Just wanted to share my experience flushing and replacing the automatic transmission fluid in my 2001 EB expedition with 4x4 and the 4R100 transmission. The Expy has 97,100 miles and this is the first time the transmission had a complete flush. I’ve changed the transmission fluid and filter twice before performing this procedure today, so the fluid was dirty but not black and it smelled like regular transmission fluid; no burnt smell.

Preparation:

To get the transmission ready for the flush, I drove about 20 miles had breakfast and a coffee and returned home and placed the truck on jack stands (4).

System Flush:

I followed Mark Kovalsky’s guidance step by step here:Changing ATF Fluid in a E4OD and 4R100 transmission .: Articles Thanks Mark. Another satisfied DIYer.


You can do the job without a helper. You just need to get a hose that is 10’ long that way you can extend it from the transmission line to the bucket where you can observe the flow from the driver’s side of the truck. I think this is best that way “you” can see the air bubbles and not rely on someone else’s vision of air bubbles. It only took 2 engine run cycles to flush the system. The 1st cycle pumped out 2 gallons (8 quarts), which is when bubbles started to form and the second cycle pumped out the rest. I guess it’s best to perform this procedure in the summer since the ambient temperature will keep the transmission fluid hot for a longer period of time.

I changed the filter because I wanted a totally clean slate since this was the 1st complete system flush; the old filter was dirty too. Personally, I recommend changing the filter if this is the 1st ever complete system flush. I did not drain the torque converter because, as Mark stated, the fluids will be pumped out during the engine run step. The next time though I probably will just do the flush and leave the filter in place. No cleaners were used during the flush.

Note: The transmission return line that goes to the back of the transmission measures at 3/8”, however, there’s a flare at the end of the line that is 1/2" so you will need to get a 1/2" ID tube to fit over the flare end and a clamp to secure the hose. The nut to remove the transmission line requires a 5/8” wrench.

Fluid quantity:

I purchased 18 quarts of Mobile 1 but ended up getting additional quarts because I used a few extra quarts to ensure the entire system was flush and without air bubbles – basically, I used the extra quarts to push the air out the system on the 2nd (last) engine run step until the air pocket were gone. Besides, you can return any unused quarts.

The 4R100 takes the deep pan transmission filter – at least mine did. Also, the transmission holds about 17 quarts and the pan holds about 9 quarts; I measured the quantity at each step for future reference.


Al

 

Wouldn't it make more sense to disconnect the return line at the transmission? That way you would flush the trans cooler in the radiator. This would seem to be a critical step to me, or did I misunderstand the procedure? This should also allow a much shorter piece of clear tubing if I am not mistaken.

 

That seems like a lot of work. Did you use a better quality fluid? Is there a reason you didn't take it to a shop for this?

There is a shop close to me that charges $99 to flush the transmission.

They have a machine that they connect in line with the fluid. They circulate the fluid then pump in new fluid. They use 1.5-2 times the fluid need to fill, this makes sure that it is flushed well.

Only draw back here is you have to use the fluid they use. You couldn't replace with better fluid or synthetic, etc.

I've had them do all of my cars over the years with no issues. Plus they are so much cheaper. The other places I know that do this charge $150+.

 

I believe that's where he disconnected the line.

I used this method and used the MLM synthetic transmission fluid. It cured the slight shudder I was experiencing when pulling the trailer when the Torque converter locked up.

The only thing I did different, since my '02 Navi has the drain plug in the pan, the Ford Service manual says not to change the filter (unless the tranny requires an overhaul), so I didn't. I *think* the theory is that by dropping the tranny pan drain plug that actually back flushes the filter. But I did drop the pan for an inspection and cleaned any sediment out.

Tranny fluid is now a bright cherry red!

 

I did connect the clear tube to the line at the back of the transmission.

Alot of work for some yeah, but for me...nah. I used Mobile 1 synthetic, plus I know it was done and with the transmission fluid I wanted. I read a thread here where the guy paid for flush and filter change (external kind) but the mechanic forgot to change the filter; guess he figured the owner would never know, but he checked and the filter was not changed. I just don't trust folks working on my vehicles, especially when I know I can do the same job with better quality parts - cheaper.



At $99 dollars maybe I would let them do it, as long as it's a complete flush and not just draining the pan. Here the dealer wants $200 plus tax for the standard Mercon for a power flush, one local shop wants $270 plus tax for synthetic, and one shop wants $125 plus tax just to drain the pan, replace filter and fluid. The $99 sounds like a good deal. What type of fluid do they use?

