Cadillac 2011 DTS - Manual (Page 308)

Black plate (6,1) Cadillac DTS Owner Manual - 2011
Gasoline Octane
Use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular
unleaded gasoline rated at 87 octane or higher, but the
vehicle's acceleration could be slightly reduced, and
a slight audible knocking noise, commonly referred to
as spark knock, might be heard. If the octane is less
than 87, you might notice a heavy knocking noise
when you drive. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible. Otherwise,
you could damage the engine. If heavy knocking is
heard when using gasoline rated at 87 octane or higher,
the engine needs service.
Gasoline Specifications (U.S. and
Canada Only)
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or CAN/
CGSB‐3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines containing
MMT. See Additives on page 6‑7 for additional
information.
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