Materials needed: Linked products provided for reference.
- 0.35 L (12 oz) 75W-140
- 3/8” rachet
- 3/8” torque wrench
- 6mm hex bit socket
- Oil catch pan
- Brake cleaner
- WD-40 penetrant
- Rags or towels
- Gloves and pumice soap
- Oil hand pump
- Spare oil container
The 2001-2007 Ford Escape Power Transfer Unit (PTU) (aka transfer case) is a high rate of failure powertrain component for the 1st generation Ford Escape generation. The PTU is bolted onto the right side of the transmission and transfers drive power to the rear axel via the driveshaft. It is passively air cooled and separated from multiple high temperature components by a metal heat shield. Surrounding hot parts include the engine, transmission, and exhaust.
My Ford Escape’s PTU blew a hole at 160k miles and was replaced with a salvage part for about $1700 in 2017. The salvage PTU needed replacement at 190k in 2020 which cost about $1500. This time it was replaced with a remanufactured PTU. In both cases, the original and salvage PTUs had metal pieces broken off and making a high pitched clinking/tinging sound the months leading up to failure or diagnosis by an autoshop. This sound that is easier to hear at low speed with the windows down is presumably from the loose parts spinning around in the PTU.
A couple of existing videos on the PTU do a good job of explaining the flaw in the PTU design (no active cooling, runs too hot, filled for life). They all recommend changing the PTU fluid but the descriptions of doing the flush and fill might be not clear so I took some pictures when changing my 2007 Ford Escape Hybrid PTU fluid for preventative maintenance.
Proceed at your own risk! You are recommended to go to a certified dealer to service your vehicle.
- Secure the vehicle on level ground with a lift or equivalent jack stands. This is important for filling it with fluid to the correct level.
- Place an oil catch pan under the PTU fill hole to catch any spillage.
- Remove the PTU fill plug (3/8” rachet).
- There should not be any overfilled fluid spilling out . The PTU may burn oil due to running on light oil at a high temperature. In my case, the fluid was slightly low.
- Reposition the oil catch pan under the PTU drain hole.
- Remove the PTU drain plug (6 mm hex bit) and let the old fluid drain.
You need to use a low profile 6 mm hex bit to loosen the drain plug. The vehicle subframe is directly across from the drain plug and most rachet hex bits will be too long to fit in that space. I used a 6 mm hex L shaped key (allen wrench key) to loosen the drain plug as seen in the above picture. The drain plug should only be tightened to 10 lb-ft.
- Pump some new 75W-140 into the open fill hole to flush any remaining dirty fluid out of the PTU until the fluid runs clean.
The old 190k remanufactured PTU fluid came out as a opaque, dark gray color. The new 75W-140 fluid is a clear light yellow color. There was definitely tiny metal pieces in the drained oil.
- Clean the fill and drain plugs of metal build up.
- Wrap the threads in teflon sealant tape.
- Tighten the drain plug to 10 lb-ft.
- Pump 0.35 liters (12 oz) of 75W-140 gear oil into the fill hole. The new fluid should spill out of the fill hole when the PTU is filled to capacity.
- Tighten fill plug to 25 lb-ft.
Driving the 2007 Ford Escape Hybrid’s acceleration power felt more immediate and firm after replacing the PTU fluid. My fuel economy actually decreased after the PTU fluid change so this may be due to increased friction or variation in gear oil that I used.