Hi,
I just got this info off another GTO forum. Hope it helps.

arty:
Document ID# 1848873
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Subject: Front Strut or Struts Leaking Oil - #PIC4141 - (07/20/2006)
Models: 2006 Pontiac GTO
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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Front strut or struts leaking oil.
Recommendation/Instructions:
On the 2006 GTO the oil in the front struts was changed to a lighter weight oil. This change may cause the front struts to leak after only a few thousand miles. The oil in the struts was changed back to the original weight oil on May 5, 2006 both in production and for service. If a strut or struts are leaking replace the leaking strut(s) with current GMSPO stock. All old GMSPO stock with the lightweight oil has been purged.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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