I am considering performing an ATF flush of my wife's 2014 Rav4 as well as dropping the pan to replace the filter and clean the pan and magnets. The ATF has apprx 90k miles on it. I going to use the ATF return line method. I have used this flush method successfully on my 05 Tacoma. I see many prefer to drain and refill even though this method only replaces about 1/2 of the total transmission ATF capacity. Why would replacing 1/2 the ATF be preferable over a low pressure flush? Thanks in advance for your feedback.
Drain/refill vs diy flush?
- Thread starter Back40
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Yes, if you have the experience in flushing a tranny with good success then certainly do so. I like dropping the pan and changing out the screen/filter(whatever) and moving new fluid through the cooler lines as well. However, I do drain & refills often in between the flush by just unbolting the drain pan bolt and let the fluid drain and replacing what I've removed.
Good to see you taking interest in this PM.
Good to see you taking interest in this PM.
Most like to hear a term like "fluid exchange" vs. a flush. Having said that a pan drop filter replacement with a cooler line fluid exchange imo is the best possible way to service a transmission. A pan drop filter change leaves a lot more old fluid in the system to mix with the fresh new fluid.
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
Originally Posted by BMWTurboDzl
Originally Posted by Back40
I am considering performing an ATF flush of my wife's 2014 Rav4 as well as dropping the pan to replace the filter and clean the pan and magnets. The ATF has apprx 90k miles on it. I going to use the ATF return line method. I have used this flush method successfully on my 05 Tacoma. I see many prefer to drain and refill even though this method only replaces about 1/2 of the total transmission ATF capacity. Why would replacing 1/2 the ATF be preferable over a low pressure flush? Thanks in advance for your feedback.
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
As per demarpaint, I will be performing a "fluid exchange" and not a pressurized flush.
Originally Posted by Back40
I am considering performing an ATF flush of my wife's 2014 Rav4 as well as dropping the pan to replace the filter and clean the pan and magnets. The ATF has apprx 90k miles on it. I going to use the ATF return line method. I have used this flush method successfully on my 05 Tacoma. I see many prefer to drain and refill even though this method only replaces about 1/2 of the total transmission ATF capacity. Why would replacing 1/2 the ATF be preferable over a low pressure flush? Thanks in advance for your feedback.
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
As per demarpaint, I will be performing a "fluid exchange" and not a pressurized flush.
Originally Posted by Back40
As per demarpaint, I will be performing a "fluid exchange" and not a pressurized flush.
As per demarpaint, I will be performing a "fluid exchange" and not a pressurized flush.
Originally Posted by BMWTurboDzl
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
Where did you come up with this load of crap?
Do you know how a flush or total fluid exchange is performed? It uses the pump in the transmission to push the new ATF through the transmission just like it does when you are driving. The flush machine only refills the pan with new ATF at the same rate that the transmission pump pushes old fluid out. There is no high pressure involved. However you introduce new ATF will clean the transmission of sludge and contaminants which is what you want. If a total fluid exchange causes any transmission issues the transmission was on its way out.
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
Where did you come up with this load of crap?
Do you know how a flush or total fluid exchange is performed? It uses the pump in the transmission to push the new ATF through the transmission just like it does when you are driving. The flush machine only refills the pan with new ATF at the same rate that the transmission pump pushes old fluid out. There is no high pressure involved. However you introduce new ATF will clean the transmission of sludge and contaminants which is what you want. If a total fluid exchange causes any transmission issues the transmission was on its way out.
Exchanging all the ATF at one time is the most efficient way to get a high percentage of the old ATF exchanged with new while wasting little new ATF. Dropping the pan in the process to replace the filter is also a good idea. Installing a Magnefine filter can help also. Doing multiple drain & fill wastes a lot of new ATF trying to get to a high percentage of ATF replaced. When you are using expensive synthetic ATF, why waste the ATF?
I was under the impression that most of what passes for a complete shop "flush" these days, is basically a trans return line exchange of all fluid. The difference, done with a machine rather than passive diy. I think the biggest issue folks like Honda have with ATF "flush", is when chemicals are added to the process. Then it becomes a
My .02
My BIL doesn't change any of their vehicles tranny fluids and he never seems to have any issues even in a CVT tranny. However, in his Toyota vehicle, he does indeed keep'em longer(250K-300K miles) than any other make. And again, doesn't do a thing to the trannies...EVER! Maybe during the QuikLube OCI, they may check/add ATF, IDK. And he may in fact over change the oil & filter by BITOG standards simply due to being a bit ol'school in his thinking.
Originally Posted by Donald
Originally Posted by BMWTurboDzl
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
Where did you come up with this load of crap?
