Keep Those Trannies Rolling
Ford Fusion, Harsh 3-4 Shift after Rebuild
by Pete Huscher members.atra.com www.atra.com
I
n this issue of Keep Those Trannies Rolling, we’re going to look at a 2006 Ford Fusion equipped with the 5NR5 automatic transmission. This unit was experiencing harsh 3-4 shifts after a rebuild.
Beginning at the End
Our story begins at the end of the repair with a call to the ATRA Technical Hotline from Jeff Peacock of Peacock’s Transmissions in Cleburne, Texas. Jeff was working on a 2006 Ford Fusion equipped with Ford’s 5NR5 five-speed automatic transmission. It had harsh 3-4 shifts after a rebuild. Jeff worked through the problem, and wanted to share his solution with the rest of ATRA.
Erratic Shifts
The vehicle came into the shop with erratic shifts. After test driving the vehicle and inspecting the transmission, Jeff determined the transmission had an internal problem and would have to be removed, disassembled, and inspected. During disassembly and inspection, Jeff noticed the 2/4 band was burnt. He air-checked and inspected the 2/4 servo circuit and discovered the servo seemed to be working properly. He inspected the valve body for wear, knowing that these valve bodies have been known to experience premature wear. This valve body looked okay. Jeff went ahead and rebuilt the transmission.
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The Crew of Peacock Transmission
Harsh 3-4 Shift after Rebuild
After rebuilding and installing the transmission, Jeff took the car for a test drive. While driving, he noticed the transmission had harsh 3-4 shifts, but all other shifts seemed normal. He brought the vehicle back to the shop and checked the computer system for codes: There were none. He then installed a pressure gauge on the line pressure tap and checked the line pressure during the shifts. The line pressure was steady during each shift, so the harsh 3-4 shifts weren’t caused by excessive pressure. With no codes in the computer system and line pressure within specifications, Jeff knew he was heading back inside the transmission.
Shana Peacock Keeps it Running Smooth
Repeat 2/4 Band Failure
After removing and disassembling the transmission again, Jeff found the GEARS October/November 2010