I had my car aligned today at a non-dealership tire shop. I received the news from them that the rear pads need replacement, that the rotors were near minimal specs and the front were questionable.
I have always had my brakes and rotors replaced/resurfaced at Infiniti (I am now at 87K and frankly don't remember where I am with brakes and rotors in terms of replacement). My question is whether the '92Q is finicky about the brakes and rotors needing to be OEM or whether I should consider saving some dollars or receiving more for my dollar with non-Infiniti parts (and, if so, which brands are recommended and which are to be spurned)?
ThanksKen K
'92 Q45 brake and rotor question
A quick search for rotors turned up this in-depth discussion on brake pads and rotors for a 90 Q. Scroll down for a few posts from Q45Tech about the pad/pad material. Also, a few good posts/discussions on slotted rotors can be found in the Infiniti General, try a search there on rotors as well.
Happy reading.
<hint> Metal Master pads and slotted rotors from Joe
Happy reading.
<hint> Metal Master pads and slotted rotors from Joe
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Q45tech
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- Posts: 14296
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
the 90-96Q all use the same calipers and rotors. The were at least 3 different part numbers for the front pads and numerous tiny tweeks to compounds withouut parts number changes.
The rears kept the same number thoughout but compounds changed over the 6 years.
For a NORMAL driver [who doesn't like surprises] and who sees cold weather [below 40F] the oem pads and their 600F friction limit should work fine.Metal Master pads raise the top temperatue friction vs pedal pressure by 100F but lose friction cold [have to push harder].
Women do not have the same leg strength on average as men, therefore factory pads are set for 10-40 pounds of pedal pressure for even a single panic stop........till the pads reach 600F.
The rears kept the same number thoughout but compounds changed over the 6 years.
For a NORMAL driver [who doesn't like surprises] and who sees cold weather [below 40F] the oem pads and their 600F friction limit should work fine.Metal Master pads raise the top temperatue friction vs pedal pressure by 100F but lose friction cold [have to push harder].
Women do not have the same leg strength on average as men, therefore factory pads are set for 10-40 pounds of pedal pressure for even a single panic stop........till the pads reach 600F.
q45tech,
Thanks for the info. After reading other threads that I was directed to I found your comments on OEM pads and will use them.
In one post you mention that your shop offers three different rotors: "factory, brembo, and powerstop drilled", to be exact.
Can you tell me what the advantages/disadvantages would be of these three? (I suspect that the factory rotors will be fine but I am interested to know what I could gain, if anything, from the others. My driving is city and highway, I am not particularly hard on the brakes [which amazed me when I found that the brake pads wore out so quickly when I first purchased the car--that has improved with subsequent pad materials], and the temperature in Fresno, CA varies from the 30's in the winter to 105 in the summer.)
Two quick questions: (I am going to check with the dealer as to whether they will mount parts that they do not supply, so that I can order from infinitipartsusa.com to take advantage of their discount.) 1, do I need to order a shim kit, i.e., do these need to be replaced or are they relative lifetime parts? 2, my front rotors are 1.030 and 1.045 and the rears are .310 each. Is there enough metal left to resurface or will these need to be replaced?
ThanksKen K
Thanks for the info. After reading other threads that I was directed to I found your comments on OEM pads and will use them.
In one post you mention that your shop offers three different rotors: "factory, brembo, and powerstop drilled", to be exact.
Can you tell me what the advantages/disadvantages would be of these three? (I suspect that the factory rotors will be fine but I am interested to know what I could gain, if anything, from the others. My driving is city and highway, I am not particularly hard on the brakes [which amazed me when I found that the brake pads wore out so quickly when I first purchased the car--that has improved with subsequent pad materials], and the temperature in Fresno, CA varies from the 30's in the winter to 105 in the summer.)
Two quick questions: (I am going to check with the dealer as to whether they will mount parts that they do not supply, so that I can order from infinitipartsusa.com to take advantage of their discount.) 1, do I need to order a shim kit, i.e., do these need to be replaced or are they relative lifetime parts? 2, my front rotors are 1.030 and 1.045 and the rears are .310 each. Is there enough metal left to resurface or will these need to be replaced?
ThanksKen K
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Finding a high priced rotors is easy as the dealers markup the cost roughly equal to Powerstop.
There are half a dozen companies that offer us wholesale priced rotors say in the under $50 each range........that we can sell for $75-80 each.........unfortunately the quality and weight and design varies significantly.
Those listed are what we use and what seems to work about equally.
Things that are advertised on ebay may be unsuitable for those that want as factory quality.
You can always purchase defects and the lower the prices the higher the chances.
I have bought some really bad quality rotors before I started comparing them visually to oem and weighing and measuring the important parameters and learning how they cheat to sell a low priced product.
There are half a dozen companies that offer us wholesale priced rotors say in the under $50 each range........that we can sell for $75-80 each.........unfortunately the quality and weight and design varies significantly.
