recommends replacing them, so that's what I do. I've only bought them from Porsche dealers, so I'm not sure about other sources.

I agree with Dennis. Heat cycles in the bolts can make them weak especially if tracking the car. If you are in a pinch and need to get the car back together use the old ones, order the 8 new bolts and replace them when they show up. It will take you more time to jack the car up and get the wheel off than to change the bolts.

I have original bolts and pin. Car has been tracked extensively since 2005. Nothing wrong with reusing them.

People with no sense and money from Obama buy new ones, its not a tq to yield bolt and if heat cycles were an issue, don't you think the dealership would be calling you every week for a "scheduled" service ?? Of coarse Porsche wants you to replace them, its reoccurring revenue for them.. duh.. some people just are ignorant when it comes to a car and probably shouldn't be allow to own one.. much like a gun....you got to be smarter then what your working with.

You think people with "money from Obama" own Porsches? Interesting... By the way, your incoherent post might be more effective with proper punctuation, spelling and grammar.

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To each their own ......Dennis is being too nice in his response. In the spirit of Christmas I'm not going to tell you to fek off.....but sure am thinking it.

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Sounds like Hurdi after a drinking binge...could be him...

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+1. Pretty cheap peace of mind.

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I'm sure the head honcho at Porsche added a new wing to one of his mansions with just the extra income the new caliper bolts brought in. So this statement by you is right on the money: "some people just are ignorant when it comes to a car and probably shouldn't be allow to own one.. much like a gun....you got to be smarter then what your working with." I can only add that I hope you treat your car well. It is your intellectual superior.

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X2 The only bolts I replace are ones that are severely corroded, damaged, or one time use bolts like stretch bolts that are usually found in places like cylinder heads. I think in this day and age as enthusiasts, OCD, newcomers work on cars, we tend to probably over pollute by using more oil and throwing away more good parts than necessary. My $.02

I'd like to offer a little bit of help to weldingmachine. It is the season of giving, so let's help a fellow rennlister out. Here are my observations and comments to help: 1. The first post by weldingmachine in this thread is is second post on rennlist. As a result, we don't know him (or her). He hasn't established any rapport with this group, and hasn't established any credibility whatsoever. He may be a very knowledgable person when it comes to things like caliper bolts, but we don't know that. He may be a Porsche engineer who has done extensive testing on caliper bolts, but we don't know that. 2. The post that weldingmachine made is riddled with poor grammar, misspelled words and a lack of punctuation. Additionally, there is a butchering of the English language that is quite amusing. For example, "of coarse" doesn't mean the same thing as "of course"! (weldingmachine - look up "homophone" if you don't understand). This uncivilized manner of speaking may be used by weldingmachine as some kind of "artistic license" to make a point. Maybe he's really intelligent, but he speaks this way to bring attention to his point. Again, we don't know that because he hasn't established any rapport. 3. The post that weldingmachine made includes: politics, negative comments towards other forum members and deragatory statements towards Porsche owners in general. To most readers, this post seems like the incoherent babbling of a lunatic. Perhaps weldingmachine is trying to break the ice with our group by posting something that he thinks is funny. Maybe he thinks that his post will be so idiotic that people will find it amusing. We don't really know that. After thinking about this and reading the posts in this thread, our original poster, scorchpa, is left with two choices: 1. Take the advice of Porsche engineers and change the bolts. They really aren't very expensive. 2. Take the advice of a lunatic who can't put a coherent sentence together. This isn't a difficult choice. So my advice to weldingmachine is as follows: 1. Establish rapport 2. Establish credibility 3. Make your posts in a civilized manner, using proper English, grammar, spelling and punctuation 4. Behave in a respectful manner 5. Offer advice based on experience or knowledge (see jumper5836's post above for an example) Thanks and have a Merry Christmas!

Are they torque to yield bolts? If so, you should replace them, if not you can reuse. What the dealership recommends is irrelevant here.

For reference, these bolts are available at Suncoast Parts for $4.50 each. If you replace all eight bolts, it will cost you the princely sum of $36. How could anybody afford that unless they were subsidized by Obama!!

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Well La Dee Dah Mr. Moneybags McRicherson, III.

Wow... totally didn't think this post would degrade so rapidly... Cost wasn't the issue, it was time. I have no problem paying an extra $50, but I wanted to get the project done this weekend. I am an engineer, and can't imagine why I would need to replace these bolts, but was just wondering why it's recommended by some manufacturers and not others. Also, these porsche recommendations are the same people that say to only change the oil every 15k miles....and IMS is not an issue...

