That is a symptom the transmission has failed.
SOURCE: Rebuilt the Trans.(4L60E) in my
did you do the rebuild or did a shop do it? it sounds like the clutches werernt done properly. if the reverse is out the other gears will go out too if driven too far in that condition,
SOURCE: no reverse after rebuild on 4L60E Transmission from 1995 GMC Sono
There isn't a modulator on this trans as it is electronic
You can have first gear going forwrd but no reverse. It is possible. The low/ reverse clutch isn't needed to go forward.
SOURCE: 4l60e slips in 3rd and 4th
There are to many things that can cause this problem, best thing to is go get the ECM scanned for DTC codes at a transmission shop or Auto zone or Parts Source since they scan for free.
The ECM should have DTC code in it's memory on how the transmission is Performing and have the Transmission line tested for Fluid pressure.
Good luck and hope this helps. Oh and also ways check with more then on transmission shop if there tell you that you need a new Transmission,
It could be a simple as the transmission filter falling off causing the lost of transmission fluid pressure. Check the transmission fluid too.
SOURCE: reset code trailer towing may set code gm 4l60E
Diagnostic trouble code P1870 (Transmission Component Slippage) is a
General Motors-specific code whose set parameters are determined by
transmission type and engine size. The PCM monitors and compares engine
speed to vehicle speed after the converter clutch has been commanded ON
in either high gear or Overdrive. Should the expected rpm ratio exceed
predetermined parameters, DTC 1870 sets. And upon doing so, the PCM
elevates the transmission main line pressure and stops converter clutch
apply.
Once the vehicle has made it to a cruise state, the PCM then begins to
monitor the vehicle's cruise ratio. If at some point the transmission
begins to slip, P1870 sets and line pressure is elevated in an attempt
to stop any further slippage and prevent further damage. This would
explain why DTC 1870 Ls often accompanied by a complaint of a hard 1-2 up shift.
When this code sets, it could have any number of causes, ranging from
the sump running low of fluid to a malfunctioning torque converter.
Take a GM 4L60-E transmission, for example. When it's in Overdrive, the
forward clutch and the 3-4 clutches are applied, as well as the 2-4
band. Now add the converter clutch. This is what the PCM monitors at
cruise. If the ratio breaks away, the cause could be any of three
components, the hydraulics that operate them or the electronics that
control them. Fortunately, experience has shown that in most cases, the
cause can be traced to some form of converter clutch failure as a
result of valve body concerns. With GMs 4L80-E transmission, this code
has usually been the result of a cracked converter clutch piston.
Put a line pressure gauge ($55 shipped on Ebay, or visit a local trans
shop) on the pressure test port and go for a drive to verify proper
line pressure. Base pressure at idle in P,N,OD should be around 70psi
and around 140psi in R. Max line pressure should be at least 190psi at
WOT in 1st or 2nd, 225psi is optimum. If base pressure is low, trans or
pump is worn out. If max pressure is low, check EPC solenoid. If
reverse is slow to engage, and line pressure does not come up to at
least 130psi in reverse, replace the boost valve with a Transgo 0.049" - 0.500"
boost valve (easy fix in pan), and replace the servo with an upgrade servo from a Corvette 4L60E. This will give you a more firm shift and address the DTC 1870 which is common to a weaken Boost valve or faulty EPC valve.
SOURCE: 1994 chevrolet Silverado 4x4 with the transmission slipping
It will work but you will have to modify the crossmember and driveshaft and the computer. The 4l60e is an easy trans to recondition
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reverse works fine but no forward drive
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