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Gs-300 Brakes


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A couple of months ago I bought a GS-300 Sport Design with 45,000 miles on it.Seems to be in very good shape. It was a one owner Florida car. According to Lexus the front brakes were worked on at about 30,000 miles. The dealer I bought the car from had the front rotors turned because they pulsated. The rotors look good and they have 31.5 MM left. My problem is every now and then from a slow, about 25 MPH stop one of the front brakes pull. The right one is the biggest offender. This doesn't happen very often and I have never encountered it from a high speed stop. Also I have noticed the steering wheel vibrates from time to time. I suspect this is because the balance weights are all on the inside of the fancy wheels and the twofrom tires get in just the right Sync. In the old days when I owned Austin Healys we used to split the weights from side to side. Another answer might be stick on weights on the center line of the wheel rotation plane. I have rotated all the tires to see if I can find the offender. They are new tires. Anybody have a clue? The brake pull bothers me most. Ken

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I just bought the exact same car w/ 51k miles. What did you pay? I found (what i think) is a good deal of $21,500 total. Mine is silver w/ grey leather, also a Florida 1 owner. I don't know if it is considered a "pull" but my brakes behave similarly when I break at a low speed. I would most describe it as more of a slight rubbing/grinding feel towards the end of the breaking process. I haven't had it looked at yet so I am interested what you find out.

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It is perfectly acceptable to have all the weights on the inside. Lexus wheels are specifically designed to not have an exterior wheel weight lig. It just plain looks better. With an accurate balancer being operated by a skilled operator, balancing wheels in this was is perfectly ok.

A complete and thorough brake job will most likely eliminate both the shake and pull. You may have a sticking caliper or other hardware missing or damaged. There are several clips, shims, and springs which must all be present and in the proper position for the brakes to work correctly. Also, cutting the rotors is not a twenty minute job as a majority of mechanics make it out to be. The rotors should be cut only on a properly calibrated brake lathe, meticulously measured and indexed at all five possible mounting positions on the hub to ensure the smallest possible runout in the mounted assembly. This takes time. For me, it takes about three hours per axle to do properly. I made a post on this procedure here.

As well, the balance should be checked and the roundness of the tires if vibration is persistant. A road-force wheel balancer is ideal for this purpose.

Of course a four wheel alignment isn't a bad idea either. During the alignment, any worn parts in the steering or suspension can be identified. These parts could have to do with the pulling you describe, particularly if the car does not track straight without the brakes being applied.

When all is well, the car should track straight and be able to be brought to a stop in a fairly straight line without even holding onto the steering wheel. This effect can vary somewhat depending on the road surface of course.

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I just bought the exact same car w/ 51k miles. What did you pay? I found (what i think) is a good deal of $21,500 total. Mine is silver w/ grey leather, also a Florida 1 owner. I don't know if it is considered a "pull" but my brakes behave similarly when I break at a low speed. I would most describe it as more of a slight rubbing/grinding feel towards the end of the breaking process. I haven't had it looked at yet so I am interested what you find out.

I just bought the exact same car w/ 51k miles. What did you pay? I found (what i think) is a good deal of $21,500 total. Mine is silver w/ grey leather, also a Florida 1 owner. I don't know if it is considered a "pull" but my brakes behave similarly when I break at a low speed. I would most describe it as more of a slight rubbing/grinding feel towards the end of the breaking process. I haven't had it looked at yet so I am interested what you find out.

Email me direct at krearl@aol.com I have too much information to junk up the foram.

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It is perfectly acceptable to have all the weights on the inside. Lexus wheels are specifically designed to not have an exterior wheel weight lig. It just plain looks better. With an accurate balancer being operated by a skilled operator, balancing wheels in this was is perfectly ok.

A complete and thorough brake job will most likely eliminate both the shake and pull. You may have a sticking caliper or other hardware missing or damaged. There are several clips, shims, and springs which must all be present and in the proper position for the brakes to work correctly. Also, cutting the rotors is not a twenty minute job as a majority of mechanics make it out to be. The rotors should be cut only on a properly calibrated brake lathe, meticulously measured and indexed at all five possible mounting positions on the hub to ensure the smallest possible runout in the mounted assembly. This takes time. For me, it takes about three hours per axle to do properly. I made a post on this procedure here.

As well, the balance should be checked and the roundness of the tires if vibration is persistant. A road-force wheel balancer is ideal for this purpose.

Of course a four wheel alignment isn't a bad idea either. During the alignment, any worn parts in the steering or suspension can be identified. These parts could have to do with the pulling you describe, particularly if the car does not track straight without the brakes being applied.

When all is well, the car should track straight and be able to be brought to a stop in a fairly straight line without even holding onto the steering wheel. This effect can vary somewhat depending on the road surface of course.

The car tracks good and stops straight from speed. I only has 46,000 miles on it. It just had a 4 wheel alignment, new tires, and rotors turned. The wobble is intermittent as is the stopping grab. What do you think about the VSC system acting up?

