I have a 95 Explorer and the trans is due for a fluid and filter change. I have had a transmission shop that I trust NOT recommend a full flush and to only drop the pan and change the filter. However, my Dad said the dealership that he got his F150 from does the full back flushing and chemical cleaning.

What is the concensus on this issue...to flush or not to flush?

 

Did they give you a reason to that? I've been told that only 1/4 to 1/3 the total fluid is sitting in the pan, so it made sense for me to totally flush the trans.

 

i was told flushing was bad (only) if you don't know the previous mant. ......the reason was flushing the fluid removes the built up junk thus causing slippage......sounded good to me but i read this after i change fluid (aod) no adjust......i do have slipage but i'm not sure if it happend befor or after.....since first change i have change 4 times this year... hopefully no more slipage.....i used a OEM filter this time too hopefully it helps.........i am hopeing this is the prob because a new/rebuilt tranny is mucho $$$$$$$$$$$

 

We don't do the "flush" thing at my shop either. A "transmission flush" is nothing more than an expensive way to change the fluid. First, there is no "flush" or "back flush" function. All that the flush machine does in catch the fluid that the transmission's pump is pumping out to the transmission cooler and pump new transmission fluid it the return line from the cooler. The new fluid is dumped back into the pan as normal. There is no backflushing, cleaning, purging or anything else going on, it just pumps out old fluid and pumps in new fluid and the transmission works as normal throughout. Anybody tells you any different and either they don't know what they are talking about or they are feeding you a line of BS.

True that only about 1/3 of the transmissions total volume of fluid is in the pan. As an example a 4R70W (AODE) holds about 12 quarts total with about 4 in the pan. However, the E4OD and AODE both have drains on the torque converter so you can drain an additional 4 quarts or so from the converter too. That changes 2/3 the volume.

True you can change the entire volume of fluid using a flush machine but almost nobody runs the machines long enough to accomplish this. The salesmen that come to my shop to sell me these machines all tell me how much money I am going to make off the machines. They all tell me I can "sell" a "flush service" for twice what I get now and use the same 4 quarts of fluid plus I don't have to take the time to drop the pan or buy a new filter.

Its all marketing hype. If you change your fluid the old fashioned way (drop the pan) and do it regularly, you won't have any need to change the entire volume anyway. This is because regular service will keep the fluid from getting old and nasty.

Oh, and the "chemical cleanings" are just as bogus. ATF is full of detergents and makes an excellent solvent. For this reason many transmission shops use hot transmission fluid to flush the transmission coolers on vehicles in for overhauls.

Steve

 

So if you remove the pan, the plug on the converter, and the lines for the tranny cooler you should get most of it right (E4OD and AODE)?

I was also told that a flush is recommended if the fluid is burnt, and to use straight Mercon because Ford does not recommend using dual purpose fluid.

 

That should get most of it. There will still be a couple of quarts in the accumulators, servos, valve body, drums, etc...

If the fluid is burnt, it should not be changed at all. Realize that its not the fluid that is burnt, its the clutches and its burnt clutch material that turns the fluid brown/black and gives it that burnt odor. Changing the fluid will not fix the problem and in some cases can make it worse.

Dextron/Mercon works fine in fords. If its a late model Ford that specs Mercon 5 then you need to use Mercon 5.

Steve

 

Don't put back in one of those metal screen filters. There is a newer MicroFelt filter that can catch the gunk that will come out of the TC etc. Just ask for one for a 97 V6. These are about $23 locally or $10 at www.bulkpart.com As name implies, these are bulk and don't come with O rings and pan gasket. One caution, these require shorter bolt or aditional mounting hardware. Bolt will bottom out, filter will drop down and suck air. I did a couple pan droppings on my high mileage 97 Explorer before I did a pump flush. Had to change the filter each time which was loaded, a good reason to buy a couple at bulk. 40K later I'm running clean and no problems. Also added cooler and external spin on tranny filter.

 

So if you just drop the pan and you are only getting 1/3 or so of the fluid out and changed, what is the purpose? Is changing the filter the biggest reason for dropping the pan?

 

sofar my "flush" seems to have worked. before i had a bit of a slip or hesatation. i haven't seen that since last fluid change. i only took 3-4 changes to get these results but i am happy sofar....oh and what do you guys think about installing those drain pluges? yah or nah?

 

I didn't add a drain plug last time I dropped the pan, but next time I'm gonna. I used a large metal "pot" to catch the fluid, and it got most of it. But I'd rather take out one bolt than have to take off 16 blots, then use up that RTV sealant.

Changing 1/3 of the fluid will still help out, especially if you drop the pan regularly, after 3 or 4 times you will dilute the old fluid enough that it will be mostly new, to my understanding. But since I'm under there, I'd drain the torque converter and cooler as well. I change the filter at 90K, and it was still clean. But the fluid was nice and black. At the dealer I payed something like $65 for it, but I don't thnk it's needed every draining. I just had my trans rebuilt, and since I'm always hauling and plowing, I'm gonna change the fluid at least 2 times a year. I can't afford another rebuild.

 

i just put one in mine $7 and no more headache
just drill a little hole in pan clean pan and insert plug then tighten so far no leak and i am looking forward to the next change (seeing how it will only take about 5 min)

Cooler? where is that?

 

Here is the best idea. www.yourcovers.com has finally made a cast aluminum pan for the A4LD, 4R5E5, 5R55E. Well almost, they have a pan now that is too short for the 4WD filter. New deeper pan will be available in Feb. This has a drain plug and a place to put a temp sender (extra cost). Pan adds an extra two quarts to the system. If you have a remote filter, you can spin it off, just pump out a little and this is less of a mess when you drop the pan. I have used the same gasket multiple times without a problem, but always have a spare. I like multiple drops because changing all the fluid does not get all the dirt out. Always throw in about 5 extra magnets. They will get covered.

 

you put magnets in your tranny pan?

 

Just stick the magnets inside the pan. My experience with the A4LD and 5R55E is that these are dirty nasty transmissions. They are always producing sediment. I dropped the pan on my 89 Cherokee @ 135K and it was spotless and no one ever said they made great transmissions. My Fords have always turned a rag black. If anyone has found their pan clean, I'd like to hear about it.

 

I recently changed the tranny fluid in my '00 Expedition with a 4r100A transmission. The fluid was cherry red and showed no signs of sediment or contamination whatsoever suspended in the fluid. It only had 30k miles on it though. The pan has a factory installed magnet. It is a small donut shaped magnet that sits in the bottom of the pan. This was the only place that there was sediment, around the magnet. There also was the typical fuzzy metal shavings on the magnet that I expected to see on the first fluid change. That stuff won't come out with a flush. I spent quite a bit of time with lint-free rags cleaning the pan and magnet.

I drained the cooling lines, the converter, and then dropped the pan (no plug on 2wd with this tranny). I was actually able to evacuate the entire fluid capacity, within a quart. The only thing I found strange was that the plastic plug from the factory was missing.