Those listed are what we use and what seems to work about equally.
Things that are advertised on ebay may be unsuitable for those that want as factory quality.
You can always purchase defects and the lower the prices the higher the chances.
I have bought some really bad quality rotors before I started comparing them visually to oem and weighing and measuring the important parameters and learning how they cheat to sell a low priced product.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
"maximize the value of the dollars spent..."What does that mean? What are your value definitions?
In real life a 10% improvement may mean doubling the price unforunately it doesn't work in the downward situation.
Why we always recommend that factory parts be purchased especially when you can get a 25% discount from this sites sponsors. It not worth the chance in experimenting.
We know that PowerStop is a viable quality alternative for those that want drilled rotors.
In real life a 10% improvement may mean doubling the price unforunately it doesn't work in the downward situation.
Why we always recommend that factory parts be purchased especially when you can get a 25% discount from this sites sponsors. It not worth the chance in experimenting.
We know that PowerStop is a viable quality alternative for those that want drilled rotors.
"maximize the value of the dollars spent..."What does that mean?
It means that I do not want to waste dollars spent pursuing performance promises that are not true, which is why I had sought advice about the rotor replacement. As stated, I have no problem purchasing Infiniti replacement parts; the question is whether I would gain anything by purchasing aftermarket products and I gather from your advice that there is nothing of great value to be had in the realm of brake pads and rotors.
Many thanks for your help,Ken K
It means that I do not want to waste dollars spent pursuing performance promises that are not true, which is why I had sought advice about the rotor replacement. As stated, I have no problem purchasing Infiniti replacement parts; the question is whether I would gain anything by purchasing aftermarket products and I gather from your advice that there is nothing of great value to be had in the realm of brake pads and rotors.
Many thanks for your help,Ken K
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Generally to increase the rotor weight [besides using denser iron] manufacturers thicken the metal to air vent ratio.
The factory rotor has 9mm metal , 10mm air space and 9 mm metal.........some aftermarkets have 9.7mm metal and 8.6 mm air space............some cheapo aftermarkets have 8.6 mm metal and 10.8 mm air space.
You must weight and measure to know what you are getting.
Half a pound [225 grams] [3%] is significant as that may translate to a 25-35F temperature difference in aggressive stopping.
On single stop 60-80 mph decelerations there will be no change in stopping distances from the worst to the best rotors, assumming they are both [all] bedded and equally trued......unless the rotor suface metals have a difference in friction coefficients [unlikely and very small].
The pads will vary based on the pedal pressure vs friction coefficient...........best to worst probably no more than 25 feet based on 129 feet for oem rotor,pads and oem soft tires [170 tread wear index.
Typical 300-400 treadwear tires probably don't add much more than 10-15 feet in DRY stopping distances at 100F ambient and no more than 15-20 feet at 60F...............20-25 feet at 32F.
Correlations from Tire Rack 50-zero braking test - Pilot Sport Cup vs Pilot H4 in 225 vs RSA and worse tires 78>87>100 feet.
Unfortunately no 78 feet tires are available in the 15" size anylonger......the best stopper the Pilot H4 in 235/60/15 is on its last legs.When you add the pad variable to the tire variables a horribly mismatched combination [hard pads and hard tires] probably doesn't add 30 feet to stopping distances at normal temperatures [not cold weather].So rotors are not the problem.
The factory rotor has 9mm metal , 10mm air space and 9 mm metal.........some aftermarkets have 9.7mm metal and 8.6 mm air space............some cheapo aftermarkets have 8.6 mm metal and 10.8 mm air space.
You must weight and measure to know what you are getting.
Half a pound [225 grams] [3%] is significant as that may translate to a 25-35F temperature difference in aggressive stopping.
On single stop 60-80 mph decelerations there will be no change in stopping distances from the worst to the best rotors, assumming they are both [all] bedded and equally trued......unless the rotor suface metals have a difference in friction coefficients [unlikely and very small].
The pads will vary based on the pedal pressure vs friction coefficient...........best to worst probably no more than 25 feet based on 129 feet for oem rotor,pads and oem soft tires [170 tread wear index.
Typical 300-400 treadwear tires probably don't add much more than 10-15 feet in DRY stopping distances at 100F ambient and no more than 15-20 feet at 60F...............20-25 feet at 32F.
Correlations from Tire Rack 50-zero braking test - Pilot Sport Cup vs Pilot H4 in 225 vs RSA and worse tires 78>87>100 feet.
Unfortunately no 78 feet tires are available in the 15" size anylonger......the best stopper the Pilot H4 in 235/60/15 is on its last legs.When you add the pad variable to the tire variables a horribly mismatched combination [hard pads and hard tires] probably doesn't add 30 feet to stopping distances at normal temperatures [not cold weather].So rotors are not the problem.