4l60e shift quality concerns after swap
06-04-2013, 10:08 PM
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4l60e shift quality concerns after swap i have a 98 jeep wrangler that i swapped a 6.0 lq4 and matching 4l60/65e into from an 01 yukon denali xl
i was told the trans was just rebuilt before the driveline was pulled, but i didnt see a fresh convertor so who knows.
Tune was done by wayne at 150tunes.com/pirate4x4.com
I'm experiencing a long 1-2 shift at anything above 40-50%tps
downshifts are harsh and seem to engage softly, slip a bit, then re-engage and give a nice little thump when it hits the 3-2 shift.
any ideas on this? anything i can datalog and watch with my DashDaq or Tech2? low throttle shifts are great and in the 0.08-0.3 second range per the dashdaq, however when above half throttle, i'm getting 1.5sec shifts.
the tuner said he actually adds a bit more torque management into the tune with a 6.0/60e combo. so its supposed to be more than factory, is this maybe what i'm feeling?
Edit: Just read something about vac leaks causing bad trans performance. Engine load is 3-7% at idle, shouldn't this be 0%? I also have the hunting idle when going from D-P or R-P where idle will go from 450-600 a few times then settle at 540. Thinking i have a vac. leak.
i was told the trans was just rebuilt before the driveline was pulled, but i didnt see a fresh convertor so who knows.
Tune was done by wayne at 150tunes.com/pirate4x4.com
I'm experiencing a long 1-2 shift at anything above 40-50%tps
downshifts are harsh and seem to engage softly, slip a bit, then re-engage and give a nice little thump when it hits the 3-2 shift.
any ideas on this? anything i can datalog and watch with my DashDaq or Tech2? low throttle shifts are great and in the 0.08-0.3 second range per the dashdaq, however when above half throttle, i'm getting 1.5sec shifts.
the tuner said he actually adds a bit more torque management into the tune with a 6.0/60e combo. so its supposed to be more than factory, is this maybe what i'm feeling?
Edit: Just read something about vac leaks causing bad trans performance. Engine load is 3-7% at idle, shouldn't this be 0%? I also have the hunting idle when going from D-P or R-P where idle will go from 450-600 a few times then settle at 540. Thinking i have a vac. leak.
Last edited by dantj; 06-04-2013 at 10:17 PM.
06-05-2013, 11:20 AM
#2
Moderator
It sounds like the line pressure is not going up with throttle position. It is important that all engine sensors are working correctly, e.g. the VSS, TPS, MAP and MAF.
Your mention about engine load at idle suggests that the TPS might be off and this would dramatically affect trans operation. You need a scanner (or volt meter) that can measure the TPS voltage with the throttle closed. I don't remember the exact voltages, but it has to be within a range (perhaps .15 to .45V) or the computer thinks the TPS is not working. If off, the TPS has adjustment screws to get the idle voltage right.
Beyond that, I would recommend hooking up a trans pressure guage ($45 on ebay) and driving with it to see what the line pressure is at different throttle positions.
Also a quick test is to disconnect the MAF and see what effect if any that has. Just a warning that there is a slight chance that at WOT, a disconnect MAF combined with a bad tune could lead to an overly lean mixture and engine damage.
Your mention about engine load at idle suggests that the TPS might be off and this would dramatically affect trans operation. You need a scanner (or volt meter) that can measure the TPS voltage with the throttle closed. I don't remember the exact voltages, but it has to be within a range (perhaps .15 to .45V) or the computer thinks the TPS is not working. If off, the TPS has adjustment screws to get the idle voltage right.
Beyond that, I would recommend hooking up a trans pressure guage ($45 on ebay) and driving with it to see what the line pressure is at different throttle positions.
Also a quick test is to disconnect the MAF and see what effect if any that has. Just a warning that there is a slight chance that at WOT, a disconnect MAF combined with a bad tune could lead to an overly lean mixture and engine damage.