PTU drain plug drill and tap

[Lowtalker]

First off I'm new to the forum and this subject has been discussed rather thoroughly on this site. So, I apologize for beating a dead horse.

Back in Sept this year I purchased a used 2013 Edge SEL AWD with about 50k miles. During my test drive I had it put on a lift to inspect the underbody rust as it was from the NE. There were no signs of leaks anywhere. Rust seemed cosmetic. Not too long after I purchased it, I started noticing a harmonic droning or vibration at 45 mph and higher. First thing I did was check tires. They all had sidewall cracking so, I replaced them with Michelin Latitudes. The sound actually got worse. I had the tire place rotate and re- balance the tires but the sound stayed the same. Went on a 1000 mile trip. The sound never got worse but definitely was bothersome. My next step was to evaluate the brakes and check each wheel for hub wear. However, a few days after returning, I noticed a black spot where I had parked. I looked underneath and a large amount of what ended up being gear oil from the PTU had essentially leaked all over and blew everywhere underneath.

 

Flash to the dealership. I'm still covered under the power train warranty. So, I take it in, describing that I was investigating a vibration when I noticed all of the oil everywhere. Ultimately, they replace the PTU but told me they had to write it up that I was hearing grinding noises when I was turning at low speeds. He said otherwise a leak wouldn't be covered under warranty. In fact, he said it looked like the PTU had been "hit" by something that cracked the case thus, leaking out all of the fluid. I didn't argue with the service guy, since I got the repair I wanted which was a new PTU under warranty. While I am certain I did not, if I had hit something that managed to crack the PTU then I most likely would have filed it on my insurance. All this being said, I just can't figure out why all the BS about the grinding steering noises. It sounds like PTU failure is a common problem... even the cracked housing part.

 

Really just curious if anyone relates to this. I feel fortunate to have gotten the repair. But, I am definitely concerned about future failures after all I've read.

 

Thanks.

 

Oh yeah, the droning vibration went away. Sorry for the long post.

[WWWPerfA_ZN0W]

A leaking PTU used to be sufficient cause for replacement. Ford is moving towards fixing the internals now. Maybe that's why they wrote it up as they did.

 

As to the case cracking, never heard of that in an impact-less situation.

[Lowtalker]

I did not ask to see the cracked part. I was satisfied, at least, that they replaced it. As far as the PTU actually being cracked, I don't really know. Either the crack was present when I purchased it and yet still not leaking, or it is just part of the story the service department cooks up for a warranty repair. I have certainly not impacted anything with this car. Seems like a difficult thing to be impacted by something. Oh well, I guess I'll be more careful.

 

So, it sounds like from some of the things I've read that I might need to make the PTU part of normal maintenance. Any thoughts on that? Would suctioning out and then refilling be sufficient? How often? Read one post where someone drilled and tapped the PTU for a drain plug. I like the idea. I might be nervous trying that, though.

 

On a side note. I believe the PTU was leaking a couple thousand miles before I noticed it. I was traveling across the country stopping here and there, rest areas, hotels, etc. It is very possible that it was dripping and I simply didn't notice until after I got home. Based on someone's description of smelling the leak when they got to a stop after highway driving, I'm pretty sure I was smelling it from Colorado to NC. But I had recently gotten my oil changed and just chalked it up to that. Normally I'd change it myself, but I was in the middle of a long road trip. For the record, I had the oil change place only change the oil and specifically told them not to check fluids under the car. Don't really want them messing around down there.

[WWWPerfA_ZN0W]

Mostly highway? 30K mile intervals for the PTU/60K for the RDU should be sufficient. Mixed or mostly city, cut that in half. Yes, drain & refill should be sufficient. Drain plug definitely makes it easier to do a complete service in one shot, but not necessary. Use the time to find a reputable shop (non-dealer) that can take the info on this forum and put the plug in for you. I get the nervousness. Having just gotten a new PTU, what to do, right? Keep on a strict fluid change regimen, and find a place to change out the RDU fluid as soon as possible so you can get on a proper schedule.

[1004ron]

Mostly highway? 30K mile intervals for the PTU/60K for the RDU should be sufficient. Mixed or mostly city, cut that in half. Yes, drain & refill should be sufficient. Drain plug definitely makes it easier to do a complete service in one shot, but not necessary. Use the time to find a reputable shop (non-dealer) that can take the info on this forum and put the plug in for you. I get the nervousness. Having just gotten a new PTU, what to do, right? Keep on a strict fluid change regimen, and find a place to change out the RDU fluid as soon as possible so you can get on a proper schedule.

Is the RDU oil change straight forward - I guess you need to use an oil extractor, or do folks pull the rear cover and replace the gasket?