For what it's worth, the previous owner of my car had the brakes replaced twice at two different dealers, and neither one charged for new bolts (but they did charge for a can of brake cleaner), so I think it's safe to say dealers do not believe it's necessary to replace the bolts.

My rule of thumb, if the bolt is torqued correctly and doesn't show signs of damage (rust,wear,threads damage etc.) then I reuse them. Once the bolt is torqued, it is the shear strength of the bolt you are looking at and that is huge. If the bolt is not tighten correctly, it can flex and that can weaken the bolt so it needs to be replaced. As with all things related to safety, it is easier to say replace it to avoid any lawsuits. One of the things to remember about bolts, there have been millions of bolts sent to the US that were marked with an incorrect grade and failed under load. New bolts also carries risks.

That's the beauty of this forum. Everyone gives their opinion, and you can make your own decision based on their comments and your own thoughts. Every now and then we get a troll who comes in here and stirs the pot, but it's typically very civilized. FWIW, my independent mechanic always changes the bolts.

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^^^This^^^...well said Dennis And for those of us that are stuck at the office today...much of the beauty of this forum gives us all a good chuckle

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Troll or not, the dude is right. Bad grammar or not, he is still right. Replacing a bolt that is perfectly fine is NOT cheap insurance. You are actually introducing a component that you are hoping is good, when the old one you know its good.

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About this. Unless they're torque to yield or structurally deficient, it's stupid to replace. Why not replace the calipers, hubs, all brake lines etc etc for "insurance"? Money out of the window.

Since my is not tracked and if they are in good shape, i reuse them.

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Right about what? It's hard to tell exactly what he's trying to say. I interpret his comments as trying to say that it's stupid to replace the bolts because they cost too much, and that only people on welfare would do such a thing (even though those are contradictory statements). As for whether it's good or bad to replace the bolts, I choose to replace them. True, it does put a new component into the system. But I believe that those parts are quality controlled. They are more likely to be mechanically sound than a used part on my opinion. Again, my choice based on the facts at hand is to follow Porsche's recommendation rather than take my chances with a bolt that appears to be okay based on a visual inspection. Worst case - I'm out $36. Everybody here is free to make their own choice and to determine what's right and what's not right. I believe that my choice is right, you believe that your choice is right. C'est la vie!

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The problem is that you can't always tell if a part is structurally deficient based on a visual inspection. What if the bolt was torqued too hard the last time it was installed and it was damaged and weakened? You might not be able to tell until the head snaps off. Everybody is entitled to their own opinion, but I believe it's stupid not to replace them at $4.50 per bolt.

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LOL!!! I don't disagree with you... just funny how that last sentence came out. Based on these discussions, I'm thinking that since I have to pay $700+ for parts for the brakes, I would go ahead and buy new bolts, but in a pinch, if they look good, go ahead and re-use them (unless you are tracking the car). Probably ensure that at least replace them every other rotor replacement. I really don't believe that these bolts are "structural", and would have minimal force applied to them during breaking etc. also, there are 2 bolts per caliper, and you would need to have both of them fail before there is a "catastrophic" failure, so I really don't think it's an issue. It's just interesting how some manufacturers recommend to replace and others don't... you would think that the "better engineered" brakes would be designed to minimize the forces on the bolts, and thus not require replacement... might just be some of that German OCD (I lived there for 4 years).

I heard that not replacing your caliper bolts every 5K miles or three track laps can accelerate IMS bearing failures... WARNING: THE ABOVE STATEMENT IS A TYPE OF HUMOR CALLED SARCASM. IT IS NOT ACTUALLY TRUE

And this is exactly how a myth becomes a fact on this forum. From now on people will refer to the caliper bolts as a must change item, especially is the car is tracked. Yes people are free to make their choice but then to start pushing those opinion on others is not right. When a bolt is over torqued, it will bind when its being removed and the threads will show the damage. The worst things is knowing just enough to convince yourself and others that what you think is right. Those that have enough hand on experience wrenching on cars know what I mean.

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I hear ya. It did sound kind of funny. I suppose the ultimate question is: does Porsche recommend that you change the bolts so that they can sell more bolts, or is there another reason? Your answer to that question will help you determine which way to go!

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Part of me thinks that anyone who believes it, deserves what they get, but I'll put on the idiot warning anyway. Reminds me of the warning sticker on a S&W .380 BG that says pointing the aiming laser at somebody can cause harm...

