PotatoMafia
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- #1
Does anyone know the torque specs for the front and rear rotor mounting assembly and the caliper assembly?
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Torque specs for front and rear brake rotors / assemblys
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PotatoMafia
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- #3
are those brake bolts really 1 time use or send em with blue loctite?
if so can anyone reference the part numbers for them?
if so can anyone reference the part numbers for them?
Thraxbert
Well-Known Member
The bolts marked one-time-use are torque-to-yield (TTY) fasteners. I would do some Google searching on this topic and decide your level of risk for yourself.
Suffice it to say: once removed, they will never hold at the correct level of torque again, as they've been permanently stretched by the tightening process. TTY bolts improve the consistency and durability of the clamping force, and require fewer bolts in a given area to secure XYZ thing. They also require less maintenance, because you don't have to retorque them -- the stretchiness/springiness/yield of a TTY bolt takes care of that problem for you. If things shift, stretch, or compress a little bit, a TTY bolt will still hold at the same torque.
But the downside is that the yield/stretching is permanent and weakens the bolt. It cannot again reach the specified torque or holding power. Retorquing it to spec could cause it to break, or it could shear in service, or the clamping force could fatigue out and come loose in service.
Do lots of people reuse TTY bolts? Yes they do. Should they? No. But can they? Maybe, maybe not. It depends on the application. You alone must be the judge.
Suffice it to say: once removed, they will never hold at the correct level of torque again, as they've been permanently stretched by the tightening process. TTY bolts improve the consistency and durability of the clamping force, and require fewer bolts in a given area to secure XYZ thing. They also require less maintenance, because you don't have to retorque them -- the stretchiness/springiness/yield of a TTY bolt takes care of that problem for you. If things shift, stretch, or compress a little bit, a TTY bolt will still hold at the same torque.
But the downside is that the yield/stretching is permanent and weakens the bolt. It cannot again reach the specified torque or holding power. Retorquing it to spec could cause it to break, or it could shear in service, or the clamping force could fatigue out and come loose in service.
Do lots of people reuse TTY bolts? Yes they do. Should they? No. But can they? Maybe, maybe not. It depends on the application. You alone must be the judge.
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PotatoMafia
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- #5
just trying to make sure i get the right part, is 90118WA651 the correct part number for the rear caliper bolt that needs to be torqued to 110NM?
Tsuki8
Well-Known Member
Very nice, which site is that?As far as I am aware:
90118-WA630 x2 for front caliper to hub (70 lb-ft), and 90118-WA651 x2 for rear.
Much easier to use than the clunky new Toyota ones.
Thraxbert
Well-Known Member
https://partsouq.com/en/catalog/gen...bN35ib2Nbcm4Sc0JIAAAAAgGepZw==$&vid=0&cid=&q=
Much better than Toyota's parts diagrams, indeed. I discovered this website a few years ago when restoring a Suzuki Jimny, and I've been using it for my all my cars ever since. The Toyota official diagrams are especially vague and poor, and sometimes the dealer-provided parts websites don't even agree with Toyota.com. And sometimes it's Toyota.com that's wrong! It's madness.
MoreIceTea
Well-Known Member
As far as I am aware:
90118-WA630 x2 for front caliper to hub (70 lb-ft), and 90118-WA651 x2 for rear.
Huge thanks for confirming the part number! Toyota did a terrible job on marking this bolt as #7 on their diagram, with a confusing description. I was suspecting 90118WA651 is the right part number but struggling to find anywhere clearly points it out.
tracer bullet
Well-Known Member
Edit: I see 17Nm in the top of the first drawing posted in post #2. Never mind the below unless you're really bored.
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BMW TIS shows 17Nm for rear caliper, aluminum, painted (oddly specific, I'd think it just matters aluminum or cast iron, but unpainted aluminum is the same value). I would reasonably think the front is the same.
My approach is basically an 1/8 turn or so past finger tight. I know to go light, and my method seems to work (no leaks, no broken bleeders or stripped calipers) but this is the TIS on it. I haven't tried my 1/4" low force torque wrench on it but this feels kind of high to me. Maybe not, the oil drain plug is 25Nm, it's not too bad and this is less. I'd still err on the low side. Finger tight for me is using the 1/4" ratchet, twisting with like 3 fingers way up at the head of it and off the handle.
I know the question was > a year ago but if anyone wants a #, that's it per BMW anyhow.
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