Tranny/Vacuum modulation/PCM question
12-22-2005, 01:05 PM
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Tranny/Vacuum modulation/PCM question I just had my 4L60E fitted with TransGo's Vac Mod kit, which IIRC eliminates the PCMs control of line pressure. The tranny will upshift fine, but it slips in every gear. (Truck still at tranny shop). I also had the shop install an Edge 9.5" converter w/3000 stall. 2 questions:
Does the PCM have any other control over line pressure besides the EPC solenoid?
Will the higher stall (and smaller diameter converter) cause any issues that needs to be compensated for through tuning?
Does the PCM have any other control over line pressure besides the EPC solenoid?
Will the higher stall (and smaller diameter converter) cause any issues that needs to be compensated for through tuning?
12-22-2005, 01:27 PM
#2
Sounds liek something wrong with the vac mod install. Did it hold gears fine before? You should not have to change anything as fars tuning goes except for lockup on the converter as you might want it to lock a little later, and also the shift points but nothing that would cause the trans to slip.
12-22-2005, 01:35 PM
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[QUOTE=hellbents10]Sounds liek something wrong with the vac mod install. [QUOTE]
That was my first though as well. There also was the boost bypass valve to add to the fun. The tranny tech (20 years experience) and 2 other shop guys triple checked everything. I'm gonna stop by later today and take a personal look.
That was my first though as well. There also was the boost bypass valve to add to the fun. The tranny tech (20 years experience) and 2 other shop guys triple checked everything. I'm gonna stop by later today and take a personal look.
