Another Transmission Cooler Post

So I am going to go ahead and add a cooler to my new used '99 Windstar. It looks like the major parts stores are carrying the flex-a-lite, something like this:

http://www.amazon.com/gp/product/B00029J3W0/qid=1153139968/sr=1-12/ref=sr_1_12/102-6412847-3322557?%5Fencoding=UTF8&s=automotive&v=glance&n=15684181

I see that these seem to come with 3/8" connections, but the Windstar hoses are 5/16". Has anyone seen a cooler with the straight 5/16"? If not, how did you adapt it?

This looks real easy on the face of things. Clamp both hoses on the existing cooler (to cut flow), pull out the lower end hose on the existing cooler ("out") and run a hose from that cooler connection to the "in" connection on the new cooler, re-connect the other hose (leading back to tranny) to the "out" connector on the new cooler. All of these hoses are rubber (not metal) right?

I plan on blowing compressed air thru the existing cooler to make sure it is not clogged. Is there anything else to be done with it? Seems like there is a TSB advising multiple tranny failure could be due to clogged coolers. Anyone gotten any sludge out of blowing it? Seems pretty important as a new cooler would not be effective if the old one is clogged.

OK, looks like NAPA has a tranny cooler flush:
http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=BK&PartNumber=7652614&Description=Kooler+Kleen+A%2fTrans+Cooler+Flush

Ford has a procedure for flushing the cooler. This is not the same as a "tranny flush" ... which Ford is very much against.

The cooler is disconnected from the tranny and hooked to a flushing-cleaning machine.

If you have a radiator shop in your area, you might check to see if they would flush and clean your cooler if you were to remove it and take it in.

The stock cooler is removable on this vehicle?

I probably should have typed "coolers" ... plural.

The basic trans cooler is part of the radiator assembly (at least on my model, I believe) and the stock aux cooler is attached in front of the ac condensor.

Along these lines, is it possible to replace the stock AUX cooler with an aftermarket one, or are you better off adding the aftermarket in?

Z.

You CANNOT effectively "flush" an ATF cooler, if contaminated, they MUST BE REPLACED.

Why? Nearly all ATF coolers, and all air-to-ATF coolers that I know of, have "aluminum wool" inside to improve heat transfer, and you simply cannot flush any junk out of them. It is basically like having "Steel wool" inside a tube. Im agine stuffing a scowering pad into your sink's drain... how well would it trap "stuff"? Damned well, and no flushing would ever completely clean it.

It is also NOT a good idea to install coolers in "Series" (one after another) because each cooler will add flow restriction, reducing the total cooler flow - which when fed back to the transmission is the Lubricant for the "hard parts".

ModMech
You make a good point ... and the cost of coolers and radiators is not too much if one does some shopping.

I did not know about the internal metal mesh.

And Ford doesn't mention it (So what's new!) in the procedure "Transmission Fluid Cooler -- Backflushing and Cleaning", Page 301-01-328 of '99 Windstar Shop Manual (FCS-12249-99-1).

I guess my first question should have been: is there a known issue with coolers clogging in this vehicle? Because the fluid is being cooled, there is the possibility of precipitates collecting. I guess a visual inspection is easy enough, though not much would be visible. No sense in adding in a aux cooler if the main is clogged.

FORD's TSB's about cooler flushing when replacing the transmission are all about major transmission failure where major crud ends up in the coolers, both the radiator mounted cooler, and the auxillary cooler. They found that, following a transmission failure, that resulted in major crud in the fluid.......clogging the cooler(s), that the new transmission was failing in short order...... The cause was that the cooler(s) was clogged with crud, causing the new transmission to overheat.

I would NOT expect this to be an issue in normal, good transmission, maintenance.

Hey Wiswind, do you have any pitures of your aux cooler installation? I've seen how you've installed the in-line magnetic filter but did not see the cooler itself. I like your approach on protecting the tranny and the pictures you provide are exellent. thanks

I did not post pictures of how I installed it.....because I could not get good pictures.....due to the location of it.

Mine is installed in series with the in-radiator one........fluid flows from the transmission, through the factory in-radiator cooler, then through the auxillary cooler.

I mounted it onto the front of the condensor coils....which cover the whole front of the radiator (the fins that you look at behind the grill are actually the air conditioner condenor coils....and the radiator fins are behind that).

Mine is mounted toward the TOP of the radiator for 2 reasons........one...being that it was easier to mount......and second, it gets much less abuse in the form of stones hitting it......as noted by the smashed fins below the bumper versus the near perfect ones above the bumper.

I used the nylon straps that you push through the fins of the condensor coils and radiator, and then push a zip tie style "button" onto the other end that sticks out behind the fan.......then trim the extra stub.
I still had to loosen the dual fan assembly to reach down between the fans and the radiator fins.
The ABS unit needs to be loosened and moved slightly in order to completely remove the fan assembly.....and I was afraid to do that......due to flexing the steel lines.....

I used a Derale brand of cooler, which came with 3/8" fittings.....and I bought some brass adaptor fittings to install inline.....so I have a short section of 3/8" hose from each fitting on the cooler....which then goes to my adaptor fittings (bought at a hardware store) that adapt the line to 5/16", which is what the FORD lines are.

I have had this cooler in place for several years....and it has been fine.

I also found that there is real nice airflow through the cooler with the radiator fans running.......

I took some time to route the lines behind the driver's side headlight.......
I mounted the cooler with the fittings pointing UP and ran the hoses over through whatever holes I could find near the driver's side headlight....and ran them down on the engine side of the radiator support.....
I put short lengths of those rub strips that you put on the door edge......onto any sharp metal edges that were near the hoses....to prevent any possible rubbing.
I also put some of the plastic/nylon coverings that they sell for "engine compartment dress up" over the hoses where I thought that they might rub against anything......

As a side note.....which I have mentioned a few times elsewhere......
It would be well worth the time to check to see if the radiator fans operate on low speed.
With the engine at idle......and the A/C turned ON......the fans should be running.
If they are not......check the radiator fan low speed dropping resistor......
Mine was broken....most likely as long as I have owned my vehicle (1999 until last fall) and I tracked it down.....and replaced it.
I posted pictures of that in my pictures.
The point being, when you are stuck in traffic on those HOT days......those radiator fans running on low speed will make a MAJOR cooling impact for your transmission.....and engine.

Another side note......when I am going to travel with a light trailer (once a year), I remove the in-line Magnefine filter.....just to make sure that I get MAX fluid flow.