When performing a simple drain & fill with engine / tranny warm - do you replace ATF in a 1:1 ratio of what you took out OR do you replace slightly less using cold ATF ...Not quite sure how this works - but I believe temperature of the ATF plays a role in how much to replace ?
ATF Drain & Fill When Warm ?
- Thread starter ChrisD46
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I usually knew how much would drain out and just replace that amount. If it was 6 liters then 6 went back in.
Now if I had a gasket leak then I would buy an extra bottle of ATF.
Now if I had a gasket leak then I would buy an extra bottle of ATF.
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
Originally Posted By: demarpaint
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
+1
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
+1
Easy way might be to use one of the cheap digital kitchen scales. Get the mass of the fluid removed. Refill with that much new. Temperature becomes irrelevant.
I do it just replace the same amount but check dipstick and then recheck after driving for the first time getting everything hot.
Originally Posted By: RamFan
Drain it cold and replace it with what came out.
Great idea. That method insures that any agglomerated particulate is all settled out on the bottom in a paste/mud type of substance so as the fluid drains the lighter stuff is going to escape first because it flows faster.
Engine oil, tranny fluid and power steering fluid should all the serviced within moments of shutting off the vehicle. This method insures the fluids have been mixed up really well and all the agglomerated particulate is more able to be removed.
Cold fluid exchanges really make no sense.
Drain it cold and replace it with what came out.
Great idea. That method insures that any agglomerated particulate is all settled out on the bottom in a paste/mud type of substance so as the fluid drains the lighter stuff is going to escape first because it flows faster.
Engine oil, tranny fluid and power steering fluid should all the serviced within moments of shutting off the vehicle. This method insures the fluids have been mixed up really well and all the agglomerated particulate is more able to be removed.
Cold fluid exchanges really make no sense.
Originally Posted By: demarpaint
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
Agreed. Most of us bitogers just have a natural sensibility when it comes to fluids.
Some don't have it and it becomes painfully obvious. Good for a laugh though
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
Agreed. Most of us bitogers just have a natural sensibility when it comes to fluids.
Some don't have it and it becomes painfully obvious. Good for a laugh though
Originally Posted By: Clevy
Originally Posted By: demarpaint
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
Agreed. Most of us bitogers just have a natural sensibility when it comes to fluids.
Some don't have it and it becomes painfully obvious. Good for a laugh though
Yes Clevy! It is painfully obvious how brilliant you are. Seriously, you are a smart guy Clevy but you are constantly making it a point to let people know that. Just chill and people respect that more.
Sorry to be off topic, but my conscience was speaking. No beef.
And to add. this is a place where people should not have to be afraid to ask questions, this is a place to learn. I think you and I both know there are people on this site that can put us to shame with the knowledge they have.
OK...I'm finished.
Originally Posted By: demarpaint
I prefer to do it warm, drain it, measure it, replace it, then verify the level with the dipstick. There is always the possibility a small amount is lost, using the dipstick eliminates that.
Agreed. Most of us bitogers just have a natural sensibility when it comes to fluids.
Some don't have it and it becomes painfully obvious. Good for a laugh though
Yes Clevy! It is painfully obvious how brilliant you are. Seriously, you are a smart guy Clevy but you are constantly making it a point to let people know that. Just chill and people respect that more.
Sorry to be off topic, but my conscience was speaking. No beef.
And to add. this is a place where people should not have to be afraid to ask questions, this is a place to learn. I think you and I both know there are people on this site that can put us to shame with the knowledge they have.
OK...I'm finished.
Last edited:
Originally Posted By: Clevy
Originally Posted By: RamFan
Drain it cold and replace it with what came out.
Great idea. That method insures that any agglomerated particulate is all settled out on the bottom in a paste/mud type of substance so as the fluid drains the lighter stuff is going to escape first because it flows faster.
Engine oil, tranny fluid and power steering fluid should all the serviced within moments of shutting off the vehicle. This method insures the fluids have been mixed up really well and all the agglomerated particulate is more able to be removed.
Cold fluid exchanges really make no sense.
I am betting in my case, my Magnefine filter is catching almost everything so nothing to settle.
Originally Posted By: RamFan
Drain it cold and replace it with what came out.
Great idea. That method insures that any agglomerated particulate is all settled out on the bottom in a paste/mud type of substance so as the fluid drains the lighter stuff is going to escape first because it flows faster.
Engine oil, tranny fluid and power steering fluid should all the serviced within moments of shutting off the vehicle. This method insures the fluids have been mixed up really well and all the agglomerated particulate is more able to be removed.
Cold fluid exchanges really make no sense.
I am betting in my case, my Magnefine filter is catching almost everything so nothing to settle.
Originally Posted By: RamFan
Drain it cold and replace it with what came out.
This is what I do.
Drain it cold and replace it with what came out.
Would this make sense : If you drain ATF while it is warm (not hot) it will flow out a little better - however perhaps better to under fill slightly with cold ATF , drive it until hot and then check it again using the hot mark on the dipstick . I suppose that's why there is a cold and hot mark on the dipstick as what ever the temp of the ATF is coming out is NOT the same temp ATF as what you put back in .
