sarsfield Posted April 5, 2023 Report Share Posted April 5, 2023 is it true that Ford has put in cooling on PTU's beginning in 2021? Quote Link to comment Share on other sites More sharing options...
dabangsta Posted April 5, 2023 Report Share Posted April 5, 2023 Seems like the ST got it in 2019, and in some cases (I think there is a hot weather group that is available in certain locales) earlier Edges with the 2.7 (Sport and ST) had it as well. Quote Link to comment Share on other sites More sharing options...
txaggie Posted April 5, 2023 Report Share Posted April 5, 2023 6 hours ago, dabangsta said: Seems like the ST got it in 2019, and in some cases (I think there is a hot weather group that is available in certain locales) earlier Edges with the 2.7 (Sport and ST) had it as well. Yes, my 2019 ST has cooling into the PTU. Quote Link to comment Share on other sites More sharing options...
kruzr1 Posted April 6, 2023 Report Share Posted April 6, 2023 I have a friend with a 2021 ST and he says it does not have the external cooling on the PTU. I have a 2019 ST and it definitely does. Did Ford delete this? Quote Link to comment Share on other sites More sharing options...
akirby Posted April 6, 2023 Report Share Posted April 6, 2023 I think they changed to the new PTU for 2020 that disconnects completely so the added cooling may not be needed. Quote Link to comment Share on other sites More sharing options...
dabangsta Posted April 6, 2023 Report Share Posted April 6, 2023 2019+ got AWD disconnect for all models (2.0 or 2.7 powered). 2 Quote Link to comment Share on other sites More sharing options...
Haz Posted April 6, 2023 Report Share Posted April 6, 2023 From the 2019 Edge Workshop Manual... Power Transfer Unit (PTU) Description The Power Transfer Unit (PTU) is a gearbox that attaches to the transmission. The PTU directs power from the transmission differential case through a dog clutch to a hypoid ring gear. A hypoid pinion gear is meshed to the ring gear and splined to the output flange. A dog clutch is used to transfer drive torque from the input shaft to the ring gear. When the dog clutch is released, no torque is transferred through the ring gear and pinion to the rear driveshaft. When the dog clutch is engaged, normal AWD function is achieved by directing torque to the rear wheels as needed to prevent or control wheel slip and improve handling There are two different models of the PTU. The low torque PTU is paired with the 8F35, 8F40, and MMT6 transmissions. The high torque PTU is paired with the 8F57 transmission. The low torque and high torque PTUs are similar in design and operation. Power Transfer Unit (PTU) Operation The PTU has four (4) distinct modes of operation: Connected, Connecting, Disconnected, and Disconnecting. Each mode is commanded by the AWD module. The PTU contains a reversible DC motor and two hall effect position sensors. The motor moves the shift fork which connects or disconnects the dog clutch collar. PTU Position sensor A monitors the position of the actuator cam. PTU Position sensor B monitors the position of the shift fork. Some PTU models are equipped with an oil temperature sensor. Connected Mode Connected Mode is the default mode for the PTU. The AWD module will command Connected mode at the beginning of each key cycle. In connected mode, the fork and dog clutch collar are positioned towards the RH side of the PTU. The dog clutch is engaged. The driveshaft is rotating at an overdrive ratio compared to the front axle shafts. Torque is available at the RDU. Connecting Mode To connect the PTU, the two halves of the Dog clutch must be within 40 RPM of each other. The AWD module calculates the speed differential based on transmission OSS, RDU Driveshaft Speed, and PTU gear ratio. The actuator motor will energize and rotate the gear reduction drive and the actuator cam against the actuator fork. When the dog clutch teeth line up, the cam pushes the actuator fork into position and the clutch engages. It can take approximately 100 - 150ms for the dog clutch to engage after the command is sent. Disconnected Mode The AWD module will command disconnected mode based on vehicle conditions. The purpose of the disconnected mode is to reduce drag losses from spinning the driveshaft when conditions indicate AWD will probably not be needed in the near future. In disconnected mode, the fork and dog clutch collar are positioned towards the LH or transmission side of the PTU. The dog clutch is disengaged. Disconnecting Mode To disengage the PTU, no torque can be routed through the dog clutch. That is, the RDU must be completely disengaged. Depending on vehicle conditions, the AWD module may keep the PTU engaged for the remainder of the key cycle. The actuator motor will energize and rotate the gear reduction drive and pull the actuator cam away from the actuator fork. When the dog clutch collar has moved far enough to the LH or transmission side, the dog clutch teeth disengage. Good luck! 6 Quote Link to comment Share on other sites More sharing options...
Cerberus Posted April 10, 2023 Report Share Posted April 10, 2023 (edited) On the subject of PTU temperature.. I took a therapeutic ride through the dragon today with my OBDlink adapter in and the app running to monitor data afterwards. in the attached pic, you'll see the PTU temp peaked at almost 270°F, and actually possibly higher since if the measured temp exceeds the range of the virtual gauge, it stops at the limit of the display. I am 95% sure that the heat at the PTU, at least in this instance, is from heat soak off the rear turbo. Ambient temp was around 70. Head temp got over 240 even though coolant never got over 205 (170 thermostat installed) Amyway, point being, i wish mine had a cooling feature.. Edited April 10, 2023 by Cerberus 3 Quote Link to comment Share on other sites More sharing options...
