How does a 4L80E Shift?
The 4L80E transmission may feature two speed sensors, one for turbine input speed and one for output speed. It uses the Input Speed Sensor to monitor input speeds to compare against engine speed and output Shaft Sensor speed, using this data to adjust shift speeds under instantly detectable conditions.
How many gears are in a 4L80E transmission?
It takes three planetary gear assemblies to make up the five different gears ratios in the 4L80E.
Can you manually shift a stock 4L80E?
The stock ECU will control the 80e just fine. If you want full manual you can also look into the Trango 4L80E-3. That kit uses a vacuum modulator to control pressure and manually shifts with the shift lever.
What are the problems with the 4L80E transmission?
No shift into OD under acceleration; OD will not hold under load and can hear or feel trans shift to OD when throttle is let off but slips into 3rd when throttle applied; sudden erratic lugging condition in lower gears when manually shifting: Bad news: this is going to involve a lot more time and money to fix this problem.
What to do if your 4L80E is stuck in 2 from 3?
P-R-N-D work, upshifts mostly work, no downshift into 1 from 2 or to 2 from 3, “stuck” in a certain gear: Pull out the wallet and grease pan. You have to replace the solenoids that control the 1-2 and 2-3 shifts, the “A” and “B” solenoids respectively (the 3-OD shift is not controlled via a solenoid…more on that later).
Are there any transmission problems with a 454SS?
As such, most of the 1991-1992 454SS trucks came with 4L80E transmissions that had faulty parts from the factory. Most of the problems are electronic in nature and are relatively easy, but expensive, to fix. This article deals with fixing your factory 4L80E to make it as durable and reliable as it should have come from the factory.
Why does my 4L80E not downshift to lower gear?
The problem with these are that the solenoid intake port has no screen, which means any debris floating around in the pan can get into the very small inlet hole and jam the solenoid open, forcing fluid flow, which prevents the plunger from sliding in the valve body and hence prevents a downshift to the next lower gear.