Tranny fluid/filter change

[busboy4]

Just sharing something I learned today while changing the fluid/filter on my '96. I had done this once before but the memory was cloudy.
When I pulled the old filter, the rubber seal stayed in the journal of the tranny. As illustrated in my manual I used a screwdriver to gently pry on it, and it proceeded to come apart. Thinking it was only a rubber part I carefully removed each little bit of it. This took some time.
Then the new filter would not fit. Was it the wrong one? Did I screw something up. Several hours later I realized that the old seal was still there. It is actually a metal sleeve covered on all sides by rubber. I had only scraped the rubber off of the inner portion of it. I gently used a screwdriver to put light pressure on the top edge of it and slowly it slipped out.
Now I know most of you would not make such a sophomoric mistake but just in case I thought I'd let y'all know of mine.

[irish30]

A trick that I have to remove the filter seal is a 6 inch 3/8 drive extention. Use the end the socket would go on to pop the seal out. It is long enough to pry with but doesn't cut into the seal or the aluminum on the trans filter hole.

[lewisnc100]

My trick on my 2000 is using snap-ring pliers. Put them inside the seal and squeeze the handles, this extends the pliers against the inside of the seal and you can gently rock it out. Very easy.

[ModMech]

My trick is to NEVER drop the pan. As a professional mechanic, it is my considered opinion that changing the AT filter is an utter waste of time and resources. Why? If there is anywhere enough "junk" in the pan or fluid to cause the filter to become extremely dirty (clogged) to the point where it really does *need* to be changed, so much damage has already been done (that's where that junk came from in the first place), that changing the filter is a waste of money and time because the unit is doomed anyway. The second reason is difficulty. It is FAR FAR more important to change the FLUID often (20,000-30,000 miles) than it is to change the filter. What kills (mechanically) an AT? Two things, 1) HEAT, and 2) Burned ATF. The heat itself damages seals and causes internal parts to expand more than they *should*, which causes interfearances. Burned ATF causes loss of "grip", so it begins to slip, causing even more heat. This affects everything from nternal seals, bearings, and electrical components.

Changing the ATF on these vans takes about 30 minutes, and you really don't even get dirty. Changing the filter, will double that time, and make a BIG mess, without any real benefit. Is changing the filter "better" than not, I don't think it is. Filters filter BETTER as they get older, so I leave them in.

[busboy4]

I can't argue with your opinion. I am not a professional mechanic. I simply know that in 113000 miles I have changed the filter at around 45000 and 113000, fully changed the fluid twice and have never had a slip, clunk, hard shift or any other problem. Yes, the pan drop is a big mess.

How is the filter better older? Would you say an oil filter is also better older? Change it every third change?

[rodeo02]

Originally Posted by busboy4

How is the filter better older? Would you say an oil filter is also better older? Change it every third change?

A filter with *some* dirt/particles already stuck on it will be able to trap & hold smaller & smaller particles easier. Not the best situation for a full flow setup like a tranny filter, but that's the basic principle. I have yet to ever pull a tranny filter that is loaded with crud, & like ModMech says, if the filter was plugged, the tranny would be toast before you got the pan off anyway. You probably noticed on your 45K mile pan drop that there was some crud in the pan, but the filter looked OK. I am also not an advocate of regular pan drops. I do partial swaps by pumping/draining out the old & adding new ATF atleast once a year on my vehicles. A pan drop & cleaning atleast once in a tranny's life is not a bad idea to get an overall idea of it's condition- or to replace a leaky pan gasket! .
G/luck
Joel

[busboy4]

Hi Joel
I think we have talked about this before. I too like the fluid change routine where we replace all the fluid. You are right about the crud. At 45000 the pan and magnet had quite a bit of shavings where this time there were very few by comparison. I have dropped the pan for the last time. If I have the van long enough I'll do another pump out/fill in a year or so.
Thanks

[lewisnc100]

Yep, have to agree that changing the A/T filter really isn't going to have an affect on longevity. I dropped the pan on both my Windstar and my Nissan at the same time mainly out of curiousity to see their condition, was surprised that my Nissan with over 100k had less shavings than my Windstar with 45k, but still both were minor. I also wanted to take the pan off to install a drain plug so I can drain and add fluid easily, although it's only 50% of the total I do this often.

Actually I don't know of a single auto manufacturer that recommends changing the A/T filter ever in their service schedules. Yes some dealers recommend it as part of their "improved" service, but you usually won't find it in any service schedule.

I was actually at a Nissan dealership one time where the parts dept. refused to sell a guy an AT filter saying it was only a screen even though their service literature bragged about how they changed it when other dealer service depts. did not.

[ModMech]

That's right about the screen.

Most all A/T "filters" are screens more than a media type filter (air filter for example).

When you turn off your engine, much of the ATF in the body of the trans drains back into the pan, thru the "filter". When this happens, it pretty much back-flushes the filter. Any particles settle to the bottom of the pan, the metallics (typically the larger particles anyway) stick to the magnet, and cannot recontaminate the filter.

If you could KNOW the replacements absolute flow (new and clean) and it's "dirty flow" when it's filtering particles at 5 microns, then you could make a good determination about wether to change or not. I can tell you that the factory filters will flow over 100% of the transmisisons "need" even when VERY dirty, and some aftermarket ones cannot ever reach 100% of need, yes even new. They are just to restrictive when wet.