to pretty much get all the old fluid out of a 12 quart transmission. The transmission is a 4L60 out of a 03 Yukon. I get about 4 quarts out of each drain. I just want to see if it would be easier to do a bunch of drain and fills vs paying for a t tec flush?
How many drain and fills would it take..
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Each time you replace 4 qts, you end up with 1/3 new and 2/3 old oil.
Let's call the oil you want to get rid of original oil.
Since your interest is in the original oil, not the oil you just added last 4 qt change you can figure it this way...
1st 4 qt change you have 67% original oil
2nd 4 qt change you have 67& of the results of the last batch in the engine. The last batch was 67% original, so you have 0.67 x 0.67 = 0.67^2 = 0.45 or 45% old oil.
After 3 changes, 12 qts of new oil you would have 0.67^3 = 30% of the original oil.
Use 24 qts total (6 operations) and you would have 0.67^6 = 9% of your original oil left.
Let's call the oil you want to get rid of original oil.
Since your interest is in the original oil, not the oil you just added last 4 qt change you can figure it this way...
1st 4 qt change you have 67% original oil
2nd 4 qt change you have 67& of the results of the last batch in the engine. The last batch was 67% original, so you have 0.67 x 0.67 = 0.67^2 = 0.45 or 45% old oil.
After 3 changes, 12 qts of new oil you would have 0.67^3 = 30% of the original oil.
Use 24 qts total (6 operations) and you would have 0.67^6 = 9% of your original oil left.
do you have a drain plug or do you have to drop the pan? That should make your decision much easier. Also if you are going to take it somewhere then watch them do it to make sure that 1. they are doing it right 2. they even perform the service.
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Originally Posted By: Barkleymut
do you have a drain plug or do you have to drop the pan? That should make your decision much easier. Also if you are going to take it somewhere then watch them do it to make sure that 1. they are doing it right 2. they even perform the service.
I heard that. Lazy people and thieves abound these days.
do you have a drain plug or do you have to drop the pan? That should make your decision much easier. Also if you are going to take it somewhere then watch them do it to make sure that 1. they are doing it right 2. they even perform the service.
I heard that. Lazy people and thieves abound these days.
Originally Posted By: Barkleymut
do you have a drain plug or do you have to drop the pan? That should make your decision much easier. Also if you are going to take it somewhere then watch them do it to make sure that 1. they are doing it right 2. they even perform the service.
I would get myself a fluid extractor! It makes replacing transmission fluid a relatively quick task.
do you have a drain plug or do you have to drop the pan? That should make your decision much easier. Also if you are going to take it somewhere then watch them do it to make sure that 1. they are doing it right 2. they even perform the service.
I would get myself a fluid extractor! It makes replacing transmission fluid a relatively quick task.
Why not do a cooling line flush. You can do it in much less time than many drain & fills. The more expensive the ATF is the more cost effective it is. The least amount of mixing old and new ATF is when you drain the pan first then immediately do the cooling line flush. Its documented on the Amsoil website and also on this website. A cooling line flush should take the capacity + 1 QT to make sure.
A flush machine at a car shop is so the mechanic can do something else for 20 minutes, but certainly not a better flush. The pump in your transmission pushes the ATF through the transmission, all the flush machine does is to keep the pan filled with new ATF.
A flush machine at a car shop is so the mechanic can do something else for 20 minutes, but certainly not a better flush. The pump in your transmission pushes the ATF through the transmission, all the flush machine does is to keep the pan filled with new ATF.
Originally Posted By: mcrn
Thank you very much XS650 that is exactly what I was looking for!
someone wrote an excel program to figure this stuff out. It's buried somewhere in these forums.
Thank you very much XS650 that is exactly what I was looking for!
someone wrote an excel program to figure this stuff out. It's buried somewhere in these forums.
