Synthetic transmission fluid questions

Old 11-09-07, 10:35 AM
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Synthetic transmission fluid questions

I have 2 questions regarding a Toyota Corolla with 146,000 miles.

1. I've heard that a tranny flush on a high mileage vehicle can cause problems with dislodged material. Is it risky to just drop the pan (or drain if there's a plug) and top off the fluid? Does that adequately refresh the fluid? Right now I don't have synthetic, but would like to go there - is it ok to mix synthetic with the non-synthetic that's already there?

2. Regarding the power steering fluid - same question about mixing non-synthetic with synthetic.

The specs on my Corolla say Dexron II for both the tranny and power steering.

Old 11-09-07, 12:43 PM
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1. Yes, it's possible a flush can open things up; same is true for simply servicing it. This normally applies to vehicles which have had their preventive maintenance ignored and are being held together by the crud. I wouldn't waste my money on a transmission fluid flush on ANY car. If you have been taking reasonable care of your vehicle, regular fluid changes will make it go a long ways. I think your Corolla probably has a drain plug and a cleanable screen under the pan. Drain and refill at regular intervals (I prefer 25,000 miles) and you'll be fine. Save your money and use garden-variety fluid; skip the synthetic.

2. Ditto on synthetic for the PS. Although it will mix, save your $. If you REALLY want to use synthetic somewhere, spend your dollars for synthetic motor oil.
Old 11-09-07, 02:36 PM
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And keep to the dead dino juice on this high miler
Most of the benefits (of synth) are wasted in this particular instance
Use the synth on your next new car after the break in period if you want to get your money's worth

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