PTU (Transfer Case)

[wwest]

Didn't I read somewhere that water cooling was added to prevent the PTO/PTU from over-heating..??

[druck52]

Didn't I read somewhere that water cooling was added to prevent the PTO/PTU from over-heating..??

 

 

nope, you didn't read that anywhere

[jcas]

Put me on list, 07 MKX, 15k on it (just picked it up 3 weeks ago used). First time driving with heater on, could smell oil burning at stop light. Has extended warranty so I just have to get it to dealer but that in itself is PIA.

Guys at work were busting on me to buy American and I joked that "I did but it better not be in shop every month", guess i jinxed myself.

[CowwFace]

Hey Folks,

 

I'm currently working on a deal on a 2007 Ford Edge with 51k miles. I really like the car, how it drives and looks. However on the test drive, we did get the smell of burnning transmission fluid at one stoplight. I searched that and ended up here. It seems like the earlier posts had mutiple attempts of getting this leaking seal fixed. I'm not thrilled with the idea of a diverter shiled to let the leak avoid the hot exaust either...

 

My question is: Has anyone had the problem FIXED? can it be fixed or is it just something that has to be lived with?

 

Thanks,

Phill

[wwest]

I am of the quite firm belief that the use of the rear drive is causing the PTU, PTU lubrication, to overheat.

 

I'm pretty sure that Ford has solved this problem in the more current models by simply relaxing the firmware specifications for the use of the rear drive coupling. If you are having problems with earlier models then the best fix procedure is to add an inline switch to the reardrive coupling clutch electric clutch. Leave the circuit open unless you are on aderse roadbed conditions. Personally I would even go so far as to be able to open the circuit when F/awd functionality is needless and fullyv close the circuit to a SOLID 12 volt source when it is needed.

 

You would have to be very CAREFUL in remembering to open the circuit on highly tractive surfaces.

 

I do not own ANY form of this F/awd technique, all I say in that regard is from book-learning.

[akirby]

I am of the quite firm belief that the use of the rear drive is causing the PTU, PTU lubrication, to overheat.

 

I'm pretty sure that Ford has solved this problem in the more current models by simply relaxing the firmware specifications for the use of the rear drive coupling. If you are having problems with earlier models then the best fix procedure is to add an inline switch to the reardrive coupling clutch electric clutch. Leave the circuit open unless you are on aderse roadbed conditions. Personally I would even go so far as to be able to open the circuit when F/awd functionality is needless and fullyv close the circuit to a SOLID 12 volt source when it is needed.

 

You would have to be very CAREFUL in remembering to open the circuit on highly tractive surfaces.

 

I do not own ANY form of this F/awd technique, all I say in that regard is from book-learning.

 

The PTU sends power to the rear differential all the time. The rear differential determines when to engage the rear wheels, not the PTU.

 

You need new books.

[wwest]

The PTU sends power to the rear differential all the time. The rear differential determines when to engage the rear wheels, not the PTU.

 

You need new books.

 

"..The rear differential determines..."

 

No, in reality the electromechanical clutch housed within the rear differential case is used to control, linearly control, the rear drive apportionmant.

 

You miss the point. The ENTIRE drive train is put under additional stress when the rear drive clutch is engaged. In the past, apparently, the PTO/PTU has proved to be the weak point, weak link in the chain. Mazda, seemingly, approached the problem via additional cooling of the PTO. One must assume therefore that ford simply "derated' the f/awd capability via firmware modifications.

[Waldo]

I guess book learning doesn't teach you much about manufacturing. When you build hundreds of thousands of parts at relatively quick line speeds, you end up with a lot of tolerance variation. If you end up with a couple of parts on opposite ends of their tolerance ranges, you end up with problems like leaks.

 

From what I understand (from real sources, not books), the issue with the Ford PTU is a tolerance stack-up between the halfshafts, the seals and the bearings the link shafts mount to that essentially prevent the shaft from sitting straight in the seal. Ford is/has been working on eliminating these conditions, they have not made any changes to the software strategy. It has nothing to do with temperature.

[wwest]

I guess book learning doesn't teach you much about manufacturing. When you build hundreds of thousands of parts at relatively quick line speeds, you end up with a lot of tolerance variation. If you end up with a couple of parts on opposite ends of their tolerance ranges, you end up with problems like leaks.

 

From what I understand (from real sources, not books), the issue with the Ford PTU is a tolerance stack-up between the halfshafts, the seals and the bearings the link shafts mount to that essentially prevent the shaft from sitting straight in the seal. Ford is/has been working on eliminating these conditions, they have not made any changes to the software strategy. It has nothing to do with temperature.

 

"..It has nothing to do with temperature..."

 

 

Having experienced, apparently along with many others, the horrid odor/smell of OVER-COOKED PTO lubrication I think I'll just stick with my theory. And I am NOT speaking of 70 weight lube leaking on hot exhaust components.

[akirby]

Your theories are nothing more than guesses based on your gross misunderstanding of how things work.

[wwest]

Your theories are nothing more than guesses based on your gross misunderstanding of how things work.

 

 

Just EXACTLY what we should expect from a Ford Edge....

