Changing Transmission fluid, worth it? (1 Viewer)

[bobr1]

Hello,

I have a 2000 TLC with about 90k miles on it. As far as I am aware the fluid has never been replaced. Anyway, I know there are threads on this already but most of them are pretty dated and was curious if anyone has had experience with this more recently. I was driving up a road out of an intersection and felt a bad shudder and car was acting weird, fortunately it was just a coil pack and I replaced it once I got home. But at first I thought it was the dreaded 2000's transmission going out and made me think about preventive maitenance on it. So, is it worth changing out the fluid at this point? I have read horror stories of the transmission being fine then after a flush the transmissions have problems. Some people just drain it and replace it, others do the running the car to pump out the old fluid while replacing it and some don't even touch it.

I appreciate any input from you guys

Thanks,

Bob

 

[trdcorolla]

My wife's camry's transmission went out after a flush (had around 100k on it) but my 4Runner with 50k was okay after a flush. When I got my 100, I just drained and refilled it a few times in the last 2 years. Just make sure the level is right, these transmissions are sensitive to fluid level.

 

[Stepsride]

This is a question that you are going to get a bunch of folks saying do it, and another bunch of folks saying do not do it. If it were up to me I would follow the service interval.

 

[2020 Rocks]

Drain and fill is the safest way to go about it. Will take approx 3 times to cycle all the old fluid out as a significant amount of fluid does not fully drain each time. I would stay away from flushing.

 

[flintknapper]

Hello,

I have a 2000 TLC with about 90k miles on it. As far as I am aware the fluid has never been replaced. Anyway, I know there are threads on this already but most of them are pretty dated and was curious if anyone has had experience with this more recently. I was driving up a road out of an intersection and felt a bad shudder and car was acting weird, fortunately it was just a coil pack and I replaced it once I got home. But at first I thought it was the dreaded 2000's transmission going out and made me think about preventive maitenance on it. So, is it worth changing out the fluid at this point? I have read horror stories of the transmission being fine then after a flush the transmissions have problems. Some people just drain it and replace it, others do the running the car to pump out the old fluid while replacing it and some don't even touch it.

I appreciate any input from you guys

Thanks,

Bob

Hi Bob,

Conventional wisdom concerning a transmission the service history of which is unknown....would be to do a series of 'drain and fills' (over time). This will offer the safest way to achieve a fluid re-freshening. After several drain and fills (over a period of time and miles) you will eventually have nearly new fluid.


The next best procedure would be to do a 'fluid exchange' using the transmission's own pump (or a low pressure pump at a service facility). You will get ALL of the old fluid out of the torque converter and internals with that method.

A 'full on' high pressure 'flush' is rarely done anymore for just the reason you cite (transmission trouble). We want to avoid possibly stirring up/dislodging any debris (old friction material, metal particles, etc) and having them lodge in the Valve Body.

I would not be afraid in the least to do drain and fills. Your model year A343F transmission did have a production 'window' that suggests certain internal parts were substandard and prone to early failure...but by no means was every vehicle affected.

 

[2020 Rocks]

Hi Bob,

Conventional wisdom concerning a transmission the service history of which in unknown....would be to a series of 'drain and fills' (over time). This will offer the safest way to achieve a fluid re-freshening. After several drain and fills (over a period of time and miles) you will eventually have nearly new fluid.


The next best procedure would be to do a 'fluid exchange' using the transmissions own pump (or a low pressure pump at a service facility). You will get ALL of the old fluid out of the torque converter and internals with that method.

A 'full on' high pressure 'flush' is rarely done anymore for just the reason you cite (transmission trouble). We want to avoid possibly stirring up/dislodging any debris (old friction material, metal particles, etc) and having them lodge in the Valve Body.

I would not be afraid in the least to do drain and fills. Your model year A343F transmission did have a production 'window' that suggests certain internal parts were substandard and prone to early failure...but by no means was every vehicle affected.

This is spot on, treat it as an additional step when you do your next three oil changes. Drain and fill the tranny at the same time you change your oil. In about a year's time you will have effectively and gently replaced nearly all of the old fluid with new.

 

[BEG]

This is spot on, treat it as an additional step when you do your next three oil changes. Drain and fill the tranny at the same time you change your oil. In about a year's time you will have effectively and gently replaced nearly all of the old fluid with new.

This is exactly the method that I use. I work it into a couple of oil changes. Keeps the new fluid from shocking the trans (if that's even a thing) and less fiddly than dealing with brittle connections at the radiator. Of course, there's the danger of buggering up the drain plug threads. Pick your poison.

 

[bobr1]

Thanks guys, really appreciate the input. Looks like I will do the drain and fill when I do oil changes.

I was under the impression that if the clutch material wore down on high mileage transmissions it created a suspension of the clutch material in the fluid and that it stilled allowed the clutches to work. But after removing the old fluid all the clutch material that was suspended was removed and caused slipping of the clutches in the transmission and or the particulate clogging the valve body. But it seems like several people have done it with out any issues.

 

[apdxyk]

What funnel do people use? I find the dipstick tube diameter to be narrower than 'regular and customary'

 

[flintknapper]

Thanks guys, really appreciate the input. Looks like I will do the drain and fill when I do oil changes.

I was under the impression that if the clutch material wore down on high mileage transmissions it created a suspension of the clutch material in the fluid and that it stilled allowed the clutches to work. But after removing the old fluid all the clutch material that was suspended was removed and caused slipping of the clutches in the transmission and or the particulate clogging the valve body. But it seems like several people have done it with out any issues.

If your transmission has to rely on a 'slurry' of contaminated fluid to provide enough friction...then it is on its last legs anyway.

The A343F is noted for long life (I have 310K on one and 220K) on the other and both are going strong.

If you have any problems with it...it will be shift solenoids or plastic thrust washers.

Edit: Mileage now 325K and 240K respectively. I do a 'drain and fill' at least annually. Perhaps its not necessary, but it gives me peace of mind and my transmissions run trouble free and cool.

 

[bobr1]

If your transmission has to rely on a 'slurry' of contaminated fluid to provide enough friction...then it is on its last legs anyway.

The A343F is noted for long life (I have 310K on one and 220K) on the other and both are going strong.

If you any problems with it...it will be shift solenoids or plastic thrust washers.

Thanks for all the helpful info flintknapper.