Thanks everyone! Barkle I do have a drain plug! Woohoo! And D-roc I am leaning towards the 6 drops at this time, although I might change my mind. A friend of mine works at a shop with this machine so I would trust him to put my fluid in and actually do the service. I just like to do things like this myself. The feeling of doing it yourself just feels good. Although I think the flush might be a better result when all is said and done. And as far as the cost goes the fluid I am using right now is only a little over $3 a quart, so not too bad. Thanks again!
You would be better off doing a cooling line flush yourself (after a pan drain) using Amsoil at $8 or $9 QT. You will get it done with 12-13 QTs and have the best ATF in your transmission that should go 50K severe and 100K normal. You won't get that with your $3 QT ATF.
My guess is the total cost of all your drain and refills will be not that much from one cooling line flush using a top rated ATF like Amsoil.
I think a single drain and refill every 15K - 25K are good way to get some new fluid in and old fluid (with wear metals out) but multiple drain and refills are not a good way to exchange fluid (and is not a very green way either).
My guess is the total cost of all your drain and refills will be not that much from one cooling line flush using a top rated ATF like Amsoil.
I think a single drain and refill every 15K - 25K are good way to get some new fluid in and old fluid (with wear metals out) but multiple drain and refills are not a good way to exchange fluid (and is not a very green way either).
Use DEXVI not Amsoil....cheaper and will do just fine and last just as long. 4-4qt drin fills gets you 80% new fluid 5-4 qt drain/fills gets you 87% new fluid. 6 gets you 91%. 7 gets you 94%. I do this on all my vehicles. Never a trans failure yet. BTW, I have a 2006 YukonXL 4L60e with DEXVI and it runs fine. WHen I do my home "flush" I drive a day between each drain fill to mix it up. Takes a week to complete. I use a fluid extractor because I have no drain bolt. Easy peasy. I did get one dealer flush...no difference in performance than by DIY.
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Originally Posted By: PT1
Use DEXVI not Amsoil....cheaper and will do just fine and last just as long. 4-4qt drin fills gets you 80% new fluid 5-4 qt drain/fills gets you 87% new fluid. 6 gets you 91%. 7 gets you 94%. I do this on all my vehicles. Never a trans failure yet. BTW, I have a 2006 YukonXL 4L60e with DEXVI and it runs fine. WHen I do my home "flush" I drive a day between each drain fill to mix it up. Takes a week to complete. I use a fluid extractor because I have no drain bolt. Easy peasy. I did get one dealer flush...no difference in performance than by DIY.
Not sure I agree, Amsoil ATF out performs all other ATF tests that I have looked at. If you run your ATF 15K-20K it might not matter, run it 50K to 100K and it will matter.
Have you some tests you can point to that show DEXVI performs better than Amsoil ATF?
Use DEXVI not Amsoil....cheaper and will do just fine and last just as long. 4-4qt drin fills gets you 80% new fluid 5-4 qt drain/fills gets you 87% new fluid. 6 gets you 91%. 7 gets you 94%. I do this on all my vehicles. Never a trans failure yet. BTW, I have a 2006 YukonXL 4L60e with DEXVI and it runs fine. WHen I do my home "flush" I drive a day between each drain fill to mix it up. Takes a week to complete. I use a fluid extractor because I have no drain bolt. Easy peasy. I did get one dealer flush...no difference in performance than by DIY.
Not sure I agree, Amsoil ATF out performs all other ATF tests that I have looked at. If you run your ATF 15K-20K it might not matter, run it 50K to 100K and it will matter.
Have you some tests you can point to that show DEXVI performs better than Amsoil ATF?
Dex VI is a synthetic blend, not a full synthetic.
Mobil-1, RP, RedLine (I think) and a few others offer full synthetic ATF; all cheaper than Amsoil.
Use what you can afford and are comfortable with.
Mobil-1, RP, RedLine (I think) and a few others offer full synthetic ATF; all cheaper than Amsoil.
Use what you can afford and are comfortable with.
Do a flush.
