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The driver's side valve cover pulls in fresh air from in front of the throttle body (which is atmospheric pressure, and not a vacuum source), to keep fresh air coming into the crankcase, which balanced the vacuum pulled on the passenger side valve cover at the opposite end of the system. Again, just like the factory routing, and all of the "hoses pulled flat" and honking noises have gone away. We had initially switched to a simple breather system during the ECR race weekend, but with 3 race weekends run in the weird "high crankcase vacuum" mode we think that is when the rear main seal was damaged. The old routing kept
filling the catch can with oil.
You can see the extra hose bib that was added (TIG welded) to the gold foil wrapped aluminum intake tube in the two pictures above, when we switched the hoses to a more traditional PCV style routing. We even added the PCV valve back to the passenger side valve cover (note the blue color of the one-way check valve on the PCV coupler; the black coupler on the driver's side is just a straight thru connector). We will test this new routing at a track test day / possible TV shoot this coming weekend, but I'm confident this will work just like stock, because it
is just like the stock routing now but with the catch can in place.
Basically we created a problem, listened to people tell us to keep doing it the wrong way, chased our tails, damaged the rear main seal, and then undid the mistake and went back to a logical PCV routing system. Sometimes you have to ignore advice and just do what makes sense, what works.
Repair Work to Rear Main + Clutch
So by now it was late November, many repairs and fixes had been done to help sell the car and put to bed every little nagging problem, except one: the leaking rear main seal. At this point and we still had every intention of selling the red TT3 Mustang, and I couldn't let anyone buy the car with a known oil leak. So I asked the guys in our shop to yank the transmission out for a look at the rear main seal. This meant we had to drop the after-header exhaust, the starter, the driveshaft, unhook the shifter, and then pull the transmission. Lots of fun. Kyle tackled this rear main seal + clutch replacement work in 6 hours and 23 minutes, according to our
MyShopAssist logs (this service tracking system is used on all of our service work starting in mid 2013, even our own cars).
This was the first time
we had to pull the transmission out of our 2011 GT, as the service to 3rd gear last April was done by the dealer under warranty. The drivetrain in this car has been rock solid and I didn't expect to see any damage to the clutch, pressure plate or flywheel, other than possible oil contamination.
Once the transmission was out, the clutch, PP and flywheel, as well as the reluctor for the crank trigger had to come out to access the rear main seal. The seal replacement is actually very easy once all that is out of the way. The new part wasn't expensive at all ($11) and I was hoping that's all we would need to do - burn some hours making access to the seal, then replace this one part. Looking at the clutch disc surface you would think this was a brand new car, as it had almost
no noticeable wear. 18,000 miles and lots of autocross starts and thousands of shifts on track, and all of the friction and metal surfaces looked perfect on the clutch, flywheel and pressure plate. Amy and I are always easy on drivetrain parts, but there
was some damage... something quite strange.
Above are pictures of the 3 dowel pins in the stock flywheel (in 6 pieces, just as they came out). When Kyle pulled the transmission he noted that all 6 bolts holding the PP to the flywheel were
very loose. That's not good. And then when he pulled the PP off the 3 dowel pins fell out, as each had broken in half. WTF? I cannot say what happened here, except to note that this has all been apart before for some warranty work. The loose pressure plate to flywheel bolts must have allowed the pressure plate to wobble out the mounting holes, and that movement then broke the dowel pins. To me this meant the PP was not reusable, and I had questions about the flywheel. Could we have reused it all? Sure, and since we were selling the car so it would be no bother... but I don't play that way.
We weighed the OEM flywheel, of course, and at 22.3 pounds it was lighter than I originally thought it might be (but confirmed the numbers I was given by Fidanza). Would it be worthwhile to replace this with a 12-13 pound aluminum flywheel? Hmm.... not a lot of gain here, compared to some V8 cars we've dealt with that have 40-50 pound flywheels. Since I felt uncomfortable replacing
just the pressure plate, and we could not find the part number or a source for the 5.0 Coyote's flywheel dowel pins, we went ahead and
replaced all of it.
While this seems somewhat drastic, remember - this is a 6+ hour repair job, where the labor outweighs the replacement costs of the clutch/PP/flywheel parts. It is rare that you pull a transmission and
not replace at least the clutch disc. After doing some research and running out of time (we had the car in pieces, stuck on one of our lifts) we went back with the exact stock replacement parts sourced from Ford. The clutch, pp and flywheel are the same OEM pieces as what came out, just brand new and secured properly this time. All told it was about $500 in parts, and while we could have saved a little money with aftermarket replacement bits I didn't want to risk changing something that worked so well on a car I was about to sell. Most aftermarket clutches would have more pedal effort, and at this power level (420-430 whp) we obviously didn't need it, as we had never felt clutch slippage and noticed almost no wear on the clutch parts.
Going back together was fairly easy, and everything lined up perfectly. As you can see we are still running the stock shifter (less notchy than most SSKs) but do have the Steeda rear poly bushing in the body side mount and the Whiteline trans bushing insert as well, and Amy and I both like the positive shift feel and low shift effort. New pressure plate mounting bolts were secured in place on the flywheel
with red Loctite this time, which was obviously missing on the old bolts (they were clean and dry).
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