moonlight
08-12-2009, 05:31 PM
My trusted independent mechanic has recommended a power flush of the transmission with next regular service on my 07 Sonata 2.4L GL automatic with 33k even though the tran fluid is still nice and pink.
However I have read:
"The only ones who recommend you get a transmission fluid FLUSH are the people who make the transmission flush machines and the shops who buy them. As has been stated many times and in many places no automotive manufacturer recommends a transmission fluid as a regular service. In fact General Motors, Chrysler, Ford and most of the import manufacturers recommend AGAINST it, going as far as voiding the new car warranty if it is done.
All that is recommended is a regular automatic transmission service which entails dropping the transmission pan, replacing the transmission filter where applicable, draining the torque converter where applicable and refilling with fresh, new automatic transmission fluid."
See this (http://autotechrepair.suite101.com/article.cfm/two_fluid_flushing_questions) and this (http://autotechrepair.suite101.com/article.cfm/040206).
This makes sense to me because:
1) In a power flush, as I understand it, the drain plug is not pulled. But the drain plug has a strong magnet on the end to pick up any junk that might hurt the filter. By cleaning the plug, the junk is removed.
2) A power flush could hurt the filter directly or by pushing junk into it and in either case it would not be discovered since the Sonata tran filter is not accessible under normal servicing conditions.
3) The chemicals used in a power flush and the power itself could hurt the mechanism.
4) As long as the T fluid is not very dirty, a drain and replace will replace at least 50% of the T fluid and if it really needs to have more replaced after a second drain, over 75% will be replaced.
5) Finally the flush uses a lot more fluid, which would be bad for the environment.
I sent this question to Hyundai Customer Service; their answer was that I should consult my local dealer!! That's a joke.
What do you think?
However I have read:
"The only ones who recommend you get a transmission fluid FLUSH are the people who make the transmission flush machines and the shops who buy them. As has been stated many times and in many places no automotive manufacturer recommends a transmission fluid as a regular service. In fact General Motors, Chrysler, Ford and most of the import manufacturers recommend AGAINST it, going as far as voiding the new car warranty if it is done.
All that is recommended is a regular automatic transmission service which entails dropping the transmission pan, replacing the transmission filter where applicable, draining the torque converter where applicable and refilling with fresh, new automatic transmission fluid."
See this (http://autotechrepair.suite101.com/article.cfm/two_fluid_flushing_questions) and this (http://autotechrepair.suite101.com/article.cfm/040206).
This makes sense to me because:
1) In a power flush, as I understand it, the drain plug is not pulled. But the drain plug has a strong magnet on the end to pick up any junk that might hurt the filter. By cleaning the plug, the junk is removed.
2) A power flush could hurt the filter directly or by pushing junk into it and in either case it would not be discovered since the Sonata tran filter is not accessible under normal servicing conditions.
3) The chemicals used in a power flush and the power itself could hurt the mechanism.
4) As long as the T fluid is not very dirty, a drain and replace will replace at least 50% of the T fluid and if it really needs to have more replaced after a second drain, over 75% will be replaced.
5) Finally the flush uses a lot more fluid, which would be bad for the environment.
I sent this question to Hyundai Customer Service; their answer was that I should consult my local dealer!! That's a joke.
What do you think?