Originally Posted By: ChrisD46
Would this make sense : If you drain ATF while it is warm (not hot) it will flow out a little better - however perhaps better to under fill slightly with cold ATF , drive it until hot and then check it again using the hot mark on the dipstick . I suppose that's why there is a cold and hot mark on the dipstick as what ever the temp of the ATF is coming out is NOT the same temp ATF as what you put back in .
Yes. At the end of the day the best measurement is while hot. That does not mean you must drain and fill while hot, rather any adjustments made should be made while the fluid is hot (if the dipstick doesn't have a cold range). If there is no dipstick at all, I stand by my previous statement that draining or extracting cold fluid and replacing it with the same quantity of new cold fluid is the best way to ensure proper trans level.
Would this make sense : If you drain ATF while it is warm (not hot) it will flow out a little better - however perhaps better to under fill slightly with cold ATF , drive it until hot and then check it again using the hot mark on the dipstick . I suppose that's why there is a cold and hot mark on the dipstick as what ever the temp of the ATF is coming out is NOT the same temp ATF as what you put back in .
Yes. At the end of the day the best measurement is while hot. That does not mean you must drain and fill while hot, rather any adjustments made should be made while the fluid is hot (if the dipstick doesn't have a cold range). If there is no dipstick at all, I stand by my previous statement that draining or extracting cold fluid and replacing it with the same quantity of new cold fluid is the best way to ensure proper trans level.
Originally Posted By: ChrisD46
Would this make sense : If you drain ATF while it is warm (not hot) it will flow out a little better - however perhaps better to under fill slightly with cold ATF , drive it until hot and then check it again using the hot mark on the dipstick . I suppose that's why there is a cold and hot mark on the dipstick as what ever the temp of the ATF is coming out is NOT the same temp ATF as what you put back in .
That's pretty much exactly how you should do it.
Draining the fluid after it is warm is better, the particulates are still in suspension and not settled to the bottom of the pan. Take the car for a short drive, turn it off for about 10 minutes and do your extraction. Measure the amount taken out add it back with fresh fluid, then check the fluid as per the owners manual using the dipstick. That method is fool proof. You'll always be a little under, since you're not going to be able to measure with 100% accuracy the amount you extracted. There will be AFT in the jug or pan you didn't get out, some in the hose etc. Don't get me wrong you'll be close, but checking with the dipstick according to the OM is fool proof. Cold fluid doesn't flow as well and any particles have settled out of suspension.
I've done it this way for many years, and always had to add a slight amount, no matter how hard I tried to contain and measure every drop I removed. Opinions vary.
Would this make sense : If you drain ATF while it is warm (not hot) it will flow out a little better - however perhaps better to under fill slightly with cold ATF , drive it until hot and then check it again using the hot mark on the dipstick . I suppose that's why there is a cold and hot mark on the dipstick as what ever the temp of the ATF is coming out is NOT the same temp ATF as what you put back in .
That's pretty much exactly how you should do it.
Draining the fluid after it is warm is better, the particulates are still in suspension and not settled to the bottom of the pan. Take the car for a short drive, turn it off for about 10 minutes and do your extraction. Measure the amount taken out add it back with fresh fluid, then check the fluid as per the owners manual using the dipstick. That method is fool proof. You'll always be a little under, since you're not going to be able to measure with 100% accuracy the amount you extracted. There will be AFT in the jug or pan you didn't get out, some in the hose etc. Don't get me wrong you'll be close, but checking with the dipstick according to the OM is fool proof. Cold fluid doesn't flow as well and any particles have settled out of suspension.
I've done it this way for many years, and always had to add a slight amount, no matter how hard I tried to contain and measure every drop I removed. Opinions vary.
I do it cold so I don't burn my fingers on hot bolts, oil, or the pan. It's already enough of a circus doing it on ramps or stands with limited clearance on my garage floor. Less spillage makes me look like a pro.
ATF is thin, it drips fine when cold, IMO. If I have to put my (goggled) face under there to make sure the filter o-ring came off cleanly, I don't need hot ATF all in my hair.
My vote for cold, a vote for wussiness.
ATF is thin, it drips fine when cold, IMO. If I have to put my (goggled) face under there to make sure the filter o-ring came off cleanly, I don't need hot ATF all in my hair.
My vote for cold, a vote for wussiness.
I let the tranny get to about 120F and drain. I've already filled the sink with hot water and the new fluid is taking a nice warm bath. I measure what came out and overfill slightly. MINi uses a overflow tube for setting the level so this works great. The Buick 4L60E gets under filled and brought up to full.
The MINI doesn't have a dipstick so this replicates the factory procedure. The warmed fluid also fills faster through the small filler bolt opening.
The MINI doesn't have a dipstick so this replicates the factory procedure. The warmed fluid also fills faster through the small filler bolt opening.
Originally Posted By: Donald
I do it just replace the same amount but check dipstick and then recheck after driving for the first time getting everything hot.
Ditto but do it warm...
I do it just replace the same amount but check dipstick and then recheck after driving for the first time getting everything hot.
Ditto but do it warm...
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