Originally Posted By: Donald
Originally Posted By: PT1
Use DEXVI not Amsoil....cheaper and will do just fine and last just as long. 4-4qt drin fills gets you 80% new fluid 5-4 qt drain/fills gets you 87% new fluid. 6 gets you 91%. 7 gets you 94%. I do this on all my vehicles. Never a trans failure yet. BTW, I have a 2006 YukonXL 4L60e with DEXVI and it runs fine. WHen I do my home "flush" I drive a day between each drain fill to mix it up. Takes a week to complete. I use a fluid extractor because I have no drain bolt. Easy peasy. I did get one dealer flush...no difference in performance than by DIY.
Not sure I agree, Amsoil ATF out performs all other ATF tests that I have looked at. If you run your ATF 15K-20K it might not matter, run it 50K to 100K and it will matter.
Have you some tests you can point to that show DEXVI performs better than Amsoil ATF?
DexVI is the only ATF speced by GM for their transmissions. It is the backwards compatable ATF for all Dexron ATF's. GM has done all the testing. Amsoil is not licensed by GM for that application. Then add the fact that you can get it for 1/3 the price and GM specs it for 50k severe and 100k normal service in a 2006 4L60e what is the better value? So you can do three 30k OCI's for the same price as 1 Amsoil OCI. Sorry, I'm going with DEXVI. Why would anyone pay 3x for an unlicensed ATf anyway?
Originally Posted By: PT1
Use DEXVI not Amsoil....cheaper and will do just fine and last just as long. 4-4qt drin fills gets you 80% new fluid 5-4 qt drain/fills gets you 87% new fluid. 6 gets you 91%. 7 gets you 94%. I do this on all my vehicles. Never a trans failure yet. BTW, I have a 2006 YukonXL 4L60e with DEXVI and it runs fine. WHen I do my home "flush" I drive a day between each drain fill to mix it up. Takes a week to complete. I use a fluid extractor because I have no drain bolt. Easy peasy. I did get one dealer flush...no difference in performance than by DIY.
Not sure I agree, Amsoil ATF out performs all other ATF tests that I have looked at. If you run your ATF 15K-20K it might not matter, run it 50K to 100K and it will matter.
Have you some tests you can point to that show DEXVI performs better than Amsoil ATF?
DexVI is the only ATF speced by GM for their transmissions. It is the backwards compatable ATF for all Dexron ATF's. GM has done all the testing. Amsoil is not licensed by GM for that application. Then add the fact that you can get it for 1/3 the price and GM specs it for 50k severe and 100k normal service in a 2006 4L60e what is the better value? So you can do three 30k OCI's for the same price as 1 Amsoil OCI. Sorry, I'm going with DEXVI. Why would anyone pay 3x for an unlicensed ATf anyway?
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It may be possible to get the vast majority out in just one. The first time I dropped the pan on my truck I welded in a 1/2" thick plate, drilled it, tapped it, and installed a drain plug. This doesn't help get any more fluid out but it sure made subsequent changes much less messy. I found that dropping the pan only removes about 6 quarts. I think the capacity is about 14 quarts for my truck so that's more than 33% right there.
My transmission has an access plug in the bottom of the bellhousing which allows access to the torque converter drain plug. Draining that thing took a while but I got around 5 or 6 quarts of of that. This didn't drain the lines or the coolers but I felt really good about getting that much out.
Ford stopped putting the drain plugs in the torque converters and I don't know about GM transmissions but it is definitely worth looking into. I've wondered about the feasibility of installing your own plug if not originally equipped.
My transmission has an access plug in the bottom of the bellhousing which allows access to the torque converter drain plug. Draining that thing took a while but I got around 5 or 6 quarts of of that. This didn't drain the lines or the coolers but I felt really good about getting that much out.
Ford stopped putting the drain plugs in the torque converters and I don't know about GM transmissions but it is definitely worth looking into. I've wondered about the feasibility of installing your own plug if not originally equipped.
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