[WWWPerfA_ZN0W]

Same as PTU except easier access to the fill plug. No drain plug yet on the RDU. Most do not take off the cover to drain. The "gasket" is RTV silicone.

[chefduane]

+1 I just did a 'suck and fill' on my RDU. Pretty easy to do.

[1004ron]

Took a look under rear end, and as can be seen in the photo of the RDU, I'll most certainly not be pulling the rear cover, but good to hear that 'suck & fill' works well.

 

One more question, what oil is recommended by the forum members - the owners manual doesn't specify synthetic, so would syn be better or could it cause problems?

I was thinking of using this oil: Royal Purple 75W-90 Synthetic Gear Oil 01300

Edited December 10, 2017 by 1004ron

[chefduane]

RDU spec is Motorcraft 80w-90 Premium Rear Axle Lubricant XY-80W90-QL about 2.4 Pints/1.15L or until she blurbs a bit out of the fill hole.

 

PTU spec is Motorcraft 75w-140 Synthetic Lubricant XY-75W140-QL/WSL-M2C192A 12oz/.35L or until she blurbs out the fill hole.

 

If you want to strictly stay with spec then go with the Motorcraft, but I would think that the Royal Purple 75W90 would probably be ok for the RDU.

 

Disclaimer: This is spec for a 2011 Limited AWD.

[WWWPerfA_ZN0W]

The product choices from Motorcraft are listed here:

https://www.fcsdchemicalsandlubricants.com/main/category.asp?select=%5BTransaxle%20Fluid%5D

 

Additive Friction Modifier SAE 75W-140 Synthetic Rear Axle Lubricant SAE 75W-85 Premium Synthetic Hypoid Gear Lubricant SAE 75W-90 Premium Synthetic Transaxle Lubricant SAE 75W-90 Synthetic Axle Lubricant SAE 80W-90 Premium Rear Axle Lubricant

 

Looks like the 80W90 product is not full synthetic but the 75W90 is. Anyhoo, x2 on chefduane's comment. RP 75W90 will be a good step up, Redline and Amsoil would be the best non-custom products available.

 

https://www.redlineoil.com/75w90-gl-5-gear-oil

https://www.redlineoil.com/Content/files/tech/ShockProof%20Gear%20Oil%20Tech%20Info.pdf

https://www.amsoil.com/AmsoilGarage/internal/vehiclelookuppage.aspx?url2=2016+FORD+EDGE+P

Edited December 10, 2017 by WWWPerfA_ZN0W

[1004ron]

Thanks for all the useful comments.

 

I decided to order 3 quarts of the Redline GL-5 - is that best suited, or the standard non-GL-5 ?

 

Red Line 57904 (75W90) Synthetic Gear Oil - 1 Quart

[WWWPerfA_ZN0W]

That one should work well. I would say even to go with the SuperLightweight Shockproof, but that is not Redline approved for our applications. I think a chat with them would be merited to help make your decision if you want to stick with "approved".

[1004ron]

That one should work well. I would say even to go with the SuperLightweight Shockproof, but that is not Redline approved for our applications. I think a chat with them would be merited to help make your decision if you want to stick with "approved".

Thanks.

I'll stick with the GL-5, seeing as the application isn't really very strenuous.

 

I have been using the Shockproof in my Harley transmission for many years.

 

Now to find a pump that fits the smaller opening on the Red Line bottles.

Edited December 14, 2017 by 1004ron

[NoDTMF]

I have a 2016 titanium. Are these the fill and drain plugs? The fill plug by the exhaust bolt. And below it a much smaller looking plug, but not really at lowest point of PTU. So not all oil would drain. Fill plug looks to be a pain to get to. Note. Not even sure if this is the PTU.

 

Interesting. I didn't take a picture, but on my 2017 sport, the drain plug is in a different location, at the very bottom, pointing down. When drained I got 22oz.

[mwillie42]

Hi all

 

long time lurker here, owned a 07 ford edge awd since 2011.

 

I am a pretty stong audi mechanic, and I refuse to drive anything not AWD as my personal vehicles.

 

Anyways cut the crap and into the meat and potatoes of the issue.

 

There are 3 failure modes for leaking of the PTU.

First the Shaft seal will leak from the output shaft seals on the Passanger side of the vehicle. Ford pretty much has this covered as updated parts, and proceedures to replace the offending seals with newer design units and ensure a leak free setup. I'm not really going to go into it much since everyone and their brother has done so before.

 

Second, the compression seal between the PTU and Transmission can go. From what I do know this is a pretty rare event. The seal is held between the transmission and PTU pretty securely and no debris can really make their way there. If you EVER remove the PTU for whatever reason, replace that seal!

 

Last, and the one i want to focus some effort on is the VENT leak.

This is where the PTU will start vomiting up fluid from the PTU case vent.