Haz Posted April 10, 2023 Report Share Posted April 10, 2023 A few PTU-related sections from the 2019 Edge Workshop Manual... Document download links> Power Transfer Unit Cooler - Vehicles With Power Transfer Unit Oil-to-Coolant Cooler - Removal and Installation - 2019 Edge Workshop Manual.pdf Power Transfer Unit Coolant Pump - Removal and Installation - 2019 Edge Workshop Manual.pdf Oil Temperature Sensor - Removal and Installation - 2019 Edge Workshop Manual.pdf Power Transfer Unit - Description and Operation - 2019 Edge Workshop Manual.pdf Power Transfer Unit Actuator Motor - Removal and Installation - 2019 Edge Workshop Manual.pdf Good luck! 3 Quote Link to comment Share on other sites More sharing options...
handfiler Posted April 11, 2023 Report Share Posted April 11, 2023 3 hours ago, Cerberus said: On the subject of PTU temperature.. I took a therapeutic ride through the dragon today with my OBDlink adapter in and the app running to monitor data afterwards. in the attached pic, you'll see the PTU temp peaked at almost 270°F, and actually possibly higher since if the measured temp exceeds the range of the virtual gauge, it stops at the limit of the display. I am 95% sure that the heat at the PTU, at least in this instance, is from heat soak off the rear turbo. Ambient temp was around 70. Head temp got over 240 even though coolant never got over 205 (170 thermostat installed) Amyway, point being, i wish mine had a cooling feature.. Yikes! These PTU's have way too small of an oil capacity. 3 Quote Link to comment Share on other sites More sharing options...
Cerberus Posted April 11, 2023 Report Share Posted April 11, 2023 I should point out, my edge is a 2016, and does the power clutching at the RDU if I'm not mistaken, so a unit swap would not work for me to add cooling. I've toyed with the idea of s turbo blanket and wrapping the rear pipe but not done anything yet. I am running the Redline lightweight shockproof fluid in the PTU so I tried to find the service temp range spec but found nothing on that. 1 Quote Link to comment Share on other sites More sharing options...
saile888 Posted April 27, 2023 Report Share Posted April 27, 2023 Hi, if you do let us know if it works Quote Link to comment Share on other sites More sharing options...
STBEAST Posted January 22 Report Share Posted January 22 I know I'm a bit late to this post, but it's kind of interesting how they are cooling the ptu. Correct me if I am wrong, please. They tap into the cooling output hose on the radiator and use an electric motor to circulate it through the ptu cooler and then it returns back to the radiator hose?? Quote Link to comment Share on other sites More sharing options...
TourGuide Posted January 22 Report Share Posted January 22 Yes - it is all plumbed through the radiator - so it should all (most likely) be run by the same circulation pump. This is a system they have implemented in really hot climates. The design in general has some significant weaknesses - one of which is oil capacity - and THAT will get no amount of improvement as it exists without increasing the reservoir. 1 Quote Link to comment Share on other sites More sharing options...
STBEAST Posted January 28 Report Share Posted January 28 Kind of interesting find. I drove around for a while I parked, shut the engine off and climbed went under the vehicle. I verified my 2024 still had the liquid cooled ptu. Man that thing was hot! The (electric) ptu coolant circulation pump was still running. Car was off. It ran for about 2 minutes then shut off. Any idea why it would keep running to circulate coolant through the ptu after shutdown?? As should be expected, I could not touch anything, it was so hot. The casing of the ptu would have burned me. Quote Link to comment Share on other sites More sharing options...
Cerberus Posted January 29 Report Share Posted January 29 1 hour ago, STBEAST said: Any idea why it would keep running to circulate coolant through the ptu after shutdown?? As should be expected, I could not touch anything, it was so hot. The casing of the ptu would have burned me. It is a common phenomenon that the generated heat in an engine will cause coolant temperatures to briefly climb after shut down. Given the proximity to the rear turbo and Catalytic converter, I expect the same type of thing would happen in the PTU, especially since the cessation of airflow after shut down. In my data logging on my 16 sport, I've seen PTU fluid temperatures north of 275°F, so the extra coolant circulation time is likely intended to offload a little more heat without excessive load on the battery reserve power. It's possible that the computer uses a temperature measurement to determine whether or not to run the pump, or for how long. 1 Quote Link to comment Share on other sites More sharing options...
TourGuide Posted January 29 Report Share Posted January 29 Hmm - Looking more closely at the documents Haz provided about the system - it seems there is a separate circulation pump for the ptu cooler - as there is a service procedure document for the replacement. It is plumbed through the radiator though - as I had referenced that myself earlier. I know there will be disagreement on this forum about it - but given the operating conditions - the only ways I can see to increase the reliability of this system would be - add a drain plug to facilitate a proper spill and fill - wrap the cat and use a turbo blanket to reduce the heat soak - and use a better (and here is the controversy) fluid - such as the lightweight shockproof stuff from red line. It is really THE fatal flaw for some iterations of this setup that a drain plug is missing. In those cases the service procedure is insane - and I am not talking about the jobber solution of evacuate with a pump and refill - that is a less than ideal service. 1 Quote Link to comment Share on other sites More sharing options...
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