[hotrice]

Originally Posted by navylife59

Why the need to downshift; racing, hard stops, or just force of habit? For everyday driving, you really don't need to downshift. Just leave it in gear till the RPM's get low (dont' bog) around 1.8K then either go to neutral or downshift. This puts very little strain on your drivetrain. If you are racing, then you should not be concerned with the longevity of your clutch. You need max performance for the win. Hard stops, then I say just do it and don't worry about anything else. If you need to stop, then hard downshifting (correctly), along with progressively harder breaking is the name of the game. The key here is to not downshift at too high an RPM or you risk breaking the tires loose, killing your chances of stopping quickly.

Be that as it may, claytongozoom is CORRECT about the undue strain that is put on a transmission when downshifting hard at high RPM's. Sudden pressure and heat buildup of the clutch impounding the speeding flywheel could creat stress fractures on the flywheel mating surface. At the least it grabs an extra layer of wear on the clutch pad. If you do this habitually for every stop, then yes, you could be putting undue stress and wear on your drive train. On boosted apps, the sudden increase in cylinder head pressures could lead to failed gaskets/seals or worse; cylinder wall fractures. Of course, that would be the case if we were sporting a domestic iron block built prior to the turn of the century. You would have to be a heavy downshifter and popping the clutch at high RPM's to cause that kind of damage. Don't misunderstand me. You can destroy, even a 2AZ-FE by abusing it daily. I am at 43K with the stock brake, tires, and clutch that Scion sent with the car. I do downshift and/or brake hard at times. I am amazed at how tough this motor is stock.

navy i know i will be looked at funny for asking you this but are you saying that it would be ok to down shift hard to help slow down???