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Soft shifts after pt 4000

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Old 12-02-2009, 07:53 PM
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Default Soft shifts after pt 4000

Before the pt 4000 shifts were pretty firm, but after the shifts seem much softer. The trans is stock, so should I just increase line pressure or install a shift kit.
Old 12-02-2009, 07:56 PM
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A shift lit would be the best move IMO however bear in mind the shifts are not in and of themselves softer . They are exactly the same and they were before you installed the converter, However the converter due to there inherent slip acts alot like a shock absorber giving the impression or feel of a softer shift when really nothing has changed from the trans perspective.
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Old 12-02-2009, 07:58 PM
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The converter just decouples the crank / flywheel
mass from the driveline and softens the feel of it.
There's no need to do anything, unless you really
enjoy the sensation of banging the driveline every
shift.

Though the trans settings probably could use some
work, if stock.

But you won't gain anything by trying to make the
shift sensation "harder".
Old 12-02-2009, 08:10 PM
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Originally Posted by jimmyblue
The converter just decouples the crank / flywheel
mass from the driveline and softens the feel of it.
There's no need to do anything, unless you really
enjoy the sensation of banging the driveline every
shift.

Though the trans settings probably could use some
work, if stock.

But you won't gain anything by trying to make the
shift sensation "harder".
Actually the line pressure was reduced because it shifted too hard. I don't like to have a neck snapping shift, but in my other vehicles they were still firm after I installed a looser converter. I just want to make sure that the temps don't rise due to a soft lazy shift. The converter does enough of that all by itself.
Old 12-03-2009, 09:55 AM
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I had the same issue with mine, then i had the trans rebuilt and it was firm again (not as firm as before). I have 3 spacers in the 2-4 accumulator from the transgo HD2 kit. Before the stall, it would chirp on a 1/4 throttle shift, now it only chirps the tires on a WOT shift.
Old 12-03-2009, 10:11 AM
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Why was it shifting firm before? Do you have a shift kit installed? A stock trans with stock programing should shift like, well, stock. Maybe you have a partial blockage in your cooler or lines. Stalled autos shift soft, or rather feel that way. As performa built stated, the shift is actually unchanged.
Old 12-03-2009, 01:29 PM
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The shift still happens the same, you just don't feel it. I have a shift kit with my PT4000 and it still doesn't feel like it shifts during part throttle.
Old 12-03-2009, 08:01 PM
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I know it would shift soft at part throttle,but wasn't expecting such a weak slow shift at WOT. I now have a check engine light, and from past experience with loose converters it was always a shift solinoid. The thing is that before with a shift solinoid code the trans would go into limp mode and I would have to turn it off then restart to get all gears back. I smelled the fluid tonight and it seems a little burnt. It was 1 1/2 qts low after the install yesterday, and I did hammer on it a little after the install. Guess there was air in the lines after installation that caused a false measurement on the dipstick.
Old 12-03-2009, 08:02 PM
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Originally Posted by 01ssreda4
Why was it shifting firm before? Do you have a shift kit installed? A stock trans with stock programing should shift like, well, stock. Maybe you have a partial blockage in your cooler or lines. Stalled autos shift soft, or rather feel that way. As performa built stated, the shift is actually unchanged.
Shifted firm by changing shift times and pressure.
Old 12-03-2009, 08:05 PM
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WOT should feel about the same. You're right that a solenoid code would keep it from using all the gears or lockup. Might want to see that code it is.




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