Our “New to Us” Mirada had 55,000 miles on it when we bought it and no service records, so we went through it and brought all the preventative maintenance items up to current schedule. One of these items was the Transmission flushing and changing of fluid.
I had performed a “Drain Fill” method of flushing automatic transmissions on my other vehicles and searched the internet to see if there was a similar procedure for the Ford F53, 4R100 transmission. I found the procedure and started gathering the stuff I’d need.
Basically, the transmission pumps fluid through the transmission, valves, clutches, cylinders, etc, the torque converter, then that last item in the path is the transmission cooler, when the fluid comes out of the oil cooler, its dumped back into the pan where the cycle starts all over again.
The “Drain-Fill” method takes advantage of this. When the fluid leaves the cooler, instead of dumping it back into the pan, we dump it into a bucket and measure it. We then add the same amount of brand new fluid to the pan, where its pumped through the tranny, and pushed the old fluid out.
I bought 5 gallons of Valvoline Maxlife Full Synthetic ATF fluid. This is comparable with the 4R100 transmission.
CAREFUL – Valvoline oil comes in the same container and the label looks identical.
Walmart seems to have the best price ($19 a gallon) so look around.
On some of the transmissions, the torque converter has a drain plug. Mine didn’t, so I proceeded with the Drain-Fill method.
Make sure the transmission is up to operating temperature before starting.
Below is from CHP on TikiWiki forum site. CLICK HERE to goto that site
1: Getting Started
- The transmission system holds almost 18 quarts of ATF, and you must waste a couple of quarts to be sure you get it all purged and replaced, so buy 20 quarts of MERCON ATF (do NOT buy MERCON V!).Ford also warns against using a fluid that has a dual MERCON and MERCON V rating. You may use either conventional or synthetic, as long as it meets the above requirements.
- A 10 foot length of clear tubing and one hose clamp, sized to fit over your cooler hose. There have been different size cooler lines over the years, so check before buying!
- If you don’t already have a special funnel that fits into the transmission dipstick tube, then you will need one of those, too.
2: Drain the pan, then replace and tighten the drain plug.
3: Pour 7 quarts of new ATF into the filler (dipstick) tube.
4: Disconnect the transmission-fluid return line at the transmission – from where the ATF returns to the transmission from the cooler.
This is the line towards the rear of the transmission. Clamp the clear tubing over the line that you removed from the transmission. This is where the old ATF from the torque convertor and coolers will come out.
5: This is where the second person comes in handy. One person starts the engine, while the other holds the line over the drain bucket.
A clothes pin can replace the person holding the line in the bucket.
- a: Run the engine until you see some air in the clear tubing. As soon as you see air shut off the engine.
- b: While the engine is running in step 5a above, move the shifter through each position from P to 1, pausing about 5 seconds at each position. This will change some fluid that would otherwise be trapped in the valve body, accumulators, and clutches.
- c: Refill through the dipstick tube with 6 quarts of new ATF. (That’s 13 quarts total so far).
6: Repeat step 5a thru 5c (That’s 19 quarts total so far).
7: Remove the clear line and reconnect the cooler line to the transmission.
8: Check the fluid level and use the last quart of ATF to top off.
9: Properly dispose of the used transmission fluid.
The above process should change about 95% of your old fluid. Now would be an excellent time to switch to Mobil 1 Synthetic, and install a Magnafine inline transmission filter.