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The car tracks good and stops straight from speed. I only has 46,000 miles on it. It just had a 4 wheel alignment, new tires, and rotors turned. The wobble is intermittent as is the stopping grab. What do you think about the VSC system acting up?

Highly unlikely. To test the theory, turn the VSC off and drive it.

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The car tracks good and stops straight from speed. I only has 46,000 miles on it. It just had a 4 wheel alignment, new tires, and rotors turned. The wobble is intermittent as is the stopping grab. What do you think about the VSC system acting up?

Highly unlikely. To test the theory, turn the VSC off and drive it.

I would do that if it did it more often. I have heard the wheel sensors sometimes do funny things. Have you any information on that?

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It is perfectly acceptable to have all the weights on the inside. Lexus wheels are specifically designed to not have an exterior wheel weight lig. It just plain looks better. With an accurate balancer being operated by a skilled operator, balancing wheels in this was is perfectly ok.

A complete and thorough brake job will most likely eliminate both the shake and pull. You may have a sticking caliper or other hardware missing or damaged. There are several clips, shims, and springs which must all be present and in the proper position for the brakes to work correctly. Also, cutting the rotors is not a twenty minute job as a majority of mechanics make it out to be. The rotors should be cut only on a properly calibrated brake lathe, meticulously measured and indexed at all five possible mounting positions on the hub to ensure the smallest possible runout in the mounted assembly. This takes time. For me, it takes about three hours per axle to do properly. I made a post on this procedure here.

As well, the balance should be checked and the roundness of the tires if vibration is persistant. A road-force wheel balancer is ideal for this purpose.

Of course a four wheel alignment isn't a bad idea either. During the alignment, any worn parts in the steering or suspension can be identified. These parts could have to do with the pulling you describe, particularly if the car does not track straight without the brakes being applied.

When all is well, the car should track straight and be able to be brought to a stop in a fairly straight line without even holding onto the steering wheel. This effect can vary somewhat depending on the road surface of course.

I dialed in the rotors. Left .032, right .003. So I pulled left and cleaned it up. Rusty. Now the dial is .003. It had been rotated on the hub and not cleaned up. Thanks for the tips.

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I dialed in the rotors. Left .032, right .003. So I pulled left and cleaned it up. Rusty. Now the dial is .003. It had been rotated on the hub and not cleaned up. Thanks for the tips.

No problem. Did it solve your vibration issue? What many people don't realize is that it does no good to mount a perfect rotor on an imperfect hub surface. Many times a slight vibration can be cured by only changing the position of the rotor with no need to do any surfacing to the rotor at all. It is harder to make a customer believe (and pay) when you tell them that you just rotated the rotors and fixed their problem. In fact, I have a family member that is a mechanic fo over forty years and I told him this. He replied that it was a total waste of time and laughed at me. I pity the poor souls that bring their cars to his shop.

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It solved the problem. At least below 115 MPH. I hadn't had a chance to check it until a bit ago. I had started out rotating tires, I had to do this on my 93 Aerostar. Hadn't got to the idea of rotors not being mounted correctly. They were not in the original spot according to the rust marks left by the puller bolt holes. Polished everything up and the runout went to .003 of an inch. in the same bolt hole. Had a dial indicator I bought in 1959 when we were playing with Austin Healys, and Porsche's. The lighter the machine the more you feel a bad tire. That maybe why your family member doesn't think it matters. I you drive a 4 ton SUV with knobby tires on it who can tell over the roar. So thanks for the help, I might have got to the rotor mounting after a few nights sleep. Thats how I figured out how to get the caliper bolts out. Came to me in the night. Now tell me how to wire the side lights so they are also turn lights. One wire with a diode in it should do. Ken

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  • 2 weeks later...

It solved the problem. At least below 115 MPH. I hadn't had a chance to check it until a bit ago. I had started out rotating tires, I had to do this on my 93 Aerostar. Hadn't got to the idea of rotors not being mounted correctly. They were not in the original spot according to the rust marks left by the puller bolt holes. Polished everything up and the runout went to .003 of an inch. in the same bolt hole. Had a dial indicator I bought in 1959 when we were playing with Austin Healys, and Porsche's. The lighter the machine the more you feel a bad tire. That maybe why your family member doesn't think it matters. I you drive a 4 ton SUV with knobby tires on it who can tell over the roar. So thanks for the help, I might have got to the rotor mounting after a few nights sleep. Thats how I figured out how to get the caliper bolts out. Came to me in the night. Now tell me how to wire the side lights so they are also turn lights. One wire with a diode in it should do. Ken

However: On the trip to the airport this morning it vibrated again. Will start moving wheels again to see if one has a balance problem. I'm sure the disc trueing helped, at least it didn't hurt, but once again got the light shake at 60 to 75. I hadn't driven it in a couple of days, but the tire set shouldn't have been noticable after a few miles.

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