Its very apparent who the people that actually know what they are talking about and work on their own cars vs those who don't.. why take advise from a guy that doesn't even work on his own car. OP: its not about the money, its really about the principal of why.. Bad info is bad info.. that's all im saying.. oh FYI.. post 3.. that almost makes me an expect because apparently all you have to do is have a high post count to know what your talking about here.. not actual experience.

Never replaced caliper bolts on any car, ever. If old bolt comes out and is not rusted out, it goes back in with some PbBlaster applied to it for lubrication. If part is not broken, I don't replace it. Period.

I reused mine - no corrosion visible and I don't track. No problems so far ( more than a year). I'd be surprised if anyone here had a broken bolt ? If I was tracking a lot I would change with the pads however - cheap -

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I think we need to ask the mods to start a poll and sticky it.... "have you ever had a catastrophic Caliper Bolt Failure (CBF)... lets see if we can get the value of these vehicles to be closer to that of a similar aged PT Cruiser!

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I couldn't agree with you more! That's why I go with the Porsche recommendations! I trust their recommendations more than those of average people who do their own work. I've done plenty of wrenching on my own cars, but unfortunately I can't tell when a bolt needs to be replaced and when it doesn't. That's why I take the advice of the manufacturer. Saying that that the bolts must be changed is nothing new. Porsche has always recommended that. It didn't start here in this thread. Some people follow the recommendation, some don't. It's not really a big deal.

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[Image-only post; no author-written text. Original image references:] https://rennlist.com/forums/images/smilies/smile.gif

well.. lets do the math then.. shall we?? 2002 Pt cruiser MSRP $15000 79k miles on it market sell price.. $3700 http://www.ebay.com/itm/Chrysler-PT-...US_Cars_Trucks 2002 C2 cab MSRP $79000 69k miles on it market sell price, mine, what i paid for it.. $20k cash.. So.. simple math said this.. 2002 PT... depreciation value is at 75.3% where as a 2002 C2 cab has a depreciation value of 74.6% Well i guess you guys are right.. The 996 beats the value of a similar PT cruiser by a whooping 0.7% hahaha Dont make me add the one sold price that was for $5600 or so that had 32k miles on it.. then your similar 996 would be above it!! Better change out them bolts to keep the value up!!! hahaha Really, some of you guys have ZERO common sense what so ever.. makes me wonder how much money your just screw off based on your own ignorance.. its just a freakin car.. no more.. no less

The notion of replacing the bolts popped up on RL over 10 years ago. https://rennlist.com/forums/996-foru...=caliper+bolts I stated I would change with new if tracking the car. I have tracked my car.....run Motul 600 fluid and bleed the brakes before each event, have the GT3 ducts and use PFC 06/01's. I have seen waves of heat come off my calipers after a 25 minute run. For a typical Summer that would be upwards of 32 25 minute sessions......that is some abuse from heat. Like I said I choose to replace mine when I change rotors. I'm perplexed as to why the fight over "my bolt is better than a new bolt". Geebus this is over $36! Who cares do what you feel good with.

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LOL. Do you know what is one of THE best sporty cars when it come to holding value in the last 25 years? DUM DUM DUM, it is a 1987-1993 mustang 5.0. New could be had for $12,000.00 , today average price for 1987 GT is $6,300 . The good condition notch models are selling for almost $10,000.00 and keep going up. 50% residual value after 25 years is pretty damn good. I should have kept mine, I know that now it would be worth at least $2,000.00 more than what I sold it for back in 08.

Merry Christmas everybody!

only thanks to the LsX motor swap... cars are less then 3k lbs and a swap can be done for around $4k or so.. hardly any of them are used as OEM cars.. but i still like them.. and have a 351 blower motor sitting in my shop right gonna in a SN95 in Jan..

This is not about choosing to replace but about have to replace. Just because the bolt gets hotter during tracking, it doesn't meam it needs to be replaced. Besides a wild guess, is there anything scientific that this decision is based on? These bolts will need a lot more heat than what the brakes can ever produce to make them weak or fail. You are afraid of something that doean't exists. Price has nothing to do with this discussion.