Do you know how a flush or total fluid exchange is performed? It uses the pump in the transmission to push the new ATF through the transmission just like it does when you are driving. The flush machine only refills the pan with new ATF at the same rate that the transmission pump pushes old fluid out. There is no high pressure involved. However you introduce new ATF will clean the transmission of sludge and contaminants which is what you want. If a total fluid exchange causes any transmission issues the transmission was on its way out.
Over the years these are general reasons I was give with regards to why you would want to avoid a flush. As for your final comment the argument against is that the crud dislodges from some place where it's NOT causing an issue and it moves into a place where is does cause an issue. There is absolutely NO REASON to assume that it would exit the unit...zero..nada. It's akin to giving your transmission a stroke.
Over the years when speaking to transmission guys their opinion often went like this:
"If the unit has a lot of miles and is failing, go ahead an do a flush, you can't break it more than it's already broken."
"I've seen over-maintained transmissions fail at about the same rate as transmissions which weren't maintained. It really depends on the design of the transmission rather than how often you decide to change the fluid.".
Now my own opinion is to either over-maintain or don't and your mileage may very, just don't be fooled into thinking the unit will last longer simply because your changed the ATF every 30k miles.
Originally Posted by BMWTurboDzl
IIRC the general argument(s) against a flush are:
#1 Dislodges crude in a neglected transmission which causes a failure.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
#3 Flush is performed using excessive pressure.
#4 Flush has never been proven to extend the life of a transmission and instead just increases the risk of introducing contaminants into the unit.
Again these are general arguments and some may/may not apply to your particular transmission.
Where did you come up with this load of crap?
Do you know how a flush or total fluid exchange is performed? It uses the pump in the transmission to push the new ATF through the transmission just like it does when you are driving. The flush machine only refills the pan with new ATF at the same rate that the transmission pump pushes old fluid out. There is no high pressure involved. However you introduce new ATF will clean the transmission of sludge and contaminants which is what you want. If a total fluid exchange causes any transmission issues the transmission was on its way out.
Over the years these are general reasons I was give with regards to why you would want to avoid a flush. As for your final comment the argument against is that the crud dislodges from some place where it's NOT causing an issue and it moves into a place where is does cause an issue. There is absolutely NO REASON to assume that it would exit the unit...zero..nada. It's akin to giving your transmission a stroke.
Over the years when speaking to transmission guys their opinion often went like this:
"If the unit has a lot of miles and is failing, go ahead an do a flush, you can't break it more than it's already broken."
"I've seen over-maintained transmissions fail at about the same rate as transmissions which weren't maintained. It really depends on the design of the transmission rather than how often you decide to change the fluid.".
Now my own opinion is to either over-maintain or don't and your mileage may very, just don't be fooled into thinking the unit will last longer simply because your changed the ATF every 30k miles.
Sure,you can almost all the fluid exchanged in the converter. The converter is in the flow circuit, and a line off exchange is the most efficient and best way to do it.
https://www.cartechbooks.com/techtips/torqueconverter/
https://www.cartechbooks.com/techtips/torqueconverter/
Originally Posted by badtlc
even the low pressure flush will only get you about 50% replacement due to the torque converter designs. 100% flush isn't possible no matter how you slice it.
If you do the fluid exchange via cooling hose you will have done the best you can do. Certainly more ATF will be replaced than a simple drain & fill.
even the low pressure flush will only get you about 50% replacement due to the torque converter designs. 100% flush isn't possible no matter how you slice it.
If you do the fluid exchange via cooling hose you will have done the best you can do. Certainly more ATF will be replaced than a simple drain & fill.
https://wagonmaster.net/equipment/#transmission
BG PF5 Power Flush and Fluid Exchange System
Part No. PF5HO (High output model for low-flow transmissions)
I think BG Products are partly to blame for some of this confusion. Just how powerful is their "power flush" "high output" system?
BG PF5 Power Flush and Fluid Exchange System
Part No. PF5HO (High output model for low-flow transmissions)
I think BG Products are partly to blame for some of this confusion. Just how powerful is their "power flush" "high output" system?
Originally Posted by BMWTurboDzl
Now my own opinion is to either over-maintain or don't and your mileage may very, just don't be fooled into thinking the unit will last longer simply because your changed the ATF every 30k miles.
This is highly dependent on the transmission....and also style of driving. Go the recommended 30K miles on your AX4N Ford transmission and you will probably shorten the life considerably. Go to 15K-20K intervals and you will almost certainly lengthen the life considerably. Some transmissions in smaller cars are so well built they really aren't than sensitive to fluid changes.
I've done a couple transmission cooler line flushes with a pan drop and I can attest that ALL the old fluid comes out after pumping/dumping about 15-20% more fluid than the system capacity. When it finally comes out perfectly clear for a while....that's fully cleaned....or at least 95%+.
