I agree.
Transmission Fluid change philosophies
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Originally Posted By: KrisZ
The reason these stories always come up is because people that neglect their cars are very quick to point a finger at something else rather than themselves.
In their mind its the new fluid that killed the tranny, not lack of maintenence.
Also these kind of people usually go for a flush when the transmission starts to slip and jerk badly, thinking that it will cure the problem, when in fact the damage was already done.
Hit the nail on the head. Same people will not change oil in their car for 60K miles and blame Ford/GM /Chrysler for a blown engine.
The reason these stories always come up is because people that neglect their cars are very quick to point a finger at something else rather than themselves.
In their mind its the new fluid that killed the tranny, not lack of maintenence.
Also these kind of people usually go for a flush when the transmission starts to slip and jerk badly, thinking that it will cure the problem, when in fact the damage was already done.
Hit the nail on the head. Same people will not change oil in their car for 60K miles and blame Ford/GM /Chrysler for a blown engine.
Originally Posted By: edwardh1
I am all for changing fluid- just not by a flush.
What is so harmful about the transmission using it's own pump to pump fluid through the cooler lines (which it does anyway when it's running) and dumping that fluid into a tank, while a machine simultaneously adds new fluid into the transmission at the exact same rate? It's not actually "flushing" per se, it's just exchanging old fluid with new fluid, like a blood transfusion.
I am all for changing fluid- just not by a flush.
What is so harmful about the transmission using it's own pump to pump fluid through the cooler lines (which it does anyway when it's running) and dumping that fluid into a tank, while a machine simultaneously adds new fluid into the transmission at the exact same rate? It's not actually "flushing" per se, it's just exchanging old fluid with new fluid, like a blood transfusion.
Originally Posted By: edwardh1
I am all for changing fluid- just not by a flush.
Then how? Multiple drain and refills using a expensive ATF is not cost effective and is very ungreen.
Now if the fluid is all the correct type and all one is trying to is a refresh of the ATF, then a different story.
I am all for changing fluid- just not by a flush.
Then how? Multiple drain and refills using a expensive ATF is not cost effective and is very ungreen.
Now if the fluid is all the correct type and all one is trying to is a refresh of the ATF, then a different story.
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I do the cooler line flush method and service it every couple of years. I'd say if you were to have an auxiliary filter (full size) and decided to change that out on an semi-annual basis you could maintain it that way. That would be after a pan drop and main sump filter change.
Some fear the shock of 100% new fluid to the system. The viscosity change will typically be felt if you've got an older, totally hydraulic, trans ...so the perception isn't a total myth.
Some fear the shock of 100% new fluid to the system. The viscosity change will typically be felt if you've got an older, totally hydraulic, trans ...so the perception isn't a total myth.
I know this is an old thread, but I came across it while researching transmission fluid changes.
I have an '04 Chevy Impala 3.4L with ~99k miles. The ATF has never been changed, however, the maintenance schedule in the manual instructs to "change transaxle fluid" @ 100k under normal operating conditions (and 50k for extreme conditions).
Luckily, I have had no issues with the tranny and have been easy on the car when driving, so I'm pretty sure I subscribe to the "normal" group.
My question is, since most of you believe 100k is WAY too long to wait for a ATF change, why does GM use it as their maintenance interval?
Secondly, should I change it now? And if so, by flush or by just dropping the pan (the manual does not specify). It seems that every mechanic I've asked has a different opinion, so I wanted to get you'alls.
I have an '04 Chevy Impala 3.4L with ~99k miles. The ATF has never been changed, however, the maintenance schedule in the manual instructs to "change transaxle fluid" @ 100k under normal operating conditions (and 50k for extreme conditions).
Luckily, I have had no issues with the tranny and have been easy on the car when driving, so I'm pretty sure I subscribe to the "normal" group.
My question is, since most of you believe 100k is WAY too long to wait for a ATF change, why does GM use it as their maintenance interval?
Secondly, should I change it now? And if so, by flush or by just dropping the pan (the manual does not specify). It seems that every mechanic I've asked has a different opinion, so I wanted to get you'alls.
Kestas
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Originally Posted By: ljbrandt
My question is, since most of you believe 100k is WAY too long to wait for a ATF change, why does GM use it as their maintenance interval.
Simple, one reason is they want to give motorists the impression that their vehicle needs little maintenance.
