GMC 2003 Sierra - Manual (Page 320)

Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your Kras lha( ihey can actually ride on ihe
water. This can happen it the road Is wet enough and
you re going tast enough, w/hen your vehicle is
hydroplaning^ bt has little or no contact with the road.
Hydroplaning doesn’t happan often. Bui ¡1 can if
your tires do not have much treed or if the pressure in
one or more is low. !t can happen if a lot o( water is
standing on ihg noad. If you tan see retlectkms
from trees, telephone poles or other vehicles, and
raindrops "dimple" the water's surface, there could 1зе
hydroplaning.
Hydroplaning usually happens al higher speeds. There
just isn't a hard and fasi rule about hydroplaning.
The best advice is to slow down when M is raining.
Driving Through Deep Standing Water
jVon'ce: tf you drive too quickly through deep
puddles or standing water^ water can come in
through your engine’s air intake and badly damage
your engine. Never ddvo through water that is
slightly lower than the underbody of your vehicle. If
you can't avoid deep puddles or standing water,
drive through them vory slowly.
Driving Through Flowing Water
A CAUTION;
Flowing or rushing water creates strong forces,
ff you try to drive through flowing water, as you
might at a low water crossing, your vehicle can
be carried away^ A$ little as six fnches of
flowing water can carry away a smaller vehIcFe.
If this happens, you and other vehicle
occupants CDU Id drown. Don't ignore police
warning signs, end otherwise be very cautious
about trying to drive through flowing water.
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