I have a 93 Bronco, about 270,000 miles on it, 302 with a E4OD tranny. I got the Bronco with 204K on it and had the tranny fluid (black at the time) flushed, pan dropped and filter replaced, and added 1 qt of Lucas Transmission addative. Again around 240K I was in need of another fluid change, however, the original shop that i took it to before no longer would drop the pan and change the filter!! So i took it somewhere else, but I was never happy with how clean the fluid was after repeated flushings by them. Now I am going to be doing it again, except I will be doing it myself following the procedures in the following tech article:
https://www.ford-trucks.com/article/...nsmission.html

My concern is that after draining the torque converter and starting the engine, will this cause damage to it being that there will be no oil in it for a short time? Also, should it be started and idled in Park or Neutral? I have had problems with torque converter shudder/chadder/lockup as the oil gets dirty. It also has a burnt smell and after 45 min or longer drives at speed over 55 mph, the smell of burnt tranny oil can be smelled when stopping the vehicle. Therefore i think i am having a problem with the cooling of the fluid. Could my oil cooler be plugged or restricting flow? If so, what type of cleaner/solvents could I run through it? I would most likely disconnect both lines and force a solvent through with a air compressor. Does anyone know the operating pressure from the oil pump so I don't burst any lines with the compressed air?

Another question I have is what oil should I use? I am debating between using Motorcraft Mercon (NOT MERC. 5!!) oil, Mobil-1 Synthetic ATF, or probably a Castrol Mercon or similar oil. I will also be adding a quart, possibly 2 or the Lucas Tranny addative, however, this will be done once a majority of the oil has been replaced since it is so thick.

Basically when I originally changed the oil at 204K I was told that I will be needing a torque converter soon due to all the metal filings in the tranny, yet here it is 70,000 miles later and still running strong (No major slip). I am looking for a procedure to remove ALL the old oil and clean out my cooler, and replace all that with a good quality Mercon Oil and new filter/gasket. I am trying to stretch the lifetime of the tranny and if any of the mention steps will harm it please let me know. Also, while the oil pan is off I will also be spraying it up with some Ford Blue Engine Enamel, just for looks of course. And one more thing, should I use a small bead of RTV gasket maker with the gasket or just the gasket?

Sorry for the long post...Any input is greatly appreciated. Thanks in advance...

 

No, that won't be a problem. Just be sure to fill the pan before starting the engine. Keep it in park. It's safer, and the fluid flow is exactly the same as in nuetral. Also make sure at least one time to move the shifter to each position while the fluid is pumping out. That will change fluid in all the clutches, servos, accumulators, etc.

It is possible that it is restricting the flow. You can test it while doing the flush. Get a second container for the old oil. While the engine is running, move the oil flow to the second container for exactly 15 seconds. You need to have at least one quart in the second container. If there is less either the cooler is plugged or the pump is dying. I don't know of a good way to clean out a cooler. I recommed replacing a plugged cooler, not flushing it.

Any of those are fine. I use the Mobil 1.
If you have the original rubber gasket reuse it without any RTV. It's the best seal you'll get, and the gasket is designed to be reused.

 

You say to keep it in park, its safer, yet I should cycle through the grears to purge out all the old oil. Am I correct to assume once oil flows out of the return line from the cooler that it is safe to shift through the gears? Anyone know the flow rate of a good pump? Just wondering how quick I'll have to be replacing the fluid as my girlfriend shifts through the gears a few times.

I am just a bit skeptical at this method since the transmission is so old (very high mileage) and it will be running a short time with no fluid. Would it be worth it to remove the extra quart or two via the cooler return line?

Also, I have never run synthetic and I am worried that it may cause more harm than good. I have found just as many posts here stating it will do harm as well as good to a old tranny. This is probably not recommended, but what about 50% Mobil 1 and 50% Motocraft or other non-synthetic Mercon along with the Mobil 1.

Any benifit to just using Motocraft Mercon vs. any other leading brand of Mercon? I have read here that Ford is only required to disclose certain ingrediants in their original oil, and therefore it will contain certain agents which the other's won't, and would be better since it was designed for this transmission. Yet on the other hand, the E4OD has been around for several years and so has Mercon oil, therefore most of the oils are probably all similar at this time.

I know the original gasket is long gone, and more than likely has a cork one, which will get replaced. I asked about the RTV since i have heard the silicon and oil don't mix, yet it is standard on many dodge applications which don't use gaskets!!

 

I get nervous with RTV in an application like a trans. What happens if a blob separates from the seal area and floats around in the pan. The filter should catch it, hopefully. If you are not leaking now, a quality gasket should not leak when you put it back together. Don't over tighten the bolts, just give them the torque they call for in the book.

 

I just did my girlfriend's tranny on a truck she just got which was leaking since it was missing a bolt and had 3 already stripped. I redrilled and tapped with the next size bolt after dropping the pan and replaceing both filters and gasket (2000 dodge dakota). There was no gasket on it, and ALOT of silicone. This is why I ask, because I put on a new gasket, and a sliver of RTV top and bottom of the gasket, bolted and torqued it, then it sat overnight before putting in the oil.

I have read on this site that ford advises not to use silicon on oil pans, yet dodge does it like that from the factory, and they don't even use gaskets. There are no gaskets on any of the oil pans and differentials on my girlfriend's dodge, and it looks the previous owner had all the service done at the dealer. I too didn't like the idea of having silicon get into the oil pan, so I always favor the outside edge when applying it.

 

A truck driving girlfriend! You're doin OK.