4l60e 3-2 downshift flare
4l60e 3-2 downshift flare I got my trans put back together after blowing out the snap ring teeth on the input drum. Now its in my RCSB Sierra. I used Dana's road race 3-4 clutch setup and his modified transgo shift kit. I'm running a vigilante 3000 rpm stall. It shifts very well through all of the gears at part throttle and at WOT but it flares up during a 3-2 downshift. It makes it feel like a very hard shift. It never feels like its slipping, just RPMs rise and it bangs into 2nd. I thought it was trying to go into 1st the first couple of time it did it. Obviously this could be any number of things but is it most likely a valve issue? What can I do to try to address this before it gets worse? I assume that during the shift the 3-4 clutches are releasing faster than the band is engaging. My servo travel is right at .075" and the clutch clearance is right around .030". I hope I can fix the downshift without changing the upshift since the upshift is so good.
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As you know, the valve body has a 3-2 downshift solenoid which controls the speed of the downshift based on throttle position. It is a PWM solenoid controlled by the PCM. There is also a 3-2 downshift valve which has a spring. As I understand it, the balance between the spring and the 3-2 solenoid duty-cycle control the speed of the downshift. The HD2 kit simply replaces the stock spring with a "solid" spring to force maximum 3-2 downshifts. This is Step 1 on Page 2 of the HD2 instructions.
So, do you have the HD2 spring installed here?
Beyond that, you should ask Dana for assistance.
So, do you have the HD2 spring installed here?
Beyond that, you should ask Dana for assistance.
Actually, I didn't know that there was a solenoid just for the 3-2 shift and had no idea that there was pwm control of any of the shift speeds. I guess I'm still very ignorant about how this thing works. I did install the 3-2 valve spring. I wonder if I can control the pulse width in the tune. I need to look into that.
