How much transmission fluid dexron 111 is needed for a 3.8 engine size of 1988 Buick Lesabre?

The amount of Dexron III (not Dexron 111) transmission fluid needed for a 1988 Buick LeSabre with a 3.8L engine depends on whether you're doing a drain and fill or a complete flush. There's no single definitive answer because some fluid always remains in the torque converter and cooler lines.

* Drain and Fill: A drain and fill will typically require between 3-4 quarts. This replaces only a portion of the fluid.

* Complete Flush (using a transmission fluid exchange machine): A complete flush will use significantly more fluid, potentially 8-12 quarts or more, as it circulates and replaces almost all the fluid.

Important Note: Dexron III is the correct fluid specification, not Dexron 111. Dexron 111 is an older fluid and is not compatible with modern transmissions. Using the incorrect fluid can severely damage your transmission. Always double-check your owner's manual for the *exact* recommended fluid type.

Before performing any fluid change, consult your owner's manual for the specific procedure and capacity for your vehicle. It's also best to check with a trusted mechanic if you're unsure about performing the fluid change yourself.