Author Topic: Flushing kill older auto trans?  (Read 2993 times)

Offline Skunksmash

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Flushing kill older auto trans?
« on: June 27, 2011, 05:42:16 pm »
Hi all. I have heard that getting your transmission flushed can hurt it, if its got a lot of miles on it. Is this true? You're supposed to flush cause if not then you're only changing like 1/4 of the fluid. Much still remains in the torque converter and in the trans.

Offline Irish_Alley

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Re: Flushing kill older auto trans?
« Reply #1 on: June 27, 2011, 06:18:55 pm »
if heard that also. one reason is that new fluid is too thick to properly lubricate the worn parts. and also just like how an engine stores up crud and crap the trans does this and a flush might not remove all the crap and causes more problems. idk i can’t help out with any of this they kind of make sense but who knows. i can say a couple things 1 anything mechanical can’t heal its self even with a bath you have to remove the worn parts and replace them. Also when i had problems with my mom’s e150 Trans slipping i changed the fluid and used Lucas trans fluid it helped out and is still running strong
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Offline VileZambonie

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Re: Flushing kill older auto trans?
« Reply #2 on: June 27, 2011, 10:12:22 pm »
Let's put it this way, If you flush a transmission that's about to take a dive you will find it doing more harm than good. If it's just do for a service yes the flush is the ideal method.
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Offline bobcooter

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Re: Flushing kill older auto trans?
« Reply #3 on: June 29, 2011, 08:57:38 pm »
Tha'ts right. If it has a lot of miles on it but it's been serviced regularly it should'nt be a problem. If it's been a lot of miles between servicing and you flush it, you can probably kiss it good by. My TH-400 got to where it didn't want to back up in cold weather this winter. I drained the fluid and changed the filter. Then I added two jugs of Lucas Transmissiom Fix and filtered my old fluid and put it back in the transmission with no problems.
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Offline royo

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Re: Flushing kill older auto trans?
« Reply #4 on: July 01, 2011, 10:09:55 am »
Hi all. I have heard that getting your transmission flushed can hurt it, if its got a lot of miles on it. Is this true? You're supposed to flush cause if not then you're only changing like 1/4 of the fluid. Much still remains in the torque converter and in the trans.
Is the fluid black or smell burnt? if not just change the filter