I agree that price has nothing to do with the discussion. The bolts are cheap. Personally I have no data that show that the bolts need to be replaced with each brake change. On the other hand, nobody has presented data to me that show that the bolts can be reused. Typically, I wouldn't ask for data on a bolt in an application such as this. My plan would be to reuse the existing bolts. However, Porsche recommends that the bolts be changed. This recommendation is the reason for this thread. So, the question is: why does Porsche recommend this? Do they recommend it to create a revenue stream? Do they recommend it because they have data that suggest that the bolts are weakened either due to heat cycles or perhaps damage from removal and reinsertion? Are they recommending this because these are brake components and they want to "play it safe"? None of us know the answer to this question. Without knowing the answer to the question, we then have to make a choice. We can reuse our bolts, or buy new ones. I don't think it's stupid to reuse existing bolts, and I don't think it's stupid to buy new ones. It comes down to a personal choice. For me personally, I believe that Porsche recommended changing the bolts for a legitimate reason. I don't believe that there's a "bolt conspiracy" or that they just want to sell more bolts. I may be wrong, but I don't know. Therefore, I replace them. For others, they don't want to follow Porsche's recommendation and they reuse their bolts. That's their choice based on their experience and their thoughts about Porsche's recommendation. This isn't a discussion about experience working on cars or not. This isn't a thread about price. It's simply a thread about following Porsche's recommendation, or not following it. To each his own. Merry Christmas!

One thing is sure though.... if for some crazy reason something happens to your brakes which would be cause for either warranty replacement, class action suit, etc etc, and you didn't follow Porsche recommendations, you may be out of luck.

Well there is some point to change the bolts. At least I think so, here is my opinion on this. All assumptions, I have no time to prove these Ok, with the radial brakes, that 996 have, you have longer bolts than the traditonal calibers. Did a little calculations with some guestimate measures for bolts and caliber. Now if the bolts are 110mm long and go thru 90mm caliber to the wheel carrier. Becouse steel and aluminium has diffrent thermal expansion rates, the bolts will strech on every heat cycle. With the numbers above and temperature change of 280c (from 20c to 300c) there will be a 0,2mm strech on the bolt's. It's not much, but it's the same thing if you over torque and loosen the bolt's 1/6 turn's on every heat cycle. You can get these kind of changes only when on track, or very fast twisties in midle of nowhere. I would't compare these bolt's to brake lines. If the bolt's fail, caliber can lock up the wheel. And it's more than likely, that you become the passenger in that car. Just saying.

Can someone post the page where the WSM requires these bolts to be changed?

Factory service manual group4 Running gear.

Thanks. What is group 4? The single asterix is for the screw replacmement note? Where is the double asterix note?

Here is the full page. I think the group 4 is the chapter in work shop manual. For the 2 asterixes, the lower note?

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It shows you which of the two notes to apply to that item.

"Group 4" = Running Gear

Well and there we have it. Porsche does recomends to change them. Weird as I haven't seen this before with other models or makes.

Yes, Porsche does recommend it.

I sure hope "weldingmachine" posts in more threads. This guy is great and probably made this one of my all time favorite top 10 threads.

This is discussed in this thread: https://rennlist.com/forums/996-foru...per-bolts.html Weird thing is I got my bolts from a dealer, and they didn't look very special to me to justify the $6 per bolt price.

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It was certainly an entertaining thread, in many ways.

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The recommendation began with the brake calipers on the front axle of the 993, the rears you could re-use.

From reading past threads, there appears that the new bolt threads are coated. That would explain the replacement of the bolt since coating will effect torque values and the ability to remove them in the future.

Ya.... I never expected my original question to elicit 60 responses (I was hoping for 1). Hope everyone had a Merry Christmas.... I got new caliper bolts in my stocking!

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Nonsense. They all come out if the pipe is long enough.