I had this happening to me with reasonable frequency to cause concern. It normally only happens when I am driving over 60mph/100kph and leaves a nice immeadiate puke once parked or stopped but never leaves puddles in the driveway (mostly cause i slow down to well under 60mph long before I get home)

It causes the stinky smell when the gear oil drips onto the exhaust at stoplights.

 

Anyone looking at their PTU and seeing alot of black stains and fluid on it can clearly distinguish a VENT VOMIT from the fact there appears to be no leaks around the Pass Side Shaft seal. It make confuse you to think it is a compression seal, but it is not as the stains proceed up higher on the PTU. If you have a small mirror and flashlight you can confirm it by looking above and down onto the PTU.

 

Ford may say that the PTU is overfilled and causing this, however that is only true if it actually is overfilled. By design the transmission cannot leak ATF directly into the PTU so this is implausible, and I know most owners are not running around overfilling their PTU's just because..... sooo....

 

I bought a shot PTU on eBAY to disassemble and see WTF is going on.

I will post pictures but that will wait for tomorrow.

 

The problem is the vent case is setup with its own little oil/air separator. However the problem is this is defeated because of the gear oil selection ford has chosen. No big fault in them other than saying the PTU is filled for life. IMHO the PTU should be flushed after the first 15K with new fluid, and this means installing a drain plug in the PTU (easy and something I plan to do).

 

Anyways the gear oil gets a moly additive which is great! but the gear oil also seems to be of a quality not high enough to stand usage in the PTU for the real life of the vehicle (7-10 years in my opinion). What is worse, is if you actually do develop a low gear oil event due to a seal leak, and the PTU takes a beating from it, well now you have even more crap that the oil has to deal with and will definately plug up the case vent system.

 

What is going on is there is a large ring gear to finally drive the center shaft, this gear spins right beside the VENT. Now before all you jump on board and say this is a design problem it is not. There is nothing wrong with this and once i post pics you will understand. The problem is when the vent system does fail this ring gear will act as a pump and force lube up into the vent system for it to vomit forth all over the ptu and exhaust.

 

What is causing the vent system to fail then? debris. normal break in debris, metal filings naturally caused during the normal wear in process, along with the moly additive acting like glue, and lastly the lower quality gear oil used.

This turns the gear oil into a tar/grease that plugs up the designed in oil/gas separator in the vent for the PTU. With that oil gas separator gone and the ring gear now starting to pump oil right next to the vent is the reason it is being forced out the vent.

 

The solution is if you know your PTU is good 2 fold. Clear/clean the vent system, and replace with high quality gear oil.

 

1. you could just do successive fluid changes until all that grease is disolved away. Time consuming and maybe annoying too. but it would eventually work.

 

2. you could also install a drainplug and with the car in the air, pop the vent cap off and spray brake clean in there hoping it works. While your at it you will also be spraying any debris back into those lovely taper bearings:D so I do not recommend this.

 

3. You could do what I recommend. and disassemble the PTU. This is tedious but easy. Once it is off the car, it is mandatory that you knock off the deflector, but you do not need to remove the seals (although why you wouldnt replace them at this points baffles me).

 

I beleive it may even be possible to disassemble the PTU on the car, but you would still need to replace the Pass side shaft seal/deflectors.

There are a few 10mm bolts holding the casing half on, spin those off after you shatter off the deflector and the rest is simple physics of tapping and wiggling the case cover off it's alignment dowels.

 

Once you see the PTU you can remove the large ring gear and or all the gears and rinse it down. I normally use paint thinner or parts cleaner, but do not use water based stuff, you want to avoid rust. make sure you do not lose track of the bearings positions or any shims, if you do your in for a big annoying time. Clean all the gunk out and inspect the output gears to the center shaft. My eBay unit suffered galling on the hypoid gears due to lack of lubricant, no big surprize considering where I bought it, but I knew it was for disection purposes.

 

If yours has been quiet but has minor gear wear, we might as well just keep going. You could get a new unit if you have warrenty or feel like spending the money, but in the mean time your original unit was working despite the damage, why stop now?

 

anyways assembly is reverse of removal, do not forget to seal up the case half with Ultra Grey sealant or ford sealant. Same they use on all their drivetrain stuff. I prefer the ultra grey and have been using it on Audi's for years with no issues.

 

I hope to improve this post with photos from the donor/experimental unit and then again update them with photos of my own PTU job on my Edge over the christmas holidays.

I will also provide people with the correct location for a 1/2 NPT drainplug on the PTU so they can make their own mods and improvements.

 

NOTHING and I repeat NOTHING should ever be "Filled for life" total bullshit.

Ford, Audi, Rolls Royce, does not matter. everything needs a fluid change interval.

