Transmission Service

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But why put yourself through the mess and anguish of a cooler line drain when Jatcos have an easily accessable drain plug and a dipstick tube to fill from? They're easier than an engine oil change.

Joel
 
Originally Posted By: tig1
Correct me if I'm wrong, but I have heard that if a transmission filter gets clogged it becomes harder for the pump to push fluid through the transmission and pre mature pump failure can occur. Any truth to this?


Depends on which trans and which filter. On GM transmissions with a replaceable filter the filter usually gets fairly filled with debris on the initial 20k with break-in debris. Once changed it takes a long time for it to accumulate that much again. If not changed it will hamper the pump performance over time. I have hed 2 GM trucks where the trans pumps started making noise (whooshing sound) and once the filter was changed it stopped. In both cases the factory filter was run past 80k.
 
Originally Posted By: JTK
But why put yourself through the mess and anguish of a cooler line drain when Jatcos have an easily accessable drain plug and a dipstick tube to fill from? They're easier than an engine oil change.

Joel


Cooler line flushes are easy. Once you do one you will stop doing drain fills.
 
They are easy on some cars... I guarantee you don't want to do it on my Santa Fe. You would have to remove the bumper to get at the cooler lines, or you could take out the battery, air box and lower radiator hose to get at the Banjo connectors on the transmission that feed the cooler.

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I'm not a fan of doing partial fluid changes. I'll bet some of the same people who insist on gettng every drop of dirty motor oil out of their engine are the same ones that do only partial transmission fluid changes. The drain plug is there to make the pan drop easier without the "red bath".
 
Originally Posted By: JTK
But why put yourself through the mess and anguish of a cooler line drain when Jatcos have an easily accessable drain plug and a dipstick tube to fill from? They're easier than an engine oil change.

Joel


A lot of fluid sometimes most of the fluid is not in the pan but in the converter and in places that don't drain back into the pan,e.g. my Expedition holds almost 20qts with 6qts in the pan only.Doing a drain and fill is like doing a 2qt oil change on a 5qt system.A line off fluid exchange(it is not a flush)gets all the fluid except what small amount may be left in the line.

While the drain and fill method maybe easy it really only benefits the owner with a feel good factor,the transmission got a percent of new fluid that just got contaminated with old fluid,not really enough to make a difference.
 
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Originally Posted By: Kestas
I'm not a fan of doing partial fluid changes. I'll bet some of the same people who insist on gettng every drop of dirty motor oil out of their engine are the same ones that do only partial transmission fluid changes. The drain plug is there to make the pan drop easier without the "red bath".
If you stay on top of your fluids there is nothing wrong with doing it this way. I have driven original transmissions to well over 400K KM (240K miles) without issue so I'm sure my method works fine.

In my manual the "Plug" is for servicing the transmission fluid and removing the pan is "forbidden" unless there is a problem that needs to be fixed.

The filter/screen is "lifetime"
 
Originally Posted By: PT1
Originally Posted By: JTK
But why put yourself through the mess and anguish of a cooler line drain when Jatcos have an easily accessable drain plug and a dipstick tube to fill from? They're easier than an engine oil change.

Joel


Cooler line flushes are easy. Once you do one you will stop doing drain fills.


Try to do this on a used vehicle with rusted lines and fittings, and not being a repair shop with all the specialized tools and ability for the parts stores to deliver parts that break unforseen.

Ending thought, listen to stevieC, always sounds he knows whereof he speaks.
 
Thanks JC for the compliment... I just try to share the knowledge and experiences I have had in the past. I have seen many things and been fortunate enough to have a mechanic as a father who is very smart (IMO) teach me tips, tricks, and proper ways to do things etc.

I might be 27, but I have driven countless miles because of the job I have and have rebuilt engines/transmissions with my dad at the age of 12 on so I would think I have seen a lot and learned a great deal.
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I was the kid learning while the others were playing hockey or video games... I thought it was fun, and now I see how valuable my fun was.
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Originally Posted By: jcwit
Originally Posted By: PT1
Originally Posted By: JTK
But why put yourself through the mess and anguish of a cooler line drain when Jatcos have an easily accessable drain plug and a dipstick tube to fill from? They're easier than an engine oil change.

Joel


Cooler line flushes are easy. Once you do one you will stop doing drain fills.


Try to do this on a used vehicle with rusted lines and fittings, and not being a repair shop with all the specialized tools and ability for the parts stores to deliver parts that break unforseen.

Ending thought, listen to stevieC, always sounds he knows whereof he speaks.


There are two trains of thought going on. One is changing the fluid out on a unit that may not have been serviced and the other is maintaining good fluid by changing a portion out at regular intervals.

Both have merits, but when a unit has a unknown service history or its known that the fluid has seen long service it is best to change as much of it as possible.