 

There's a local shop that dos a tranny flush and sometimes runs a $99 special. They say the fluid is compatible to mercon but it isn't actually mercon. Still puzzled over that one.

I just go to the dealer and pay $150.00 plus tax. Then it's in Ford's records.

 

Hi All,
Thanks Methodical for making this post- your information, along with the artical from Mark made this quit easy.

I'm lucky enough to have access to the Heavy Repair Shop at my office, so it was VERY nice to drove over the pit and be able to work standing up.

Following the directions, I was a little intimidated, but with many wrenching hours behind me everything made sence. One of my mechanics tried to talk me out of this proceedure suggesting that running the engine was dangerous without adequate fluid in the tranny. He insisted that if I wanted to continue anyways that I watch for the cavitation very closely and stop the engine as soon as I see any evidence of bubbles coming from inside the trans.

After draining & removing the pan, I changed the filter. On the top of the filter inlet tube (the part that stick into the trans) there's a small orange rubber o-ring that stuck in the trans when the filter came out. Since the trans was still quite warm it was a bit of a job to get it out but my mechanic insisted that I wasn't to use any tool but my finger. (with a rag around it if it was too warm for my pensil pushing fingers - I'm a salesman ) it came out after a minute or two.

I reinstalled the pan and tightened then torqued each pan bolt evenly.

One advantage of draining the hot ATF direcly into the collection barrel was that I didn't loose the drain plug in the fluid, and was a "fairly clean" proceedure. The down side was that I really had no idea how many quarts (litres) of fluid had been drained. My mechanic suggested that my initial fill should consist of about 10 quarts and he was right on.

I tried twice trying to run the engine and watch the tube by my self, but I kept hearing the return / disposal tube leaking and didn't trust where I was going to see the bubbles from. I got the assistance from my mechanic to start and stop the engine while I attended to the connection below. It was very hard getting a good seal but a much better seal when I was able to hold the connection straight.

The first evidence of cavitation was a what I would consider to be a "very large" bubble in the line. It was very easy to see.

I then filled 7 more quarts, and started to flush again.

The second part of the flush, I had my mechanic shift into drive & reverse to help flush out those chanels. The second portion of the flush took what felt to be approximatly the same amout of engine idle time for the fluid to change colour, as it did the first time to produce the cavitation. I was worried that I was going to miss it but it was very easy to identify when the change happened. However, once all of the fluid in the tube that I could see changed to the brigher red of the new fluid, I began to second guessing my self, thinking I was worried about flushing out too much fluid, and running out of ATF. Since my mechanic did stop the engine as soon as I recognized the colour change right at the beginning of the tube, the flow of the fluid stopped before the end of the 10' hose, and I could see "the line" between the old fluid and the new.

After the flush was complete, I reconnected the return line and cleaned off the underside.

Restarted the engine and let it run for a few minutes watching for leaks. Upon checking the fluid level I needed to add 1 more quart.

Excluding a 1/2 hour worth of clean up, I took 2 hours to complete using only hand tools and waiting for a few minutes for assistance. (The trany shop quoted me 1.5 hrs).
I was slow and diligent with everything and didn't get frustrated, mainly becuase I didn't have any time constraints and nothing went wrong. It was very easy and straight forward and I used exactly 18 quarts, as was stated in the instructions above.

On the drive home - the rumble when shifting under load was gone !!!!
In addition, when testing on the ride home, my Expy appeared to rev higher before shifting, as opposed to where I was expecting it to shift. Smooth shifts and no rumble !!!

Thanks guys!

 

That is why it's so cheap. And that is why I don't like others to work on my vehicles. I can do the same or a better job with better quality parts or material.

Spinner, glad it worked out for you. I only wish I could work standing up - makes working on vehicles that much easier.

My shifting is much smoother too - definitely better than before. Funny I've never had the filter seal stick on me - changed 3 times. You shouldn't have the problem again since you put a new one in and there should be fluid on it after the change.

 

That's why you always take the time to ask all the right questions. Price alone should never be a consideration to have any piece of work done to anything you own.

Likewise, the dealer will always be higher. They seem to have an arrogance about them that justifies the higher price for parts and labor.

 

Can you explain what you mean by 2 engine run cycles?

 

He briefly ran the engine with the cooling line disconnected. This was so the pump would pump the tranny (almost) dry. After turning the engine off and refilled the tranny and did the same thing again. This would've flushed out virtually all of the old fluid.

 

Thanks Alloro, Yes. you're exacly right.

 

Sorry for the lateness Spinner_89 Alloro is correct about the 2 engine run cycle.