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Power Steering Fluid Foaming On a Cold Start - keywords cold duty fluid foam foaming leak md medium power start steer steering

Subject: Power Steering Fluid Foaming On A Cold Start

Models:2003-2008 C6500-C8500 Series
2003-2008 T6500-T8500 Series
with 7.8L Turbo Diesel Engine (RPO LG4 or LF8)



This PI was superceded to update Model Year. Please discard PIT4487A.


The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some customers may notice the power steering fluid foaming and leaking out of the power steering reservoir when starting the vehicle in cold weather (20 F (-7 C) or colder). When the concern happens, the customer may also experience little or no power assist at the same time.

Recommendation/Instructions:

Please do not replace any parts on the vehicle at this time. Engineering is working on a fix and this PI will be updated when a fix becomes available.

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.