Does this look like imminent PTU failure

Discussion in 'Generation 4 - Maintenance & Troubleshooting' started by Citationdoc, Jan 31, 2017.

  1. Citationdoc

    Citationdoc SHO Member

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    Howdy folks,
    Got the car up on jackstands today for tranny fluid servicing and general undercarriage inspection. Noticed wet fluid on the right bottom of the PTU, Where the right front driveshaft goes into the PTU. This stuff is definitely NOT gear oil, looks more like transmission fluid. Is this indicative of the seal between the tranny and the PTU failing? I also noted a fair amount of oily crud on the top of the PTU, where the (I'm assuming) vent is. There is a rubber hose going into top of PTU that I believe is a vent line? So are these indications of PTU getting ready to self destruct? I've attached some pics of the "wet" fluid on bottom right, and some other, older residue as seen looking forward where rear driveshaft enters PTU

     

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  2. SHOdded

    SHOdded SHO Member

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    Your SHO is a 2013, it should have an extended PTU vent that you can see the cap on, coming out near the master cylinder in the engine bay. That would be the rubber hose you mention. Reference this TSB to get an idea
    http://www.revbase.com/BBBMotor/TSb/DownloadPdf?id=171259

    Red fluid = compression seal leak between transmission & PTU. If the older accumulation does not smell like gear oil, then it is probably trans fluid that has gathered grime. It is rare that there is a leak between the PTU and driveshaft (connecting PTU to RDU), but it can happen, especially as the driveshaft mount bearings wear out. In which case you should also inspect the RDU at the driveshaft joint to see if there is a leak at the pinion seal there.

    TSB for PTU compression seal leak, part numbers you will have to confirm with VIN on fordparts.com, as the TSB is for a 2010
    http://www.revbase.com/BBBMotor/TSb/DownloadPdf?id=176591

    There is a TSB 14-0032 for an AWD - LEAK FROM PTU, but unfortunately I do not have a copy to link to ... you CAN get one by subcribing to an online service like alldatadiy, chiltons, etc.

    I think the PTU is fine (especially since it has been symptom free), but the compression seal definitely needs to be replaced since the leak is active.
     
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  3. Citationdoc

    Citationdoc SHO Member

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    Hi Manu,

    Thanks as always! Just to be clear, would a compression seal leak manifest as fluid seeping from the outer seal of the PTU? There was no evidence at all of a leak between the PTU and the transmission, only from where the right front drive shaft goes into the PTU. Is the driveshaft isolated internally from the PTU gears (thus allowing fluid to migrate from compression seal along driveshaft and out the driveshaft seal)?
     
  4. Mitral

    Mitral SHO Member

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    Did you find out what was wrong with your car. My 2010 might have the same problem.
     
  5. Citationdoc

    Citationdoc SHO Member

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    Haven't taken in to look at/replace the compression seal that Manu suggests is the issue. Waiting for the tax return to come in, then will get that looked at when I install new exhaust
     
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  6. Mitral

    Mitral SHO Member

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    My mechanic checked out the car and saw there was a very slight leak between the ptu and the transmission. He was more concerned for a leak between the ptu and the axle. He quoted $500 for replacing both seals and 200 of it is only the axle. Should I spend the 500? Does this mean my ptu is also toast?
     
  7. SHOdded

    SHOdded SHO Member

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    PTU is probably fine. Leaks happen. Did your mechanic also verify the driveshaft bearings and the rear pinion seal? Those are the two things I would look at in addition to make a decision.
     
  8. Mitral

    Mitral SHO Member

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    Thanks Manu! I will have the mechanic check the rest too. I was under the car and didnt see any leaks in the RDU
     
  9. SHOdded

    SHOdded SHO Member

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    The output shaft seal replacement doesn't look any more difficult than the intermediate shaft seal R&R. Only extra step is the need for driveshaft indexing. How much of the quote is for parts, do you know?
     
  10. Mitral

    Mitral SHO Member

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    I think he said the 2 seals are about $40 and $460 in Labor.
     
  11. SHOdded

    SHOdded SHO Member

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    Is this a shop you regularly frequent, dealer/non-dealer? If so, they likely are quoting a fair price, the quote is like 4+ hrs at an independent, 3.5 or so at a dealership. Consider that removal of the PTU takes about 2 hours (don't have to do that for these seals), and I think the price should be at least $100 lower. But that's IMHO.
     
  12. Mitral

    Mitral SHO Member

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    Is a shop I have been using for over a decade. He said worst case scenario will be $500. If he is able to get the work in less time he might be able to knock $50-100 off. I have given him a lot of business and the guy is trust worthy.
     
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  13. Mitral

    Mitral SHO Member

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    I dodged a bullet :). The only leak was between the axle seal and the PTU and no leak between the PTU and the trans. Cost was under $200 to fix!!!!
     
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  14. SHOdded

    SHOdded SHO Member

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