The other is that they don't care if the transmission takes a dump after 120-150K. Quite often, the car owner has lost interest in keeping the car pristine by that time and says, "Oh well, it's an old car", then kicks it to the curb. Transmissions can be kept going a lot longer with good maintenance, even 200K or more.
Why shouldn't you want to change it now? According to a lot of BITOG folk, it's way overdue. At the very least you'd be following the GM schedule.
As far as normal versus extreme conditions go, normal probably means lots of highway miles (little shifting). Extreme would be a lot of stop and go... moreso in hot climates. What kind of driving do you do?
My question is, since most of you believe 100k is WAY too long to wait for a ATF change, why does GM use it as their maintenance interval.
Simple, one reason is they want to give motorists the impression that their vehicle needs little maintenance.
The other is that they don't care if the transmission takes a dump after 120-150K. Quite often, the car owner has lost interest in keeping the car pristine by that time and says, "Oh well, it's an old car", then kicks it to the curb. Transmissions can be kept going a lot longer with good maintenance, even 200K or more.
Why shouldn't you want to change it now? According to a lot of BITOG folk, it's way overdue. At the very least you'd be following the GM schedule.
As far as normal versus extreme conditions go, normal probably means lots of highway miles (little shifting). Extreme would be a lot of stop and go... moreso in hot climates. What kind of driving do you do?
I drive ~125 miles/week, mostly highway to/from work around central Alabama. If I go ahead and change it now, would a pan drop & filter change be sufficient or do I need to get a full flush? The manual does not specify...it just says "change transaxle fluid". Thanks!
Pan drop / filter change should be fine. It would probably be a good idea to repeat the procedure after 20,000 or 30,000 miles since the new fluid will probably clean up some gunk in the transmission.
Welcome to Bitog, ljbrandt. My '05 Caravan says it has lifetime tranny fluid under normal conditions (heed Kestas' advice). Most people here believe in 30 to 50k changes regardless of fluid type or manual recommendations.
For you, a pan drop and filter change is in store. Make sure you access the condition of the pan (scum layer), magnet (normal for it to look like a porcupine from metal bits), and filter.
After that, you will get varying opinions. Some say that on a "neglected" tranny, the half fluid volume replaced in a pan drop is better as it doesn't "shock" the system with too much cleaning action and/or fluid friction modification (the computer will adjust the tranny to the fluid on many). They will say let the fluid clean gently and service it again in 5 to 15 thousand miles.
Others say that a 100% change at this point is fine. Either way, you should do the pan/filter drop now in my opinion. Then, make a decision based on how bad or good things look in there.
FYI, I serviced my Mopar 4 speed tranny every 30K and it still puked at 100k. It has a questionable reputation and I got one of the clunkers.
For you, a pan drop and filter change is in store. Make sure you access the condition of the pan (scum layer), magnet (normal for it to look like a porcupine from metal bits), and filter.
After that, you will get varying opinions. Some say that on a "neglected" tranny, the half fluid volume replaced in a pan drop is better as it doesn't "shock" the system with too much cleaning action and/or fluid friction modification (the computer will adjust the tranny to the fluid on many). They will say let the fluid clean gently and service it again in 5 to 15 thousand miles.
Others say that a 100% change at this point is fine. Either way, you should do the pan/filter drop now in my opinion. Then, make a decision based on how bad or good things look in there.
FYI, I serviced my Mopar 4 speed tranny every 30K and it still puked at 100k. It has a questionable reputation and I got one of the clunkers.
Many people mistakenly blame a "flush" for killing their trans. It's an easy mistake to make. I have searched far and wide for years and NEVER seen any type of trans fluid machine that does any sort of 'power flush'. Seems everyone uses passive machines, and they won't hurt a thing. But you still need to drop the pan and change the filter occasionally.
Due to the ability to modulate their pressures over a really wide range, a modern auto can run a LONG time on completely shot fluids, all the while chewing its wear parts to pieces.
We run our 4L80E equipped service vans to 200k miles routinely without anything but normal servicing. We have yet to see a 4L65E fail in our service. All city, no highway work at all.
Due to the ability to modulate their pressures over a really wide range, a modern auto can run a LONG time on completely shot fluids, all the while chewing its wear parts to pieces.
We run our 4L80E equipped service vans to 200k miles routinely without anything but normal servicing. We have yet to see a 4L65E fail in our service. All city, no highway work at all.
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