Would an overheated engine cause the automatic transmission.(87 towncar,
5.0 L) to fail? Last summer the engine over heated. Coolant was boiling out of the overflow. Engine was overheated for about 3 miles and 15 minutes. Within two days of fixing the overheat problem the auto trans started slipping in 3 rd and 4th speed and how to be rebuilt.
Overheating of the transmission will kill it in very short time. And I would assume that, because of what happened to your engine and the radiator (from which the transmission derives most of its cooling), you probably fried the transmission.
There is a table, somewhere on the internet, of temperature versus approximate time to failure for a tranny. The hotter it gets, failure is measured in hours or minutes.
Here is a link to one variant of the temperature versus miles to failure chart
If the engine coolant was severely overheated or lost, the trans may overheat very quickly. Another problem that may exist on your 1987 car is failure of the transmission throttle cable bushing. The original was "plastic". A metal replacement is available from the dealer and, probably, other sources. Should that bushing be missing, broken or badly worn, thhe transmission control pressure will be reduced resulting in slippage which will overheat the trans and burn the clutches very quickly. Failure may not be immediately apparent until the trans stops working. The shop which rebuilt the trans should have made sure the correct updated bushing was installed at the time of rebuild to preclude future control pressure problems and recurring failure. If this was done along with other updates, you should have no further worries about the trans.
Engine damage from overheating may not become apparent or have any affect for some time if ever. A well maintained engine may operate several hundred thousand miles even after being overheated. Even so, overheating is detrimental to both the engine and transmission.
Lugnut
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.