Caliper Bolts
#16
I don't believe these are stretch bolts. Just hardened steel bolts which come with pre applied threadlocker. Stretch bolts are more commonly used on cylinder heads to ensure fairly consistent torque when applied with pneumatic tools.
Lexus does recommend new ones so if you don;t mind the cost replace em. I have 50k miles on my old ones since they were reinstalled. So far I haven't crashed off a cliff into the ocean.
Lexus does recommend new ones so if you don;t mind the cost replace em. I have 50k miles on my old ones since they were reinstalled. So far I haven't crashed off a cliff into the ocean.
#18
It is a part of the car you use often...your brakes. Why screw around for 25 bucks. It may have nothing to do with brake pulsation but that is a pet peave of mine I would rather not deal with and avoid.
#19
From Sewell, for all four wheels with the CL discount, $35.60 or $4.45 per bolt... I happen to be paying an additional $22.67 for two day shipping so I can get them for this weekend, so its costing me $58.27 for the eight bolts... Since I'm doing both front wheel bearings, I'm going to mic out the front rotors and make sure they're in spec. If not, I'll replace them at the same time and throw new pads on...
I found this article that explains the concept of a stretch bolt very well... If the bolts bolted in from the side, like on the 1st gen LS400, it would be the shear strength of the bolts that would be the predominant factor. Since these bolts bolt in from the back of the caliper, every time you apply the brakes, the bolts have tension being put on them length-wise. Now that I understand how they're being utilized, I'll be installing the new ones this weekend when I reassemble.
http://www.gomog.com/allmorgan/stretchbolts.html
I found this article that explains the concept of a stretch bolt very well... If the bolts bolted in from the side, like on the 1st gen LS400, it would be the shear strength of the bolts that would be the predominant factor. Since these bolts bolt in from the back of the caliper, every time you apply the brakes, the bolts have tension being put on them length-wise. Now that I understand how they're being utilized, I'll be installing the new ones this weekend when I reassemble.
http://www.gomog.com/allmorgan/stretchbolts.html
#21
#22
The bolts aren't reusable since they are much softer than the high tensile ones like those found on Toyota SUV's. The issue is the A-arms/suspension components onto which the calipers are attached on the LS430 are made of aluminum (weight savings, corrosion resistance), which is a lot softer than the steel components on the other toyotas (and for that, just about every car other than high-end luxury ones like BMW, Audi, etc.). So the bolts used for the calipers have to be much softer so they don't strip the aluminum before reaching proper torque. There's no way the dealer will reuse the bolts. Let's say they did, and you drove off the lot and the caliper bolts sheared when you hit the brakes hard, causing you to crash. There would be major liability issues on the dealer's side. OTOH, if you reuse the bolts and the same thing happens, you only have yourself to blame. At $5 each bolt, it's peanuts compared to whatever brake job you're doing. That's $10/caliper or $20 per axle, less than what the dealer charges each time for "misc shop supplies" like rags, gloves, and cleaning solvents! I reused a simple brake hose bracket bolt on my LX like 4x (torque on it was like 25 ft-lbs) and the thing sheared off when I tried to torque it to spec the 5th time...had to drill the bolt and use one of those extractors to remove it.
#23
Here's a quote from Mitchell DIY pertaining to the front calipers on the LS430... The operative words being "2 new bolts"...
INSTALL DISC BRAKE CYLINDER ASSY LH Install the caliper with the 2 new bolts. Torque: 110 N.m (1,122 kgf.cm, 81 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
INSTALL DISC BRAKE CYLINDER ASSY LH Install the caliper with the 2 new bolts. Torque: 110 N.m (1,122 kgf.cm, 81 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
#24
To each his own. As I said I'm almost 50k miles into my resuse of the bolts and no problem. Sure anythings possible but suggesting the most extreme of fringe scenarios as a possible outcome is just silly.
I think I am 100000x more like to have a tire blowout at highway speeds that a sheered caliper bolt is going to cause a serious accident. I'd rather buy a slightly better tire.
I think I am 100000x more like to have a tire blowout at highway speeds that a sheered caliper bolt is going to cause a serious accident. I'd rather buy a slightly better tire.
#26
Here's a quote from Mitchell DIY pertaining to the front calipers on the LS430... The operative words being "2 new bolts"...
INSTALL DISC BRAKE CYLINDER ASSY LH Install the caliper with the 2 new bolts. Torque: 110 N.m (1,122 kgf.cm, 81 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
INSTALL DISC BRAKE CYLINDER ASSY LH Install the caliper with the 2 new bolts. Torque: 110 N.m (1,122 kgf.cm, 81 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
#29
Well, this is certainly confusing... Below are three quotes from Mitchell online. One states 81 ft. lbs, the other two state 58 ft. lbs... Below that are two exploded views of the front and rear suspension for the 2005 LS430 off of AllData... They both state 58 ft lbs... What is the copyright date of the repair manuals you have? I wonder if the spec was changed?
Mitchell:
INSTALL DISC BRAKE CYLINDER ASSY LH Install the caliper with the 2 new bolts. Torque: 110 N.m (1,122 kgf.cm, 81 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
Mitchell:
INSTALL DISC BRAKE CYLINDER ASSY REAR LH Install the disc brake cylinder assy rear with 2 new bolts. Torque: 78 N.m (800 kgf.cm, 58 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
Mitchell:
NOTE:Brake caliper bolts can not be reused. Do not twist the brake hose. Make sure that no damage and no foreign matter is attached on the bolts. Sliding the brake caliper outer side of the vehicle and tighten bolt A first then bolt B. Torque: 78 N.m (800 kgf.cm, 58 ft.lbf) NOTEo not over tighten the bolts.
Alldata Exploded Views Front & Rear (2005 LS430) 58 ft. lbs.
Mitchell:
INSTALL DISC BRAKE CYLINDER ASSY LH Install the caliper with the 2 new bolts. Torque: 110 N.m (1,122 kgf.cm, 81 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
Mitchell:
INSTALL DISC BRAKE CYLINDER ASSY REAR LH Install the disc brake cylinder assy rear with 2 new bolts. Torque: 78 N.m (800 kgf.cm, 58 ft.lbf) NOTE:Since the bolted portion is an aluminum knuckle, keep it clean and avoid over tightening. Pull the disc brake cylinder assy toward the outside of the vehicle to remove any play between the pin and knuckle hole. From this position tighten bolt 1 and 2. Always follow these directions when installing.
Mitchell:
NOTE:Brake caliper bolts can not be reused. Do not twist the brake hose. Make sure that no damage and no foreign matter is attached on the bolts. Sliding the brake caliper outer side of the vehicle and tighten bolt A first then bolt B. Torque: 78 N.m (800 kgf.cm, 58 ft.lbf) NOTEo not over tighten the bolts.
Alldata Exploded Views Front & Rear (2005 LS430) 58 ft. lbs.
#30
I have the 2005 LS factory manuals...front caliper is 81 ft-lbs, rear is 58 ft-lbs. Not only that, you have to pull the caliper out towards the outside of the vehicle to remove as much play as possible, then do the final torque on the bottom bolt first, then the top (in that order). This goes for both calipers. Do not overtighten, as they bolt onto an aluminum knuckle.