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Working on one's car is no sign one knows what he's doing. In my case, I used to work on my cars, used to do the brakes on my cars, including my Boxster. (This last time I had the front brakes done at the dealer because I had no spare time, no place to work on my car.) When I started working on my cars I had good mechanics handy who advised me of the *proper* technique for auto repair. Even then back in the day of brake drums the rule was replace everything. Not only the shoes, but the wheel cylinders, and all the springs and retainers. My mechanic advisers told me of horror stories about a spring retainer failing and the damage this could and did cause to the rest of the brake hardware and the drum causing a real mess. It only takes one of these to erase any profit from a number brake jobs that were done and the hardware not replaced and the savings passed on to the customer. The bolts are not stretch bolts. But they exist in a very critical location. If the car doesn't go that's not so bad relatively speaking. If the car won't stop... well, just look at what Toyota is going through with just a handful of cars with this symptom and apparently because Toyota can't prove a negative it is going to have to pay perhaps nearly a $1B dollars in claims. The bolts are to be installed dry, with no thread lube. The bolt threads have some surface treatment that acts as a lube for when the bolts are installed. Once removed this lubricant is gone. If the threads gall upon reuse the calipers can be ruined. The bolts are a lot cheaper than the calipers. The bolts are the sacrificial items in this instance. Unless you prefer to replace calipers. Sure many get away with not replacing the bolts. But there are quite substantial differences in where one lives and drives to make one size or one rule fit all. For example both of my Porsches are on their original coils. I happen to live and drive in an area that sees less humidity and rain fall than other regions. The techs at the dealers in my area tell me coil replacement is very rare. However, I know from my online reading that there are regions of the world where coil life is it seems measured in months rather than years or thousands of miles let alone a decade and hundreds of thousands of miles. I still have a lot of faith in Porsche and in Porsche knowing what is best for its cars, how they are to be repaired. Don't kid yourself that Porsche is after making money on bolt replacement. If Porsche felt that replacement was not necessary it would drop that replace the bolts recommendation in a NY second. It costs Porsche some amount of money to stock those bolts, catalog them, document their replacement, etc. Probably costs Porsche as much money as it makes from the sale of those bolts. Understand, it is your car and you can choose to service it anyway you want. Where I have a problem is when someone comes up and says because I've done this and gotten away with it -- so far -- it is ok for everyone to do it. This is no different than someone who has smoked all his life with no apparent ill effects stating that it is ok to smoke because he did it and survived. IOWs, it is not ok to manage to avoid trouble or complications by accident and then turn around and expect everyone else to have the same luck as you.

For my own peace of mind I replace all of mine every other brake job. I hold on to 4/5 of the old cycled out bolts just in case I or a friend during a track day event needs one. you never know!!

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haha.. what complete waste of space with your "theory" "Im avoiding trouble by not replacing a bolt and im giving "bad" info because its not the same thing that a company says to do because they do profit from it. You have no idea about the true cost of reoccurring revenue apparently. You think a bolt is "important" but there are far more important items that never get replaced..or ever checked... ever replace your cooling rubber tube underneath your car??? funny how that is used every time 100% your car is running,always has "pressure".. if it fails, you are far more licky to tear something up and be stuck on the road somewhere and yet "Porsche" didn't even have the thought process to cover it up with stupid plastic covering they put under everything else.. so is that "ok"? not really. but you don't think twice about it.. If im lucky, so be it.. its funny how others are :lucky" too and not one person yet has said they didn't replace it and it failed. All you have is some guy telling you ghost stories about "one time at band camp" You and few other have a problem.. this is true.. is called the lack of common sense..Which seem to run a premium on this site and the more people post "what they heard" stories, the more it scares people into think there is a problem when there really isnt one.

Macsrer is very good at writing long winded sotries with half fabricated theories. The worst part is that those who know less than him, and there are many here, will beleive it. Replacing a perfectly good wheel cyclinder during a routine brake job is nothing more than a money grab. I had springs break and they only thing happened was noise that let me know something happened. The way I see it is that Macster has very little self confidence so he relies on mechanics for info. If you really were a DIY-er, you wouldn't be going asking mechanics all the time for directions.

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Although there seems to be a lot of stupid posts(more so lately), I also have a hard time holding my tongue at times. You just gotta let go sometimes and sit back and laugh at some of this. It seems like you've "been around the block" and you're probably wasting a lot of your time here with some of these amateur like threads. If you don't know already about Renntech forum, I'd like to recommend it to you as you'll probably find it more informative(and possibly enlightening).

The "weldingmachine" drives a cab? Sir, you just lost all credibilty. This place gets more and more entertaining. In Macs defense, the "weldingmachine" hasnt posted any of his creds about how hes replacing JR on the forum as the resident expert. Now lets see you drop that engine.

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Yep, been around around a time or two.. I appropriate the site info, been looking for more informative site with DIY info. I don't know everything about Porsche, but its certainly keep me from doing it and using good common sense.

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haha.. I do indeed have a cab.. so that means what?? Again, is one car..It has PSS10 as will as a few other "mods" Engine drop is a piece of cake when everything is attached.. you doing it doesn't impress me much..other then its miles what i expert from most here. I don't really feel the need to go on about me and "what i can do or did". I don't want to pull it and and show you.. you seem like you might get your feelings hurt and never recover from it...