Change Trans. Fluid.....Yes or No
Thread Starter
Instructor
Joined: Jun 2002
Posts: 134
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Change Trans. Fluid.....Yes or No
I've read here that it's a good thing to change all fluids when you first aquire a new car and I agree, but I have also heard that changing the tranny fluid is not really recomended for cars with higher mileage and that it can actually induce problems especially if you flush. My car has 79,000 miles on it and it is an 85' L98. Any thoughts?
Melting Slicks
Joined: Mar 2001
Posts: 2,107
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From: Austin TX
Re: Change Trans. Fluid.....Yes or No (champs_97)
Yea, I have been wondering the same thing too. I was thinking about just draining and adding. Maybe do this every year instead of a complete flush. I have 124K miles.....
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Re: Change Trans. Fluid.....Yes or No (champs_97)
Here is my take:
Bought the car in 2001 with 117k on the clock
In Jan of 2002 replaced all the fluids because I had no clue as to the maintenance done before (120K)
At the time of the full change the car seemed happier with the fresh fluids (including synthetic motor oil).
I now have 128K and have experienced no transmission or differential problems. I'm sticking with synthetic motor oil (Mobil 1) because it doesn't leak any more than it did with dino oil. It seems to run better with the synthetic.
JMHO
Bought the car in 2001 with 117k on the clock
In Jan of 2002 replaced all the fluids because I had no clue as to the maintenance done before (120K)
At the time of the full change the car seemed happier with the fresh fluids (including synthetic motor oil).
I now have 128K and have experienced no transmission or differential problems. I'm sticking with synthetic motor oil (Mobil 1) because it doesn't leak any more than it did with dino oil. It seems to run better with the synthetic.
JMHO
Race Director
Joined: Aug 2000
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Re: Change Trans. Fluid.....Yes or No (champs_97)
I dont flush the tranny but simply drop the pan,let it drain,replace filter,fill back up etc.
Doing this now will also allow you to see if theres any metal shavings/shrapnel in the pan or burnt fluid.
If so,the tranny will go eventually.
It should not hurt anything to change the fluids.In my cases,it made the tranny shift better and run good again.I have heard the stories about people replacing the fluid/filter then afterwards the tranny went boom.I still think it was on its way out eventually.
:)
Doing this now will also allow you to see if theres any metal shavings/shrapnel in the pan or burnt fluid.
If so,the tranny will go eventually.
It should not hurt anything to change the fluids.In my cases,it made the tranny shift better and run good again.I have heard the stories about people replacing the fluid/filter then afterwards the tranny went boom.I still think it was on its way out eventually.
:)
Melting Slicks
Joined: Jan 2000
Posts: 3,418
Likes: 1
From: NW Chicago Suburbs
Re: Change Trans. Fluid.....Yes or No (Bill's86Coupe)
I have heard the stories about people replacing the fluid/filter then afterwards the tranny went boom.I still think it was on its way out eventually.
Eric
Burning Brakes
Joined: May 2002
Posts: 1,143
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From: CASTLE ROCK CO
Re: Change Trans. Fluid.....Yes or No (silver & red CE)
I agree with Siler&Red. I flushed mine by taking the upper trans fitting off, connecting a hose and clamp to the line, putting the hose into an empty laundry detergent container(holds about 2 1/2 Gals.) Opened 12 Quarts of Dextron III . Started the car as it pumped out I poured in. By the time I got to the 11th quart the fluid coming out was clean and red. Shut it off ,reconnected the line. Topped it off. Later I will change the trans gasket and filter. That should only be around 4 quarts or so.
Team Owner
Joined: Apr 2000
Posts: 27,818
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From: CT
Re: Change Trans. Fluid.....Yes or No (Bill's86Coupe)
I dont flush the tranny but simply drop the pan,let it drain,replace filter,fill back up etc.
Doing this now will also allow you to see if theres any metal shavings/shrapnel in the pan or burnt fluid.
If so,the tranny will go eventually.
It should not hurt anything to change the fluids.In my cases,it made the tranny shift better and run good again.I have heard the stories about people replacing the fluid/filter then afterwards the tranny went boom.I still think it was on its way out eventually.
:)
Doing this now will also allow you to see if theres any metal shavings/shrapnel in the pan or burnt fluid.
