4l60e trashed rear planet
08-10-2022, 01:48 PM
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Car: 92 Z28
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Re: 4l60e trashed rear planet
Have always had a harsh shifting 1 to 2nd. Almost like a lurch forward when 2nd is applied. Have rebuilt several 700r4 s but never an E. Heard about the PCS commanding a higher than normal pressure problem. Few valves in VB possibly going bad. Anyone ever had this issue. I believe maybe that may have caused the damage.
08-11-2022, 11:08 AM
#4
Re: 4l60e trashed rear planet
I've had several 4L60E's go bad- usually sunshell, I think one was planetary or pinions. Never rebuilt one myself.
Being an "E", pull the tune and compare to a stock file. Most of the parts and cars we're working on have had several PO's and I wouldn't be surprised if a PO or "tooner" performed some computer magic, shift kit, servos, any number of things that can cause a harsh 1/2 shift. To my knowledge, the PCM will command higher line pressure IF it's put into limp mode- otherwise it has to be tuned for it. I recall that you can turn up line pressure with a torx screw on the force motor in the early 4L60E's. Don't recall how long that trick extends through the years.
Being an "E", pull the tune and compare to a stock file. Most of the parts and cars we're working on have had several PO's and I wouldn't be surprised if a PO or "tooner" performed some computer magic, shift kit, servos, any number of things that can cause a harsh 1/2 shift. To my knowledge, the PCM will command higher line pressure IF it's put into limp mode- otherwise it has to be tuned for it. I recall that you can turn up line pressure with a torx screw on the force motor in the early 4L60E's. Don't recall how long that trick extends through the years.
08-12-2022, 01:01 AM
#5
Re: 4l60e trashed rear planet
If you've done 700's, you'll be good doing a 60e.
With harsh 1-2 shifts I would start by looking at the 1-2 accumulator for a broken spring or even worse, blocked by a builder.
With harsh 1-2 shifts I would start by looking at the 1-2 accumulator for a broken spring or even worse, blocked by a builder.
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HawkZ28 (08-13-2022)
08-12-2022, 12:25 PM
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Re: 4l60e trashed rear planet
08-13-2022, 08:13 PM
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Car: Resto-Mod 1987 IROC-Z Clone
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Re: 4l60e trashed rear planet
Sun Shell Failure prevents 2nd, 4th, and Reverse from operating.
The Transmission will start off normal, but will not shift out of 1st unless the Engine RPM is up there...
Only then will it Up-Shift, but into 3rd Gear (NO 2nd or 4th).
A Harsh 1-2 Shift will damage the Sun Shell in time.
The Transmission will start off normal, but will not shift out of 1st unless the Engine RPM is up there...
Only then will it Up-Shift, but into 3rd Gear (NO 2nd or 4th).
A Harsh 1-2 Shift will damage the Sun Shell in time.
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