Amsoil ATF:pan drop every 30K or full flush 100K?
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Originally Posted By: Kuato
Originally Posted By: Trav
There is no such thing as a flush! ...
Transmission flush machine?
No such animal, its a fluid exchange machine nothing more. Some comanies call them flush machines but its only advertizing speak.
Exchanging all the fluid is no different to the transmission than a drain and fill but it sure is easier on the wallet.
The main reason for the apparent higher failure rate is a lot of the time people would do a "flush" as a last ditch effort to fix a sick unit. It would have died anyway.
Most of the time drain and fills were done as maintenance. In reality a full exchange is far more beneficial than a drain and fill when performad as maintenance.
Still the myth continues.
Originally Posted By: Trav
There is no such thing as a flush! ...
Transmission flush machine?
No such animal, its a fluid exchange machine nothing more. Some comanies call them flush machines but its only advertizing speak.
Exchanging all the fluid is no different to the transmission than a drain and fill but it sure is easier on the wallet.
The main reason for the apparent higher failure rate is a lot of the time people would do a "flush" as a last ditch effort to fix a sick unit. It would have died anyway.
Most of the time drain and fills were done as maintenance. In reality a full exchange is far more beneficial than a drain and fill when performad as maintenance.
Still the myth continues.
Originally Posted By: Trav
The main reason for the apparent higher failure rate is a lot of the time people would do a "flush" as a last ditch effort to fix a sick unit. It would have died anyway.
I agree with this somewhat, however a buddy of mine that worked at a trans shop for several years says flush/exchange (without filter) is what kills trannies most often because the fresh detergents in flush/exchange dislodges all the gunk and plugs the filter causing low hydraulic pressure and slipping clutches in his opinion.
I follow his advise and disconnect the cooler, run the engine to pump out ~2 qts of fluid (so the pan doesn't drip), drop the pan, clean the pan and magnet, replace the filter, reassemble, refill the pan through the dipstick tube, then use the trans pump to exchange the remaining fluid using the two-bucket method until it runs clean through the (clear) hose on the pressure side of the cooler lines. That's for a trans that has unknown history or known neglect. Regular filter/top-off (partial change) is suitable for a trans with a good known service history.
New filter and full fluid exchange is best, new filter and 3-6 quarts is second best, anything that doesn't involve a new filter is dangerous in his opinion.
The main reason for the apparent higher failure rate is a lot of the time people would do a "flush" as a last ditch effort to fix a sick unit. It would have died anyway.
I agree with this somewhat, however a buddy of mine that worked at a trans shop for several years says flush/exchange (without filter) is what kills trannies most often because the fresh detergents in flush/exchange dislodges all the gunk and plugs the filter causing low hydraulic pressure and slipping clutches in his opinion.
I follow his advise and disconnect the cooler, run the engine to pump out ~2 qts of fluid (so the pan doesn't drip), drop the pan, clean the pan and magnet, replace the filter, reassemble, refill the pan through the dipstick tube, then use the trans pump to exchange the remaining fluid using the two-bucket method until it runs clean through the (clear) hose on the pressure side of the cooler lines. That's for a trans that has unknown history or known neglect. Regular filter/top-off (partial change) is suitable for a trans with a good known service history.
New filter and full fluid exchange is best, new filter and 3-6 quarts is second best, anything that doesn't involve a new filter is dangerous in his opinion.
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Originally Posted By: linksep
Originally Posted By: Trav
The main reason for the apparent higher failure rate is a lot of the time people would do a "flush" as a last ditch effort to fix a sick unit. It would have died anyway.
I agree with this somewhat, however a buddy of mine that worked at a trans shop for several years says flush/exchange (without filter) is what kills trannies most often because the fresh detergents in flush/exchange dislodges all the gunk and plugs the filter causing low hydraulic pressure and slipping clutches in his opinion.
I follow his advise and disconnect the cooler, run the engine to pump out ~2 qts of fluid (so the pan doesn't drip), drop the pan, clean the pan and magnet, replace the filter, reassemble, refill the pan through the dipstick tube, then use the trans pump to exchange the remaining fluid using the two-bucket method until it runs clean through the (clear) hose on the pressure side of the cooler lines. That's for a trans that has unknown history or known neglect. Regular filter/top-off (partial change) is suitable for a trans with a good known service history.
New filter and full fluid exchange is best, new filter and 3-6 quarts is second best, anything that doesn't involve a new filter is dangerous in his opinion.
I agree with him 100% and thats exactly what i posted earlier in this thread. On some transmissions i pump it out first then drop the pan, others with a drain plug just drain it first, get the filter changed then pop the line. Same difference, the filter still gets changed.
Originally Posted By: trav
Drop the pan, replace the filter, add the same Amount of fluid that came out then drop the return line before starting the engine.
Connect a piece of vinyl tubing to the return line and put it a gallon container. Start the engine and run it till the jug is full, add a gallon and repeat until the fluid is the same color as the fluid going in.
Fill the fluid to the lower mark, drive it till warm then check the level.
Originally Posted By: Trav
The main reason for the apparent higher failure rate is a lot of the time people would do a "flush" as a last ditch effort to fix a sick unit. It would have died anyway.
I agree with this somewhat, however a buddy of mine that worked at a trans shop for several years says flush/exchange (without filter) is what kills trannies most often because the fresh detergents in flush/exchange dislodges all the gunk and plugs the filter causing low hydraulic pressure and slipping clutches in his opinion.