Many Asian and some domestic cars are fitted with rubber hose OEM making it easy to do a line off. As for rusted lines and fittings with no access to tools or parts then any job can be a potential disaster, most folks here seem to know their own limitations. Common sense should dictate when a potential problem looms, a rusted part or something that requires special tools that they should expect the worst and be prepared to deal with it. Leave it until the parts or tools are available, worst case take it to a mechanic.

IMO generally speaking the line off method is preferable to the alternatives others have offered, of course there are exceptions. Every car is different as is the ability of the individual performing the work and the vehicles maintenance history.
 
Originally Posted By: StevieC
If you stay on top of your fluids there is nothing wrong with doing it this way. I have driven original transmissions to well over 400K KM (240K miles) without issue so I'm sure my method works fine.

Stevie, I'll have to take your advice with a grain of salt. I know you drive roughly 60K per year. I can only imagine that this is mostly highway driving where very little shifting is going on. Your advice may not be realistic for people who run only 10K per year on their vehicles and run a lot of shifts through their transmissions.
 
There was at one time here a listing on how many times to do a drain and fill to end up with a complete fluid change, "at least for all pratical purposes". It took into accounthow many qts the transmission held, and how much was drained out.

Example: Capacity 8 qts, drain 4 qts= 50%
drain another 4 qts = 75% and so on.

I just bought a used 2001 Escort and had the so called filter replaced, and had an adapter welded onto the pan so I could do a drain and fill periodically. Reason being, to remove the pan the transmission needs to be jacked up for the pan to clear a cross member.

I normally do a drain and fill every 3 to 4 oil change, with oil changes every 5,000 miles. I also follow this same sch. for our newer car which we bought new.

Fluid whether engine oil or transmission fluid is very cheap compared to metal parts.
 
I pulled the pan off my Sentra at 100,000 miles and it was so clean you could have eaten off of it. It has a screen filter which won't come out because theres a bolt behind the valve body holding it.
The cleanliness was no surprise because it had seen regular Mobil 1 ATF drain and fills.
 
Originally Posted By: Kestas
Originally Posted By: StevieC
If you stay on top of your fluids there is nothing wrong with doing it this way. I have driven original transmissions to well over 400K KM (240K miles) without issue so I'm sure my method works fine.

Stevie, I'll have to take your advice with a grain of salt. I know you drive roughly 60K per year. I can only imagine that this is mostly highway driving where very little shifting is going on. Your advice may not be realistic for people who run only 10K per year on their vehicles and run a lot of shifts through their transmissions.
Kestas, we have those type of drivers in the family and as customers/friends of my dad and my advice still holds true for them.
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Originally Posted By: PT1
Originally Posted By: JTK
But why put yourself through the mess and anguish of a cooler line drain when Jatcos have an easily accessable drain plug and a dipstick tube to fill from? They're easier than an engine oil change.

Joel


Cooler line flushes are easy. Once you do one you will stop doing drain fills.


I've done 5-6 cooler line "flushes" over the years. It is without a doubt more hassle and more of a mess than drain plug drain/fills. I'll stick to the drain plug every time if so equipped. I know we all go round'n round about this topic from time time. I fully understand that you'll 'transfuse' ATF more effectively adding new ATF as you allow the AT pump to purge the old out a cooler line, but you are still intermixing new/old fluid even with a transfusion. New ATF dumps directly to the pan/sump and mixes with the old stuff before it's pumped out a cooler line. The other concept that we're all loosing sight of; This is in regards to a Jatco AT. I've never known a Jatco unit to be rough on ATF in the first place, they don't spec a pan drop or filter change ever and are the easiest to drain/fill trans I've ever touched.

Joel
 
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Originally Posted By: jcwit
Wish someone could dig up that chart I mentioned a few posts ago. I tried the search and got nothing.


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Here is what I do and have been very successful doing it. I can draw out ~2 qts of fluid with a small pump via the dipstick/fill tube. What I do is have a mechanic drop the pan, clean it, swap out the filter and refill the unit. Reason being if there were leaks it is his problem, and the job was never fun on my back.

After the mechanic did his thing I would drive home, and pump out ~2 qts of ATF via the dipstick, drive a little and do it again for a total of about 10 qts of fluid. I've been doing this every 25,000-30,000 miles and everything seems fine. I have done line flushes, but for people who have a hard time getting a line off or are afraid this method works well if they have a dipstick/fill tube.

The fluid is always clean and there is hardly anything to clean when he drops the pan. I could probably just swap out the fluid every 25,000-30,000 miles and do the pan drop very 50,000-60,000 miles but I'd rather be safe than sorry. The key is to never let the fluid get to the point where it is bad and really loaded with junk. This method works well for original owners of their vehicles, or people who know the transmission service history. The above can be modified for cars with unknown history.
 
Originally Posted By: demarpaint
I can draw out ~2 qts of fluid with a small pump via the dipstick/fill tube.



any advice on where to get a pump like that?

do you feed a hard tube down the dipstick tube? mike
 
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