 

FANATIC....!!

[Waldo]

"..It has nothing to do with temperature..."

 

 

Having experienced, apparently along with many others, the horrid odor/smell of OVER-COOKED PTO lubrication I think I'll just stick with my theory. And I am NOT speaking of 70 weight lube leaking on hot exhaust components.

 

The PTU lubrication is cooked after it leaves the PTU and lands on the exhaust. The exhaust is much hotter than the internals of the PTU. This has been well documented. I'm not quite sure how else you could smell it.

[wwest]

The PTU lubrication is cooked after it leaves the PTU and lands on the exhaust. The exhaust is much hotter than the internals of the PTU. This has been well documented. I'm not quite sure how else you could smell it.

 

Other than the seals having already been blown, compromised, there is always a "breather" method somewhere/somehow in any automotive gear box.

[anpbabaki]

another smoker here..09 SEL with 9K miles. Stopped at a light and car filled with smoke through the heat vents...dealer says PTU seal but its on national backorder and he had 6 others waiting for the same part...That was 9 days ago, they still have not gotten the part.

[wwest]

I would have to assume that T-case stress would be increased by towing, but would this cause a leak?

 

 

I don't know about the Edge, but my '06 Pathfinder is rated to tow 6000lbs and I do tow 4500-5000 most weekends (deck boat). The service manual says to change the Transfer Case (as well as Transmission/front diff/rear diff) fluid at 30,000miles if towing, 60,000 if not towing. SO I assume there is increased stress/wear on that area under heavy load.

 

BUT what I don't understand is how this would cause a leak. Internal wear is one thing, but it shouldn't be blowing out the seal and making a leak.

 

I WOULD take the boat to a certified scale (loaded and ready for the water) and get it weighed though, this way if you do end up having any issues w/ the warrenty you can quickly make a case that you were under your 3500lbs towing limit (or if you are above, you can get a new tow vehicle before you do blow something up).

 

I took the boat to a truck stop and drove my truck/boat on the scale and got a weight (truck on front scale, boat trailer axles on the rear scale so I could get both weights). Then drove off and unhooked the boat, came back on and weighed just the truck. Then I could calculate tongue weight/truck weight/boat weight and know what I'm really pulling.

 

 

"...but would this cause a leak...??..."

 

PTO STRESS....YES...!!

 

Stress = HEAT, heat means expansion of the volume of the PTO lubricating fluid, maybe even boiling of same........BLOWN SEAL.

 

Catch 22, put less lubricating fluid in the PTO so fluid volume when HEATED doesn't exceed case capacity, COOLING effect of the fluid is also reduced. Lubricating fluid is the MEDIUM through which HEAT is conveyed from the PTO ring, pinion, and bearings to the PTO case for dissipation.

 

Solution: Either reduce the functionality of the F/awd system (lower overall voltage duty-cycle to the rear drive engagement clutch) or provide additional cooling to the PTO as Mazda did.

[wwest]

The PTU sends power to the rear differential all the time. The rear differential determines when to engage the rear wheels, not the PTU.

 

You need new books.

 

 

The PTO "couples" engine drive HP to the rear electromagnetic clutch ALL the time, CONSTANTLY.

 

Engine torque is ONLY conveyed, thus HEATING the PTO, when that clutch is enaged.

 

Otherwise the PTO is only along for the Ride, sorta like the rear wheels of a FWD vehicle.

[wwest]

I guess book learning doesn't teach you much about manufacturing. When you build hundreds of thousands of parts at relatively quick line speeds, you end up with a lot of tolerance variation. If you end up with a couple of parts on opposite ends of their tolerance ranges, you end up with problems like leaks.

 

From what I understand (from real sources, not books), the issue with the Ford PTU is a tolerance stack-up between the halfshafts, the seals and the bearings the link shafts mount to that essentially prevent the shaft from sitting straight in the seal. Ford is/has been working on eliminating these conditions, they have not made any changes to the software strategy. It has nothing to do with temperature.

 

Agreed, basically.

 

With the stress added to the PTO with the rear drive engaged it will undoubtedly heat up. The metal case has a higher expansion ratio than the rubber (composite) seals and so....

 

And we could leave it simply at that, tolerance buildup under stress/heat....EXCEPT..

 

We are all aware, or CAN be, that Mazda addressed this very same issue via the addition of PTO cooling using the engine coolant system.

 

Simple, the Ford engineers have screwed the pouch.

[akirby]

Simple, I have absolutely no idea what I'm talking about.

 

Fixed it for ya.

[regal1976]

There doesn't seem to be any known fix for the stinking PTU problem. If you read all the post on the subject, you will see that some people had the seals changed, others had the PTU replace, others like me had the seals and the drive shaft replaced.

 

I think Ford is still in diagnostics mode which means they don't completely understand the whole problem therefore can't provide for a fix. Seems to me they are guessing at the fix by trying a variety of things.

 

Ford needs to state what the problem is and secondly what the fix is.

