I recently had the pleasure of dealing with a 2010 6R140 with a 2-3 flare that became worse as the temperature increased. Once the problem is identified, I normally look for any “quick” fixes first. Most days, saving time is saving money, and there just happened to be a bulletin from Ford addressing this issue. Unfortunately, like most things, nothing is a guaranteed fix, as many problems can have multiple causes.
After discussing the history of the vehicle with the customer, I found out they also knew of the Ford bulletin, and had another shop install solenoids and update the software. But to their dismay, they still had the same problem. The shop was not sure what to do next, so they brought it to me.
By definition, a flare on a shift is when the releasing friction and applying friction elements are both off (or not holding) for a brief moment. This can be caused by excessive torque, inadequate pressure applying the friction elements, or damage to the friction element or surface it holds when applied.
Possible causes of a 2-3 flare:
- Poor line pressure rise
- Leak in the circuit
- Valve body wear
- Friction material damage
- Solenoid mechanical malfunction
- Computer control of solenoids
I used my scan tool to verify the current software had been installed correctly. After verifying the software version, I switched the scan tool over to the data stream to monitor line pressure command. If I would have seen any abnormalities, I would have checked engine data for a possible cause of poor line pressure command.
On this vehicle, everything looked good in the data stream, my next step was to hook up a pressure gauge to confirm the transmission’s pressure is responding as commanded. If it wasn’t, I would have hooked an amp clamp to the wire for the pressure control solenoid to see if the computer was commanding the solenoid correctly. In this case, I was able to skip that step since the pressure was responding correctly.
Next, we dropped the pan. The fluid was in good condition and the solenoids had been changed (figure 1). With the new solenoids, good pressure response, and updated software, the list of possible causes was getting shorter. The cause has been narrowed down to a leak in the circuit, friction damage or valve body wear.
We removed the valve body, and air checked the circuit (figure 2). Surprisingly, with the extensive amount of miles this vehicle had, it air checked well at 35 PSI, and we did not hear any significant leaks at full shop air pressure.
In the valve body, there are two valves involved in the operation of the direct clutches, a latch valve (figure 3) and regulator valve (figure 4). Time to break out the vacuum test equipment, and start checking for worn bores. Upon checking the direct clutch regulator valve, we found an excessive amount of wear. Vacuum should have been 18 or higher, this one was around 12. I proceeded to check the other valves and found several below acceptable tolerances. At this point, it would be cheaper to replace the valve body than it would be to repair it.
Though we had identified the cause of the problem, we still have not confirmed if the friction material was damaged. The only way to do that will involve the removal of the transmission. If the fluid had been burnt or had an odor to it, I would have recommended the removal of the transmission before we ever dropped the pan. At this point, we contacted the customer, informed them of our findings and the possibility there might be more damage inside the transmission. We presented them the cost of rebuild or replacing the valve body, stating the valve body is damaged, and it would have to be replaced either way, and left the decision to them.
The customer decided to replace the valve body. We installed it, took it on a long test drive, and no more 2-3 flare. The customer saved money, and with their vehicle working, they couldn’t be happier. And our reputation in their eyes was golden.
The “quick” fixes are not always the way to go, but always a good idea to look into, as they can sometimes give you direction to the common problems. However, taking the time to do the diagnostics, can often keep the cost of the repairs down, and keep them from ending up back on the bench.
