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Changing transmission fluid?

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Old Aug 11, 2009 | 07:56 PM
  #1  
67kjcoupe's Avatar
67kjcoupe
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From: GA
Default Changing transmission fluid?

Hey everybody
btw if ya havent noticed im new
my dad just told me about this site yesterday
....its awesome haha

but yea
just finished up the body work/gauges/etc etc you know the story
and im doing a couple small things gettin it ready
oil change, transmission fluid and filter change, rear end dope
and i had a quick question

i have heard that on older vehicles
changing the transmission fluid can be somewhat of a bad idea
i have heard from a couple different people
that the vehicle kind of adjusts to the fluid almost
and changing it can start causing problems

ever had it happen?
heard that?

bc personally i dont like my tranny fluid looking like 5w30 haha
plus the speedometer cable gear broke inside
so im wanting to get in there and check everything out

i was planning on doing this tomorrow
but once again at the parts store i had someone tell me that about them
then i remembered dad telling me about this site
so well here i am

any help?
Old Aug 11, 2009 | 10:16 PM
  #2  
2+2GT's Avatar
2+2GT
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Transmissions typically will run better with new, uncontaminated fluid.
Old Aug 11, 2009 | 11:06 PM
  #3  
67kjcoupe's Avatar
67kjcoupe
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thats what i always thought
but i figured it never hurt to ask
Old Aug 12, 2009 | 02:45 AM
  #4  
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rmodel65
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what part of Georgia are you from??
Old Aug 12, 2009 | 01:53 PM
  #5  
67kjcoupe's Avatar
67kjcoupe
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ringgold ga
Old Aug 12, 2009 | 02:01 PM
  #6  
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unit91
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I was told to let the fluid drain out on its own, and not to have the transmission 'flushed' because the pressure from the flushing might loosen some pieces of crap in there that may not all come out. Ever heard that? Experienced that? Any turth to that?
Old Oct 14, 2009 | 08:08 PM
  #7  
04Comp-orange GT's Avatar
04Comp-orange GT
 
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I want to change mine too but i'm not sure what to do.
Old Oct 15, 2009 | 02:09 AM
  #8  
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hiboostwoody
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If your tranny fluid is the color of used motor oil, you are probably too late. The problem changing transmission fluid in cars with marginal transmissions in the first place is that tranny fluid is very high detergent so when you put the new stuff in it basically cleans all the crap out that is acting like "glue" to hold pressures up so that the tranny will work. The Power flushing is ALWAYS a bad idea for this reason also. I am the head tech for 4 transmission shops and we LOVE the jiffy lube places that sell the power flush because usually within about a week we will see the car in our shop for a new transmission.

Don't get me wrong, servicing your transmission should be done at regular intervals(about 30k miles) just like changing your engine oil. BUT if you drop the pan and see a lot stuff in the bottom that looks like very find black dust, your best bet is to just put the pan back on and pour the OLD fluid back into the transmission. This will usually get you by for a while.
Old Oct 15, 2009 | 02:19 AM
  #9  
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hiboostwoody
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Originally Posted by 04Comp-orange GT
I want to change mine too but i'm not sure what to do.
Take the bolts out that are holding the transmission pan to the transmission. If you are lucky, your pan will have a drain plug but most don't so be prepared to make a big mess and end up wearing a lot of the fluid, espescially if you are doing this on your back. Once you have the pan off, take the filter out and either replace it with a new one or, if your filter is a screen type, you can use brake cleaner in an aerosol can to clean the screen. Then put it all back together with a new gasket and refill it through the dipstick tube. Most of the Ford passenger car transmissions will take between 5 and 7 quarts of fluid to refill them after a service but the proper way to do it is to put in about 3 1/2 quarts, start the car, run the shifter through the gears (PUT THE EMERGENCY BRAKE ON FIRST!) taking time to pause for a few seconds in every gear, the check the fluid level with the car running in park. After you have the fluid filled to marks on the dipstick, take it for a spin around the block then recheck the fluid level.
Old Oct 15, 2009 | 03:32 PM
  #10  
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Originally Posted by unit91
I was told to let the fluid drain out on its own, and not to have the transmission 'flushed' because the pressure from the flushing might loosen some pieces of crap in there that may not all come out. Ever heard that? Experienced that? Any turth to that?
Only flush one if it's contaminated. Of course if it's contaminated with much of anything other than trans fluid it's probably too late... One problem with flushing a trans is the fact that the dirt and crud will forever stay in the oil pan. It's physically impossible for a flush to remove it and I'd love a "word" in private with the idiots that sell this snake oil with the promise of miracles. Plus, only when you remove the pan can you actually "see" what shape things are in. If it's reasonably clean (light black film on the bottom of the pan which doesn't hide the silver color of the pan at worst), clean it up and go back together with new parts. If it's much more than that on the bottom of the pan, ie, metal shavings or a thick black film which hides the color of the pan, follow the previous post and put it back together as is and drive it carefully with your wrecker driver on speed dial. See, with a flush, you'd never know.



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