 

You can read more about this problem at www.smokinedge.com

 

 

Gary Smith

SMOKIN EDGE

 

OBVIOUSLY no fix and not resolved in 2008 Edge. VERY disappointed only had car 1 month and it's in the shop -- you guys are scaring me! The only loaner the dealer offers in the Focus - NOT A HAPPY CAMPER.

[regal1976]

what other issues, other than this one, should I watch out for???

[MrsWeidner]

Well, folks... add ME to the list! Thankfully, I read this forum because I TOLD my dealer what to look for... I had read this forum several months back. For the last 3 days my car reeked of burned oil/rubber smell. Took it in today, told him to check the PTU and sure enough, that's what was causing the issue! They replaced the seals only.... so I'm sure I'll be back based on the other experiences of others on this board! Thanks for all the great info... pretty sure my dealer should pay me to be his mechanic. LOL.

Oh, and this is on a 2008 Edge Limited AWD 42,000 miles. I've had it since April.

[Johnathan Hall]

Well just like many of you I have a 2007 Ford Edge SEL AWD. Great car other than this problem. It started in Sept of 2009 but no smell only a leak. Now for me it is a little more complex as I am in the US Air Force and I am based in Germany. The warranty is covered here at the local European Ford Garage, but it takes longer to get parts. So after about 30 days, $500 worth of rentals, and 4 visits to 2 different garages...The first garage said nothing was wrong. The second garage said there was a problem and replaced the seal kit twice then replace the entire PTU. Now a year later and I have both the odor and the leak(noticed it on the snow today). so now i must take it in to the German Ford Garage and hassle through the language barrier again to try and get my car fixed. it now has just under 40,000 miles and is just over 3 years old. thankfully it is still under the power train warranty!

[Mark DeLange]

Ok here is goes: I need to sign in and unload somewhere because I am done with Ford. I have an 08 for EDGE AWD that started to stink about three months ago after I had the drive train components serviced by a local shop not a Dealer. I took the car back to my service shop that had changed my PTU oil, they recommended that I take it to the best transmission shop in town so I did. The owner took me in the back room and showed me 2- 55 gallon drums full of PTU units from the Tarsus, Flex and Edge AWD vehicles. /This is what he said: The transfer case/PTU sits in a very harsh extremely high temp location next to the catalytic converter in all these cars and has no shield to keep the heat off the PTU. Every car that he had worked on needed a new PTU because the oil was gone out the seal or out the vent. He pulled my PTU out and split the case and said it was not damaged but was close to being trashed. Placed a new seal in the PTU drilled a drain hole and added a vent hose extending the vent up three ft. He also fabricated a heat shield . I really trust this guy because he created a solution to the original problem. He told me to off the car and get something else. I am going to take his advice and do that. I really love this car and it has performed for me in heavy show and many bad roads in the Sierra's. It has seen two ft of snow for 10 miles and never flinched. Ford will need to come up with a better solution and stop lying to there customers. If you have a warranty use it have it fixed and off the car. I hope that before people purchase these cars they read these posts.

[Waldo]

Ok here is goes: I need to sign in and unload somewhere because I am done with Ford. I have an 08 for EDGE AWD that started to stink about three months ago after I had the drive train components serviced by a local shop not a Dealer. I took the car back to my service shop that had changed my PTU oil, they recommended that I take it to the best transmission shop in town so I did. The owner took me in the back room and showed me 2- 55 gallon drums full of PTU units from the Tarsus, Flex and Edge AWD vehicles. /This is what he said: The transfer case/PTU sits in a very harsh extremely high temp location next to the catalytic converter in all these cars and has no shield to keep the heat off the PTU. Every car that he had worked on needed a new PTU because the oil was gone out the seal or out the vent. He pulled my PTU out and split the case and said it was not damaged but was close to being trashed. Placed a new seal in the PTU drilled a drain hole and added a vent hose extending the vent up three ft. He also fabricated a heat shield . I really trust this guy because he created a solution to the original problem. He told me to off the car and get something else. I am going to take his advice and do that. I really love this car and it has performed for me in heavy show and many bad roads in the Sierra's. It has seen two ft of snow for 10 miles and never flinched. Ford will need to come up with a better solution and stop lying to there customers. If you have a warranty use it have it fixed and off the car. I hope that before people purchase these cars they read these posts.

 

Ugh, your Edge was designed about 9 years ago, you don't think Ford's been working on it since then?

 

Did you also notice that this thread is almost 3.5 years old?

 

Besides, if your issues started after having a local shop replace fluid that Ford says not to replace, don't you think it's possible that it was the service that caused the problem, not a design issue from Ford? it would be pretty easy to overfill, underfill or use the wrong fluid.

Edited May 1, 2014 by Waldo

[Feirstein]

Based upon detailed information posted elsewhere on this forum I fixed my transfer case problem for about $150.00.

 

My mechanic drilled a hole in the bottom of the case. We drained out the old fluid (very little came out, 145,000 miles).

We cleaned the top of the case with solvent since it was covered in thickened grease/fluid.

We ran kerosene through the case 2 times, than we ran Mobil 1 gear oil through it twice.

it now does not drop grease on the floor and it works like new.

Don't know why Ford would not recommend this procedure.

Edited May 5, 2014 by Feirstein