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The JF011E to the JF015E

Frequency of this popular transmission pushes shops to take on repairs
Thursday, July 30, 2015 - 07:00
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The JF011E (as it is called in Dodge and Jeep applications), is a JATCO-made CVT, which is also referred to as the RE0F10A in Nissan and the F1C1A in Mitsubishi (Figure 1). With this transmission having such a presence on the road today, it comes as no surprise that many shops have chosen to take on repairing this simple transmission.

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Figure 1
Figure 2

Unlike the Honda CVT that doesn’t use a torque converter, this transmission does (see Tackling CVTs, July 2015). As a result, this transmission uses a forward and reverse clutch in front of the pulley assembly rather than a start clutch between the pulleys and the differential.

I bring this up in preparation to introduce the replacement CVT for the JF011E simply called the CVT-7 or, traditionally you can call it the JF015E/RE0F11A/FICJB transmission, depending on the application.

This CVT-7 transmission still uses a torque converter, but it has a low clutch, high clutch and a reverse clutch assembly located between the pulleys and the differential; much like the Start Clutch in the Honda CVT. It is quite an interesting CVT and a very nice one to work on. But before we get to this new transmission, let’s cover a little about how the JF011E works and some of the problems the shops are seeing.

With this unit having a torque converter, along with a forward and reverse clutch in front of the pulley assemblies, there is no need to release a clutch when coming to a complete stop. The clutches simply provide forward or reverse direction through a planetary while the pulleys provide the continuously variable ratios. The torque converter operates in a conventional way meaning that as a fluid coupling, when at a stop in gear, the engine will not stall. During certain driving conditions, a clutch inside the converter will apply, providing a direct power link from the engine to the transmission. This means converter-related diagnostics will be similar when compared to typical automatic transmissions.

One issue that is common with this style of CVT is a delayed engagement into gear. (This was briefly mentioned in Can it be fixed? May 2015.) In it was a shop’s experience with a 2007 Nissan Altima. It had originally come in for one problem, which once resolved brought their attention to a 2 to 3 second delayed engagement into reverse and drive. Nissan has a bulletin stating that this is normal (NTB10-147). If the delay was much longer, they did have some TCMs that required re-programming to resolve the problem.  

One of the solenoids on the valve body is called the Lock-Up Select Solenoid (#4 in Figures 2 and 3: two different style valve bodies are shown -- Nissan/Mitsubishi and Dodge/Jeep). This solenoid controls the positioning of the Select “Switching” Valve in the valve body (#4 in Figure 4). By doing so, this solenoid controls two different functions. During drive and reverse engagement, this solenoid will place the “switching” valve in a position where it will direct pressure to the Select “Control” Valve (#5 in Figure 4). This “control” valve will reduce line pressure going to the Forward Clutch or Reverse Clutch for a smooth gear engagement. The Lock-up Select Solenoid can then position the “switching” valve where pressure is directed to the Torque Converter Lock-up Control Valve (#3 in Figure 4) for torque converter clutch apply control.

FIgure 3 Figure 4
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