 

YMMV

 

This post is exactly what I am experiencing with regard to the vent. The drain/refill seems like the best remedy. Any pics and lube spec recommendations?

[mwillie42]

This post is exactly what I am experiencing with regard to the vent. The drain/refill seems like the best remedy. Any pics and lube spec recommendations?

[1004ron]

This post is exactly what I am experiencing with regard to the vent. The drain/refill seems like the best remedy. Any pics and lube spec recommendations?

 

 

This post is exactly what I am experiencing with regard to the vent. The drain/refill seems like the best remedy. Any pics and lube spec recommendations?

There's an echo in here.

[Tightanium]

Interesting. I didn't take a picture, but on my 2017 sport, the drain plug is in a different location, at the very bottom, pointing down. When drained I got 22oz.

5 months later and a response. I guess it was a difficult question. Kidding aside, if the lower plug drains 3/4 of it out I could suck most the rest of it out. Lower plug is easier to get to.

[1004ron]

5 months later and a response. I guess it was a difficult question. Kidding aside, if the lower plug drains 3/4 of it out I could suck most the rest of it out. Lower plug is easier to get to.

Seeing as yours doesn't have a lowest point drain like the Sport's do, it would be best to suck out as much as you can after draining from the plug you have.

[JSchneid]

I crawled under my 2016 EDGE Titanium 2.0L AWD to have a look at the PTU. I was pleasantly surprised to find that my PTU has a drain. I was not happy to find that the PTU was leaking where the passanger side drive shaft exits the PTU. This EDGE was 1 year old yesterday and it only has 7100 miles. In one of the attached images the leak can be seen along with the fill plug just above that. The other image shows the drain plug which is on the bottom of the PTU pointing straight down. This PTU looks different than other photos I have seen of PTU's. This PTU has fins and both fill and drain plugs are torx.

[1004ron]

I crawled under my 2016 EDGE Titanium 2.0L AWD to have a look at the PTU. I was pleasantly surprised to find that my PTU has a drain. I was not happy to find that the PTU was leaking where the passanger side drive shaft exits the PTU. This EDGE was 1 year old yesterday and it only has 7100 miles. In one of the attached images the leak can be seen along with the fill plug just above that. The other image shows the drain plug which is on the bottom of the PTU pointing straight down. This PTU looks different than other photos I have seen of PTU's. This PTU has fins and both fill and drain plugs are torx.

That's not a low point drain as found on the Sport, so you'll still need an extractor to get what remains after you drain from that plug.

 

I wonder why they did it like that, why not a drain plug as seen on the Sport?

[JSchneid]

That's not a low point drain as found on the Sport, so you'll still need an extractor to get what remains after you drain from that plug.

 

I wonder why they did it like that, why not a drain plug as seen on the Sport?

I have not seen a photo of the PTU on the Sport so I don't know how it differs from mine. This drain is on the bottom of the PTU at it's lowest point pointing down to the ground. Do you have a photo of the Sport version? In looking at this image again I can see why you thought it was not at the low point, it appears to be on the side in this photo but it is on the bottom, my camera is pointed up and to the right slightly as I lay on the ground.

 

Edited January 29, 2018 by JSchneid

[1004ron]

I have not seen a photo of the PTU on the Sport so I don't know how it differs from mine. This drain is on the bottom of the PTU at it's lowest point pointing down to the ground. Do you have a photo of the Sport version? In looking at this image again I can see why you thought it was not at the low point, it appears to be on the side in this photo but it is on the bottom, my camera is pointed up and to the right slightly as I lay on the ground.

 

That photo shows a plug on the side which definitely doesn't look like the lowest point, unless its the orientation of the photo.

 

 

http://www.fordedgeforum.com/topic/10914-ptu-leak-failures/?p=170489

 

See photo 5 in post 466 in this thread - that is the Sport PTU and the drain plug facing the floor.

 

Same comment made below.

 

 

Interesting. I didn't take a picture, but on my 2017 sport, the drain plug is in a different location, at the very bottom, pointing down. When drained I got 22oz.

Edited January 29, 2018 by 1004ron

[Wood]

This place is awesome. I just picked up a 2012 limited and came in to find out what’s going on with these things. I found this thread and the video and decided it all made sense to me. A quick stop at amazon and 2 days later I’m drilling into my beauty in the garage. Thanks to all the good info it all went nice and smooth. Thanks for the tips guys! A couple hours work (I took my sweet time) and $40 including fluid is worth the piece of mind. I flushed it but I’m going to drive for a couple weeks and then dump and fill again. Figure every 5K until fluid looks good. Then just do it every 60K. Rear diff and transmission are next.

[JSchneid]

I think this photo does a better job of showing the drain at the very bottom of the finned PTU, pointing down.