94-97 T-Bird Transmission and Torque Converter Problems

If you’re like many of us with a 94-97 T-Bird and modular V-8 you have experienced transmission and torque converter problems when your car was at a fairly low mileage. A way to hopefully avoid costly repairs is to flush out your transmission fluid about every 30,000 miles which is generally the recommendation in newer Ford service manuals. This is a good way to prevent torque converter shudder which we know will kick in with these T-Birds around 50,000 miles or sooner. I’ve always felt that Ford was extremely negligent to never order a recall on these cars to repair them. Personally my torque converter died at 41,000 miles. Something that is generally unheard of. In most cases flushing the transmission fluid and changing the filter is a cheap afternoon job which in the long run could save you hundreds or thousands of dollars. It is interesting that many of us diligently change our oil every five thousand miles or sooner but don’t even think about our transmission fluid until the odometer has hit 100,000 miles or our fluid is the color of driveway sealant. In 1998 Ford began using an improved ATF called MERCON® V in its transmissions. MERCON® V fluid is now used in the 4R70W transmission and AX4S and AX4N transaxles. The fluid can be bought at your local Ford dealership and some auto parts stores. A complete flush with this new fluid and a bottle of Prolong is not a bad idea for those of you still running your original fluid. Bear in mind that torque converter failure is only a problem with 94-97 Birds and in most cases does not apply to the highly reliable transmission that were mated up to the 302’s of yesteryear.

Ford TSB 98-3-6 recommends MERCON® V for AODE-4R70W transmissions to cure Torque Converter shudder. I know that the late nineties Crown Victoria’s and Marquis use this transmission with better results. This is basically the same transmission in 1994 and up Thunderbirds so if you ever need to replace your entire transmission one from a salvage yard is nearly always cheaper than a re-build. A wrecked low mileage police car is usually a good donor.

One of the more popular and widely accepted additives is made by a company called Lubegard. They make a 4 oz. additive under the trade name “Dr. Tranny’s Instant Shudder Fixx”. Most Transmission repair shops will have this. I have also used Prolong and Slick 50 in my transmissions and believe this helps the oil’s viscosity.

The 94-97 T-Birds are equipped with the 4R70W transmission that has since been improved and updated by Ford. This transmission has the failure-prone roller type one-way clutch that Ford eliminated in ‘98 for a much better designed mechanical diode one-way clutch. If you have the money and time, this is a great upgrade on the 94-97 Birds. Another upgrade is a larger external cooler. If you have the money, a larger fluid cooler is a good idea to keep your fluid temperature down. Deep sump pans and new accumulators are another thing to consider. The birds of the 70’s had a nice big cooler… In comparison, the ones on our modern Thunderbirds is undersized for the job. Especially for those who live in high altitudes or hot arid climates. A new larger cooler will prevent your fluid from breaking down and will hopefully eliminate the need for frequent fluid changes.

Since my Torque converter replacement (under extended warranty) in 2000 I have changed my transmission fluid every twenty-five thousands miles using MERCON® V and a bottle of Prolong each time. I now have close to 92,000 miles on the car without any problems. Hope this will work for some of you other folks out there. For more complicated issues with your 4R70W I suggest visiting the Thunderbird and Cougar Club of America at http://www.tccoa.com there is a wealth of technical information that will assist you.

Brandon Lewis