Author Topic: Fiat 9.55535-GS1  (Read 150 times)

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Fiat 9.55535-GS1
« on: January 11, 2022, 12:13:28 PM »
Does anyone know what the Fiat 9.55535-GS1 spec stipulates apart from ACEA C2 and SAE 0W-30? Thanks.

Colin Edwards

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Re: Fiat 9.55535-GS1
« Reply #1 on: January 13, 2022, 09:47:43 PM »

Given it relates to a specific oil viscosity (relatively low) it probably mandates a high viscosity index and low Noaks volatility rating.  A very high spec oil!
The high viscosity index means is shouldn't lose much viscosity when hot and a low volatility rating (%) means the oil will evaporate less when sprayed up onto the base of the piston crown.  High output direct injection engines featuring oil cooled pistons (like the Alfa Multiair) will evaporate a fair bit of their oil, with a lot of it ending up on the inlet valves if the Noacks % is too high.  Fair chance this Fiat spec goes some way to addressing this issue.
The multiair in my Abarth uses almost no oil now that I use a Fiat 9.55535-S2 compliant oil. 
« Last Edit: January 13, 2022, 09:53:59 PM by Colin Edwards »
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