Michelin Primacy MXM4 on a IS250 AWD?
05-12-12, 11:07 PM
#46
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why more in the front than rear?
05-13-12, 07:20 PM
#50
That's actually why his suggestion doesn't make much sense for an ISx50.
makes sense for a FWD car that has most of its weight in front due to the transaxle and applies driveline power to those wheels too.
Not so much a RWD car where it's 52/48 weight balance, and 100% of the driveline force is applied to the rear wheels.
38 front, 40 rear, is what my alignment/tire guy suggested, and what I've run the last 15k or so.
makes sense for a FWD car that has most of its weight in front due to the transaxle and applies driveline power to those wheels too.
Not so much a RWD car where it's 52/48 weight balance, and 100% of the driveline force is applied to the rear wheels.
38 front, 40 rear, is what my alignment/tire guy suggested, and what I've run the last 15k or so.
05-13-12, 08:15 PM
#51
That's actually why his suggestion doesn't make much sense for an ISx50.
makes sense for a FWD car that has most of its weight in front due to the transaxle and applies driveline power to those wheels too.
Not so much a RWD car where it's 52/48 weight balance, and 100% of the driveline force is applied to the rear wheels.
38 front, 40 rear, is what my alignment/tire guy suggested, and what I've run the last 15k or so.
makes sense for a FWD car that has most of its weight in front due to the transaxle and applies driveline power to those wheels too.
Not so much a RWD car where it's 52/48 weight balance, and 100% of the driveline force is applied to the rear wheels.
38 front, 40 rear, is what my alignment/tire guy suggested, and what I've run the last 15k or so.
05-13-12, 09:02 PM
#52
But the IS and GS, even the AWD ones, are RWD biased I believe, hence the factory recommendation for higher rear pressure (even if it's too low overall)... something FWD-biases like an AWD RX350 might be a different case (I dunno, don't have one to check the recommended pressures)
Last edited by Kurtz; 05-14-12 at 06:51 AM.
05-14-12, 05:41 AM
#53
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I replaced my OEm re92s with general gmax as-03 tires. Don't laugh! They are excellent tires for the price, offer superlative grip and handling, at the expense of mild increase in road noise.
As for pressure, last I checked the AWD should be 35 front, 38 back.
As for pressure, last I checked the AWD should be 35 front, 38 back.
05-15-12, 10:19 AM
#56
Found out from my tech. Explained in a cut down version to me.
It was set this way because of more city driving compared to highway driving. The higher pressure at the front is to lower the rolling resistance so the tires so they do not have to work because of turning. This will maximize the longevity of the tire.
If I call correctly, if it were more for freeway driving, then it would have it flipped the other way with the rears being higher.
It was set this way because of more city driving compared to highway driving. The higher pressure at the front is to lower the rolling resistance so the tires so they do not have to work because of turning. This will maximize the longevity of the tire.
If I call correctly, if it were more for freeway driving, then it would have it flipped the other way with the rears being higher.
05-16-12, 07:31 PM
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Not needed. The IS 250 awd is a very well balanced car. It chews through front and rear tires at a very uniform rate. Even the front and rear brakes wear evenly.
05-16-12, 08:34 PM
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05-16-12, 09:04 PM
#60
No, it's not dependent on that. Even if it was... it's not comparable to what the front tires are experiencing compared to the rear in terms of friction. Can easily replicate testing your own hand.
What is happening when you steer the car and turning? You're changing the camber, which is variable camber. The rear does not steer so the cambers is fixed, it does not change.
What is happening when you steer the car and turning? You're changing the camber, which is variable camber. The rear does not steer so the cambers is fixed, it does not change.
Last edited by Sango; 05-16-12 at 09:18 PM.