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Well, I finally have an answer to what happened in my 2015 Mustang GT on the road course

Exp. Type
Exp. Level
5-10 Years
York, SC
I drove my 2015 Mustang GT at Carolina Motorsports Park in October 2020 and had a super weird issue where oil was coming through my JLT CAI and onto my suspension and then onto my driver side brakes, wheel and tire. This caused an unscheduled off track excursion that ended with my car against a tire wall and a broken knuckle on my left hand.

I have always wondered WTF happened, and today I found this YouTube video

Apparently there is a design flaw in the baffle of the driver's side valve cover that will allow oil into the PCV system under hard acceleration and hard right turns. CMP is 14 turns, 10 of which are right turns. Mystery solved!

So now at least I have an answer. The fix is to buy new valve covers and replace both sides, just in case. IMO the TSB does not go far enough.

In April of 2021 I traded my 2015 for a 2018 and turned it into my track car, so I won't have this problem, but just in case any of you have 2015-2017 GTs that you are tracking, I thought you might like to know about this problem before it bites you too.
Exp. Type
Exp. Level
3-5 Years
GT350 cover fixed it for me, only needed it on the left side, it only was smoking and puking oil on rights.
A couple years ago when I was dealing with this I tried to get the GT350 part number and it was on backorder everywhere with no ETA. The GT500 kit M6067M52S was just coming out and I took a chance assuming it would have the same baffling as the GT350, it did.

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