If so,the tranny will go eventually.
It should not hurt anything to change the fluids.In my cases,it made the tranny shift better and run good again.I have heard the stories about people replacing the fluid/filter then afterwards the tranny went boom.I still think it was on its way out eventually.
:)
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Joined: Jun 2002
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From: Maryville Tn
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Re: Change Trans. Fluid.....Yes or No (champs_97)
You shouldn't have any problems when you change your trans fluid (stay away from the flushing agents). I changed mine when I bought my '85 with 111,000 miles on it. I've had no problems and no leaks. When in doubt, change it out! :yesnod:
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Le Mans Master
Joined: Apr 2000
Posts: 6,341
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From: Shelton CT
Re: Change Trans. Fluid.....Yes or No (H P Bushrod)
I had mine changed at 70K, 90K and just now at 103K.. No problems (knock on wood).
Every time I had the shop drop the pan and check for metal shavings. Nothing.. :smash:
Every time I had the shop drop the pan and check for metal shavings. Nothing.. :smash:
Le Mans Master
Joined: Apr 2000
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From: Manassas VA
Re: Change Trans. Fluid.....Yes or No (Justin1984)
I have a good friend who has worked on a bench rebuilding transmissions for 25 + years. He believes that as long as you change the filter a flush will not hurt anything. However he also says its not necessary. Just change the filter and the 4 or 5 qts of fluid every 15,000 miles and enough of the fluid will be changed.
Melting Slicks
Joined: Jan 2000
Posts: 3,418
Likes: 1
From: NW Chicago Suburbs
Re: Change Trans. Fluid.....Yes or No (Justin1984)
what is everybody here running in their 700R4's?
Eric
Drifting
Joined: Nov 1999
Posts: 1,281
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From: San Diego Ca
Re: Change Trans. Fluid.....Yes or No (OleDog)
I agree with Siler&Red. I flushed mine by taking the upper trans fitting off, connecting a hose and clamp to the line, putting the hose into an empty laundry detergent container(holds about 2 1/2 Gals.) Opened 12 Quarts of Dextron III . Started the car as it pumped out I poured in. By the time I got to the 11th quart the fluid coming out was clean and red. Shut it off ,reconnected the line. Topped it off. Later I will change the trans gasket and filter. That should only be around 4 quarts or so.
Racer
Joined: May 2001
Posts: 452
Likes: 0
From: Griffin GA
Re: Change Trans. Fluid.....Yes or No (champs_97)
Do you change your Oil? Then Change the trans fluid and the filter. It ia also a good idea to change the rear end grease as well. If you use a syn you can even pick up a couple of HP. (As stated by Popular HotRoading TV).
Advanced
Joined: Aug 2001
Posts: 74
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Re: Change Trans. Fluid.....Yes or No (yoslambo1@cs.com)
I was reading the other day in a magazine (Corvette Fever, I think) where the writer thought this should be changed every 2 years regardless of miles due to condensation/water.
Any consensus out there as to whether 2 years is about right or if its really the mileage that counts?
For what it is worth, I was told by someone that 12,000 mi is about the right interval....
Any consensus out there as to whether 2 years is about right or if its really the mileage that counts?
For what it is worth, I was told by someone that 12,000 mi is about the right interval....
Pro
Joined: Feb 2001
Posts: 662
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From: Denver CO
Re: Change Trans. Fluid.....Yes or No (Dutch W.)
My experience along with the experience of friends in the tranny biz all agree that tranny fluid is very fickle....If the fluid is old crap than you should leave it old and crappy. If it looks and SMELLS fair, but in need of a change you may be OK. Old crappy fluid being replaced partially by the 4 qts. in the pan will turn the remaining 7.5 qts. into a solvent that will induce a quick wear to the clutch faces. 12k is the best change interval for a tranny. Fluid that has a 100k or so on it no longer has the same properties of new fluid and they don't mix with benefitial results. How does your fluid look? smell? miles?
Also, the enemy of any auto tranny is heat, old fluid does not dissapate heat very well. Thus causing wear to occur at a much higher rate.
Just MHO.
Good luck,
Robert
Also, the enemy of any auto tranny is heat, old fluid does not dissapate heat very well. Thus causing wear to occur at a much higher rate.
Just MHO.
Good luck,
Robert
