Not a part, but the first question on almost every transmission fault, which is why it has a page of its own. Automatic transmission fluid is a hydraulic medium, a coolant and a friction modifier at the same time — it carries the pressure that applies the clutches, and its friction characteristics determine how those clutches take up. That last role is why fluids are not interchangeable: a fluid meeting the wrong specification can produce shift complaints indistinguishable from a failing solenoid, and topping up with whatever was on the shelf is an invisible and surprisingly common cause of exactly that. Check level, then condition, then specification, before anything is diagnosed. Dark fluid that smells burnt has been overheated and its friction modifiers are spent; the damage that caused is cumulative and does not reverse when fresh fluid goes in.
Also known as: atf, transmission oil, gearbox oil, auto trans fluid, trans fluid, gearbox fluid, dexron, mercon
Referenced by 308 codes
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The AL4 — sold as the DP0 by Renault — is in a very large number of cars: the automatic 206 and Pars, the 307 and 407, the Xsara and Xantia, the Mégane and Scénic. It is a competen...
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