Now my own opinion is to either over-maintain or don't and your mileage may very, just don't be fooled into thinking the unit will last longer simply because your changed the ATF every 30k miles.
This is highly dependent on the transmission....and also style of driving. Go the recommended 30K miles on your AX4N Ford transmission and you will probably shorten the life considerably. Go to 15K-20K intervals and you will almost certainly lengthen the life considerably. Some transmissions in smaller cars are so well built they really aren't than sensitive to fluid changes.
I've done a couple transmission cooler line flushes with a pan drop and I can attest that ALL the old fluid comes out after pumping/dumping about 15-20% more fluid than the system capacity. When it finally comes out perfectly clear for a while....that's fully cleaned....or at least 95%+.
If you plan to keep the vehicle long-term, it's a good idea to drop the pan at least once and see what is going on on there... replace the filter and gasket. I would guess the reason some people prefer the drain & fill method over the return line "flush" method is because it's just easier, and perhaps less messy. I dropped the pan once on my 2006 Tacoma at 120k miles, cleaned the magnets, replaced the filter & gasket -- there was hardly any buildup at all on the magnets and everything looked great. Based on this (and how I use this truck), there is no reason to drop it again. Doing drain & fills every 30-40k from here forward.
Kestas
Staff member
Originally Posted by BMWTurboDzl
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
This statement makes absolutely no sense. If clutch material is so beneficial to shifting (and lack of it so problematic), they would formulate clutch material into the initial fill. I don't know where people get these statements.
I maintain my transmissions with a complete fluid exchange every 30K. I routinely get at least 200K out of my transmissions. My friends who believe in fill-for-life typically have the transmission start hiccuping at 100-150K.
Let's just say that I've been "fooled" into believing transmission maintenance has a positive effect on the longevity of one of the most expensive parts on you car.
#2 Although the clutches are worn there is clutch material floating around in the existing ATF which assists with shifting. A flush removes this material so shift problems occur.
This statement makes absolutely no sense. If clutch material is so beneficial to shifting (and lack of it so problematic), they would formulate clutch material into the initial fill. I don't know where people get these statements.
I maintain my transmissions with a complete fluid exchange every 30K. I routinely get at least 200K out of my transmissions. My friends who believe in fill-for-life typically have the transmission start hiccuping at 100-150K.
Let's just say that I've been "fooled" into believing transmission maintenance has a positive effect on the longevity of one of the most expensive parts on you car.
Originally Posted by HangFire
https://wagonmaster.net/equipment/#transmission
BG PF5 Power Flush and Fluid Exchange System
Part No. PF5HO (High output model for low-flow transmissions)
I think BG Products are partly to blame for some of this confusion. Just how powerful is their "power flush" "high output" system?
The owners manual of the PF5 indicates that the vehicle transmission pump is doing the work of exchanging the fluid. The YouTube videos on the PF5HO indicate that there is a 12 volt pump added to the PF5 model to help make exchange faster (under 10 minutes) on certain transmission models. The videos show pressures under 15 pounds, but I may not be interpreting things correctly.
I did not get the impression that there is any kind of high pressure power flushing going on. Maybe someone else will chime in. I think the powerflush in BG lingo refers to the cleaning additive they put in the system for 15 minutes prior to doing the actual exchange.
https://wagonmaster.net/equipment/#transmission
BG PF5 Power Flush and Fluid Exchange System
Part No. PF5HO (High output model for low-flow transmissions)
I think BG Products are partly to blame for some of this confusion. Just how powerful is their "power flush" "high output" system?
The owners manual of the PF5 indicates that the vehicle transmission pump is doing the work of exchanging the fluid. The YouTube videos on the PF5HO indicate that there is a 12 volt pump added to the PF5 model to help make exchange faster (under 10 minutes) on certain transmission models. The videos show pressures under 15 pounds, but I may not be interpreting things correctly.
I did not get the impression that there is any kind of high pressure power flushing going on. Maybe someone else will chime in. I think the powerflush in BG lingo refers to the cleaning additive they put in the system for 15 minutes prior to doing the actual exchange.
I think the idea is that when you get a used car and the trans fluid looks bad, you should exchange the fluid. Regular D&Fs should do the trick after that. That's why you see members with newer cars doing D&Fs, because their fluid has not gotten contaminated to the point of needing to be exchanged.
Do you guys put additives in your trans when you exchange the fluid? If so how? Drain the corresponding amount of fresh fluid after the exchange?
Do you guys put additives in your trans when you exchange the fluid? If so how? Drain the corresponding amount of fresh fluid after the exchange?
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