I follow his advise and disconnect the cooler, run the engine to pump out ~2 qts of fluid (so the pan doesn't drip), drop the pan, clean the pan and magnet, replace the filter, reassemble, refill the pan through the dipstick tube, then use the trans pump to exchange the remaining fluid using the two-bucket method until it runs clean through the (clear) hose on the pressure side of the cooler lines. That's for a trans that has unknown history or known neglect. Regular filter/top-off (partial change) is suitable for a trans with a good known service history.
New filter and full fluid exchange is best, new filter and 3-6 quarts is second best, anything that doesn't involve a new filter is dangerous in his opinion.
I agree with him 100% and thats exactly what i posted earlier in this thread. On some transmissions i pump it out first then drop the pan, others with a drain plug just drain it first, get the filter changed then pop the line. Same difference, the filter still gets changed.
Originally Posted By: trav
Drop the pan, replace the filter, add the same Amount of fluid that came out then drop the return line before starting the engine.
Connect a piece of vinyl tubing to the return line and put it a gallon container. Start the engine and run it till the jug is full, add a gallon and repeat until the fluid is the same color as the fluid going in.
Fill the fluid to the lower mark, drive it till warm then check the level.
Some current vehicles have non-serviceable filters as well as no dipstick. What do you think the best regimen for those are? Frequent (30K miles) drain and fills? Less frequent fluid exchange? Something else?
Even on well maintained trannies, I often see a light, discolored layer on a removed tranny pan. It seems that with a non serviceable filter, one wants to keep the grime layer to a minimum.
Sorry to wander off topic, but this is a good drain vs. exchange discussion.
Even on well maintained trannies, I often see a light, discolored layer on a removed tranny pan. It seems that with a non serviceable filter, one wants to keep the grime layer to a minimum.
Sorry to wander off topic, but this is a good drain vs. exchange discussion.
Some vehicles don't have a pan or replaceable filter (they do but the transmission needs to be dissembled to do it). Just a fluid exchange every 50K.
These units usually have large filters or 2 of them up in the case and a rock catcher on the tube.
They last a long time because they are not subjected to the debris on the bottom of the pan or case just whats in the fluid.
I am not a fan of this sort of arrangement i prefer a real filter that i can change.
A good inline filter can be a real benefit to these units if its installed early in life.
These units usually have large filters or 2 of them up in the case and a rock catcher on the tube.
They last a long time because they are not subjected to the debris on the bottom of the pan or case just whats in the fluid.
I am not a fan of this sort of arrangement i prefer a real filter that i can change.
A good inline filter can be a real benefit to these units if its installed early in life.
I install a trans pan drain plug in every vehicle I've ever owned.
When due, I first pull the pan and change the filter and weld on an "AN" fitting as a drain plug. Then each oil change also gets 4 new transmission quarts. No need to flush, the trans oil is always clean.
300,000 troublefree miles is the result.
When due, I first pull the pan and change the filter and weld on an "AN" fitting as a drain plug. Then each oil change also gets 4 new transmission quarts. No need to flush, the trans oil is always clean.
300,000 troublefree miles is the result.
Years ago, I tried the "fluid exchange" thing on my 98 F150 and got out about 4 quarts of dirty fluid, then it flowed clean. I guess it did not flush the torque converter. It simply picked up the clean fluid from the pan and pumped it through the line to the cooler.
It sounds like operator error to me. I just did a 01 4R100 and got 16 qts out before it started to run clear so it definitely got the converter.
The engine has to be running or the tranny pump wont work.
The engine has to be running or the tranny pump wont work.
Originally Posted By: Cujet
Years ago, I tried the "fluid exchange" thing on my 98 F150 and got out about 4 quarts of dirty fluid, then it flowed clean. I guess it did not flush the torque converter. It simply picked up the clean fluid from the pan and pumped it through the line to the cooler.
Its suppose to pick up the clean fluid and pump it through the transmission and torque converter and out to the cooling hose. What was the total capacity? There is no real way for it to bypass the torque converter.
Some cars need to ne in N rather than P for it to work. Some cars also have a thermostat in the cooling line that returns the fluid before the cooler.
Years ago, I tried the "fluid exchange" thing on my 98 F150 and got out about 4 quarts of dirty fluid, then it flowed clean. I guess it did not flush the torque converter. It simply picked up the clean fluid from the pan and pumped it through the line to the cooler.
Its suppose to pick up the clean fluid and pump it through the transmission and torque converter and out to the cooling hose. What was the total capacity? There is no real way for it to bypass the torque converter.
Some cars need to ne in N rather than P for it to work. Some cars also have a thermostat in the cooling line that returns the fluid before the cooler.
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Originally Posted By: Trav
It sounds like operator error to me. I just did a 01 4R100 and got 16 qts out before it started to run clear so it definitely got the converter.
The engine has to be running or the tranny pump wont work.
I did it with the engine running, in park. 4R70W transmission. This was back 15 years ago. I'm not sure what, or even if I did it improperly.
I switched to the "drain 4 quarts" from the trans at each oil change methodology.
It sounds like operator error to me. I just did a 01 4R100 and got 16 qts out before it started to run clear so it definitely got the converter.
The engine has to be running or the tranny pump wont work.
I did it with the engine running, in park. 4R70W transmission. This was back 15 years ago. I'm not sure what, or even if I did it improperly.
I switched to the "drain 4 quarts" from the trans at each oil change methodology.
Sorry i am not familiar enough with the machines to say what was wrong, i do a line off and it gets all of it every time.
Maybe you did nothing wrong, the machine itself may have been duff?
Maybe you did nothing wrong, the machine itself may have been duff?
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