Brake Caliper mounting bolts! Replace them when removed. Alert Alert Alert (1 Viewer)

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Here is my experience with toyota:
I fix my dad's hilux LN 106 made in 1990 and it still has same caliper bolts and never used any thread lockers.

When I took the truck to get front leafs springs done, you won't believe what the guy did to the front brake hoses. He NEVER disconnected the brakes (hoses or caliper from mounting) and simply raised the truck to release the tension on the leafs springs. That made the hose to stretch almost 100% percent. I was small and had no idea, but nothing happened to hoses and it got replaced after 12 years due to being old.

Newer toyota's are not as good as the ones made back then I guess.

That sounds like you didn't have the proper brake hoses for the truck.
 
Went out of town to visit some family over the weekend, there was a rattling sound coming from the rear when I would hit bumps in the road, etc. I was worried maybe some of the internal hardware for the parking brake was loose, missing a spring or something. Nope, drivers side rear lower caliper bolt simply was not there, poof. I blame it on the crap ass roads in Michigan. I replace the bolt with grade 8 12mmx1.25.25mm. I would advise folks to either replace these, their cheap, or really hammer down on the ratchet with a rubber mallet or something. I ended up replacing the rear rotors while I was at it and readjust and lube of parking brake tidbits.
 
Went out of town to visit some family over the weekend, there was a rattling sound coming from the rear when I would hit bumps in the road, etc. I was worried maybe some of the internal hardware for the parking brake was loose, missing a spring or something. Nope, drivers side rear lower caliper bolt simply was not there, poof. I blame it on the crap ass roads in Michigan. I replace the bolt with grade 8 12mmx1.25.25mm. I would advise folks to either replace these, their cheap, or really hammer down on the ratchet with a rubber mallet or something. I ended up replacing the rear rotors while I was at it and readjust and lube of parking brake tidbits.
Mine has played the same dirty trick on me before. It kept making unhappy noises until I tried to brake in reverse, at which point the whole caliper rotated and locked up against the wheel.
 
I said it once and I’ll say it again: blue loctite all caliper mounting bolts.
I think FSM calls for new bolts every time. Ever since the last time this ruined my day, I now carry two spares with me
 
After some review, I'm almost certain the threadlocker is actually a microcapsule suspension that 'activates' under torque by breaking the particles and mixing. They define them as non-reusable for that reason, then
 
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After some review, I'm almost certain the threadlocker is actually a microcapsule suspension that 'activates' under torque by breaking the particles and mixing. They define them as non-refundable for that reason, then
That's really interesting. Do you have a link to any info on that? I'd love to read up on it. Sounds better than most of the pre-applied thread lock compounds that are commonly used.
 
After some review, I'm almost certain the threadlocker is actually a microcapsule suspension that 'activates' under torque by breaking the particles and mixing. They define them as non-refundable for that reason, then


Loctite 290?
 
I think FSM calls for new bolts every time. Ever since the last time this ruined my day, I now carry two spares with me

I can't find this in the FSM. Can you please post the page that says this?
This is not in the TIS or hard copy books of the 100 series FSM, in any year I've looked at.

As stated in OP; This was a change made in the 200 series in 2008 FSM.

I've both the 100 & 200 series new front OEM bolts on hand. They are appear the same. Except for the red thread seal on the 200 series bolt (pictured in OP). Toyota also reduced torque in 200 series for the caliper bolt.
100 series ft-lbf: Frt 90, rear 76.
200 series ft-lbf: frt 76, rear 70.

So why so did factory make the changes?
IMHO Toyota saw an issue in the 100 series that was in-part what prompted the change.
What may have been the issue? Stretching of the bolt.
Why is new front bolt coated; Add security.
Why reduce torque. To compensate for lube (sealer) on threads of new bolt. Using 20% reduce torque as rule of thumb when threads are lubed, they actually increased torque.

In mud, over the years, we've seen/reports of caliper bolt falling out numerous times over the years. Mud is a small sampling of the global 100 fleet, dealerships would see much more and held accountable. Could it be we've just kept forgetting to torque the bolts, perhaps. But then why the change in the 200 series for the same bolt.

I'm may be totally off base in this alert. But with brakes it's better safe than sorry. I'm now painting/marking bolts after torquing. If ever caliper bolt was painted, and we saw it fall out. Well then we'd know. The fleet is aging and for few pennies, it can't hurt.

Notes:
I've no rear 200 series bolts on hand, nor does picture at PQ show it coated.

200 series also has crawl control. This uses ABS to control the crawl. So caliper takes a real pounding. But 100 series has ABS, that gives pounds to the calipers also. Which ABS is used more, depends on driver. But crawl would be for longer duration.
 
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I can't find this in the FSM. Can you please post the page that says this?
Thanks for calling this out: I think I read it wrong - its the gasket for the brake lines that need to replaced (indicated by a diamond sign).
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This is not in the TIS or hard copy books of the 100 series FSM, in any year I've looked at.

As stated in OP; This was a change made in the 200 series in 2008 FSM.

I've both the 100 & 200 series new front OEM bolts on hand. They are appear the same. Except for the red thread seal on the 200 series bolt (pictured in OP). Toyota also reduced torque in 200 series for the caliper bolt.
100 series ft-lbf: Frt 90, rear 76.
200 series ft-lbf: frt 76, rear 70.

So why so did factory make the changes?
IMHO Toyota saw an issue in the 100 series that was in-part what prompted the change.
What may have been the issue? Stretching of the bolt.
Why is new front bolt coated; Add security.
Why reduce torque. To compensate for lube (sealer) on threads of new bolt. Using 20% reduce torque as rule of thumb when threads are lubed, they actually increased torque.

In mud, over the years, we've seen/reports of caliper bolt falling out numerous times over the years. Mud is a small sampling of the global 100 fleet, dealerships would see much more and held accountable. Could it be we've just been keep forgetting to torque the bolts, perhaps. But then why the change in the 200 series for the same bolt.

I'm may be totally off base in this alert. But with brakes it's better safe than sorry. I'm now painting/marking bolts after torquing. If ever caliper bolt was painted, and we saw it fall out. Well then we'd know. The fleet is aging and for few pennies, it can't hurt.

Notes:
I've no rear 200 series bolts on hand, nor does picture at PQ show it coated.

200 series also has crawl control. This uses ABS to control the crawl. So caliper takes a real pounding. But 100 series has ABS, that gives pounds to the calipers also. Which ABS is used more, depends on driver. But crawl would be for longer duration.
I think it is sound advice. I’d hate to be driving through mountains and lose a caliper. We’re talking about the price of a cheeseburger for peace of mind and safety.
 
I only replace those if:
A. FSM calls for it (on BMW seems like _everything_ is one-time this days)
B. Someone was working on it before me (stretched bolt)

If no call from FSM and no one touched it - I just torque to factory specs and don't worry about it.
 
OK, so maybe this isn't the case. So much for being certain. At least every example of these microsphere based threadlockers looks like a thickish paste on the threads. The 2010 dodge 3500 brakes I just put on my 80 use caliper bolts with this stuff, and are "single use only" supposedly. I just assumed the argument for the hundy calipers was the same.

Edit: like this
Amazon product ASIN B07CJP5KHT
 

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