I'm finally getting the rear brakes put together on my car. Got the lines put into the calipers, and looked up torque values for the caliper bolts. Of course, while doing that I noticed that the manual (Haynes) says to replace the caliper bolts with new ones. Verified it with the Volvo manual, then swore a lot, went inside and started looking online for bolts.

Before we get too far into this, I'm probably going to replace them with new bolts. Going against the manufacturer's recommendation scares me, especially with something as safety-related as brakes.

That being said, the purpose of this post is to try to understand just why it is that Volvo would recommend replacing them. They seem fairly heavy duty, and the 48ft-lb torque rating (if I remember correctly) seems like far too low to be a torque-to-yield value. Only thing I can some up with is that the new ones (like these: https://www.fcpeuro.com/products/volvo-brake-caliper-bolt-240-244-245-genuine-volvo-947328) seems to have a red spot that I'm guessing is some sort of high-temp thread locker. I feel like some high-temp loctite could replace that. Does that sound right? Am I missing something?

Note that new OE Volvo rotors come with new caliper bolts. Doesn't mean you "have" to replace the bolts, but it certainly is easier! And the OE rotors are cheaper than most aftermarket. Yes, they are made in China, and no I haven't had any issues with them!

Thanks, everyone. Sounds like the overwhelming vote is that the originals are just as good as if not better than any replacements. I'll be putting the old ones back on.

I have never replaced them in almost 30 years of driving bricks. Red lock tight is probably a good idea, but I have yet to see one loosen that was torqued properly on the reinstall. Never seen a failure.

I replace the left one with the right one and the right one with the left one. ;)
--
82 242 6.2L coming...; '15 Honda Fit

If I don't replace them, then what holds the calipers on? ;)

Seriously, OE Volvo hardware is usually pretty darn good stuff. I would be more leary of the quality of the replacement than that of the original.

I agree with you on this Chris!

The ones that were in there have been tried and tested to be good.

After-market may not be as good as post-market!

Wait a minute isn't that the same junkyard items?

I have pulled a lot of good stuff from junkyard. Buying After-market always scares me into a caution mode!

That's probably why I put my olds ones back in and torqued them properly!

Any thread gumbo I put on is purely optional.


My method is Basic. If they were in there tight when you took out they should go back the same as torque holds them in. IMO the torque values are reasonable low for the diameters of these bolts.
These bolts are being used to resist shear more than a tension force.

If they seemed to be not as tight as you thought they should have been when you removed them. You should look for shine or damage to the smooth diameter of the bolt or to the hole in the caliper body.
This you should know by the feel of the threads going together.
In others words don't put anything together that seems a little "shaky" or excessively tight in terms of being a good mechanical assembly.

Any Two "Mating" parts can have variances. They can join with one at a high end or low end of any manufacturing tolerances and still be with designed fits. There are plenty of other caliper bolts on the car to compare to if in doubt of a damaged one.


Assembly lines strive for speed. They don't get paid for second guessing what's pright or wrong. That's "suppose" to be taking care of in the quality controls departments.

By putting stuff on the threads it is a "back up" or " stop gap" for assembly line descrepencies.
Take either thread locker or stop leak it covers the manufacturers buns and who can argue with that.

The costs are minimal and it starts saving them money right away in the overall picture.

During the nineties onward GM put stop leak in their coolant during assembly just to get them off the assembly line. They let their dealers deal with any issues under a warranty hassle programs.

Take either one, a thread locker or stop leak that covers the manufacturers buns!
The costs are minimal and it starts saving them money in the overall picture let alone insurance cost or liabilities.
Another reason I will never want a new "overly" advertised car that's surely going to depreciate when some ink hits the papers!
We all know these routines well!

I figure I'm a better assembler as I don't strive for speed!
My car is not as high up as an airplane or nearly as fast!
Cars are really low tech by comparison of systems. That is, until they try to make them idiot proof because there are idiots drivers abound!

Our 240 Volvo's do have a redundent brake system and spare tires. No spare engines on board though. (:-(
Some new cars (Mercedes Benz/Smart Car) don't even carry a spare tire! Two different sizes tires from front to rear. Real smart, huh? Who knows what that "smart car" uses for a brake system?

I personally use "tested" caliper bolts and refresh the thread locker, if I have some? (:)
I have not worried about it.
If my brakes ever start squealing or vibrate I will listen and look!
WORN down or glazed pads are more likely to cause a problem. IMHO

I have never replaced a bolt, even though, I have read the recommendations from manuals.
They have to put the recommendation statements in there to remove themselves from their own liability.

It is the world we live in! One of too many pointing fingers that don't bend enough at themselves!

Phil

I don't know how many times I've had the calipers off a Volvo, but I have never replaced the caliper bolts, and never had a problem.

Greg

Tatra Mike said what I would have said, but said it better. Same with me.
--
Art Benstein near Baltimore

What do you call a dinosaur with an extensive vocabulary? A thesaurus.

Okay, to start with, I'm pretty much a follow the book kind of guy. I've got the Bentley, Chilton (worthless) and full factory manual set. In my opinion the more manuals the better.

One of my 240s has had 4 brake jobs in 25 years and I've never replaced them. I give them a good visual inspection with a magnifying glass, apply some red Locktite and reinstall to the specified torque.

Would I do the same on a airplane I'm working on, no!

Now, this is definitely a judgment call. I don't recommend you do the same unless you feel it meets your safety standards. My rationale is that manufacturers make this type of recommendation on the advice of their attorneys.

Some bolts are replacement items such a cylinder head bolts as they stretch when installed.

Regards,

Tatra Mike
Seattle, Washington

1985 244 "Alfsen" (wife's car - the good one)
1984 245 "Buster" (the kid's car, now sold)
1985 245 "Cosmo" (parts car, sold off for move to WA)
1985 245 "Daisy" (back seat down, full of tools, the work truck)
1985 245 "Earl (CA vehicle 'retirement' program)
1985 244 "Junker 1"(Awaiting cannibalization)

Can you tell I prefer the 1985 model 240? Better headlights than the plastic 1986+ and nicer belt adjustments than the 1984s and earlier!