My son's 2010 Toyota Corolla has 100,000 miles on it. Transmission fluid never changed. Friends 2009 Venza; same thing.
I have seen several options discussed:
1. Only do one drain and fill.
2. Do several drain and fills.
3. Drain, fill. Then unhook transmission line and let transmission pump fluid out, replacing one quart at every quart pumped out. Do this until fluid runs clean (this is what I typically do).
4. Do transmission flush with flush machine. No one seems to recommend this out of concern that deposits will be broken loose and cause damage.
5. Do nothing. Because the transmission fluid was not changed earlier then deposits have built up. If you do any of the above 1-4 you run the risk of damaging the transmission.
Toyota says don't do anything as fluid is lifetime: this is pure bunk IMO. Car Care Nut (CCN) guy says only do 1 or 2. But if high mileage, do 5 (nothing). I really respect CCN but he never showed any evidence of 1 or 2 causing a problem with high mileage transmission.
To those that advocate 5, I have never seen anyone produce evidence that 1-3 ever caused a documented problem. But maybe I have missed that in my internet searches.
So please, provide your recommendations. And provide any proof you have, for or against any of the options.
Thanks.
I have seen several options discussed:
1. Only do one drain and fill.
2. Do several drain and fills.
3. Drain, fill. Then unhook transmission line and let transmission pump fluid out, replacing one quart at every quart pumped out. Do this until fluid runs clean (this is what I typically do).
4. Do transmission flush with flush machine. No one seems to recommend this out of concern that deposits will be broken loose and cause damage.
5. Do nothing. Because the transmission fluid was not changed earlier then deposits have built up. If you do any of the above 1-4 you run the risk of damaging the transmission.
Toyota says don't do anything as fluid is lifetime: this is pure bunk IMO. Car Care Nut (CCN) guy says only do 1 or 2. But if high mileage, do 5 (nothing). I really respect CCN but he never showed any evidence of 1 or 2 causing a problem with high mileage transmission.
To those that advocate 5, I have never seen anyone produce evidence that 1-3 ever caused a documented problem. But maybe I have missed that in my internet searches.
So please, provide your recommendations. And provide any proof you have, for or against any of the options.
Thanks.