Where is the Transmission Control Module on a 4L80E?

The 4L80E Transmission system is equipped with a computer called the Transmission Control Module (TCM), located in the left/rear passenger seat compartment which interprets, ana-lyzes and records electronic signals from sensors and switches located on the engine, brake pedal, and transmission.

How much does a GM 4L80E automatic transmission weigh?

The transmission typically accepts a 6.3 quart fill. It features a dry weight of 254 lbs. and can weight up to ~268 lbs. full. Like earlier automatics, the 4L80 features one line pressure tap available for testing and diagnostic purposes.

Is the 4L80 transmission compatible with the CJ5?

The 4L80 is doubtless a very successful OEM transmission, and a terrific conversion transmission in the right Jeeps and situations. However, with its 26-1/4″ length, it is a longer transmission and is not compatible with short-wheelbase Jeeps such as the CJ5 in any scenario, or CJ7’s if they have a lot of suspension lift.

What is the RPO code for a GM 4L80 transmission?

The 4L80 nomenclature denotes that the transmission is a 4-Speed, Longitudinally mounted, and for 8000 lbs. vehicle weights. It’s RPO code is “MT1” and has been domestically manufactured in GM’s Ypsilanti and Willow Run plants.

What kind of transmission does a 4L80E have?

– The transmission is defaulted to second gear (4L80/85-E). – The transmission is defaulted to third gear (4L60/65-E). – The instrument cluster is inoperative.

Is the neutral safety switch on my 4L80E working?

Replaced the Neutral safety switch, nothing changed. Checked for voltage at the Ign.1 “O” fuse,and the pink wire at the trans. neutral safety switch. All tested good, battery voltage.

What causes OD on a 4L80 diesel?

Since your transmission has 200Ks on it the problem is likely that the valve sleeve bore has worn. When the Torque converter Solenoid strokes the piston the transmission fluid leaks past when hot. The hydraulic signal get so weak that it will no longer activate the control valve within the pump thus kicking in OD.

What’s the problem with the 4L80-E no overdrive?

The most common problem facing the 4L80-E NO OVERDRIVE and how to deal with it. Not open for further replies. If the problem is electrical then chances are you can troubleshoot the problem yourself. The torque converter has a torque converter clutch. It is this clutch that provides the mechanical coupling from the engine to the transmission.

What does DTC 79 on a 4L80 do?

It is the Transmission Fluid Temperature Sensor. DTC 79 is transmission fluid Overtemp. A defective temp sensor will prevent overdrive. Use a multimeter between pins L and M to check for resistance. The temperature is related to resistance.

What kind of transbrake does a 4L80E use?

It is a very quick acting transbrake. It works very well in full manual configuration. It has some special tuning considerations for use with a controller in an automatic shift situation. Our D3 transbrake allows for transbrake operation in any forward gear range. It requires transbrake activation for reverse.

Is there an upgrade option for the 4L80E?

We have several upgrade options for the various stages of 4L80E. We offer two different transbrakes. Both designs will work in a stock depth pan. Our D1 transbrake, also known as the Manual Low transbrake, allows normal reverse operation but requires the gear selector to be in the 1st or low gear position to operate.

What kind of tailhousing does a 4L80E use?

Mechanical speedometer tailhousing kits are available WITH transmission for this price. These include the tailhousing with new bushing, seal, o-ring, speedometer gears calibrated for your combo, and driven speedo housing.

How does a shift solenoid work on a 4L80E?

The 4L80E uses shift solenoids A and B to control upshifts and downshifts in all forward ranges. The solenoids are both powered with system voltage when the ignition is on. Ground is provided by the vehicle PCM in a specific sequence to control shift scheduling (figure 1).

What is the pulse rate on a MEGAshift 4L80E?

* The Pressure Control solenoid controls main line pressure, pulsed at 0-60% duty cycles at 293 Hz. There is a cleaning pulse (dither) every 10 seconds on this transmission (Early 4L80E).

What’s the difference between 4L80E and 4L60E output patterns?

The main difference between the 4L80E and the default 4L60e output pattern is the pattern for solB (output2) is ‘inverted’: The wiring inside the 4L80E transmission looks like this: The corresponding AMPseal connections for the control/sense functions are: In addition there are: On the GPIO, the connections are:

* The Pressure Control solenoid controls main line pressure, pulsed at 0-60% duty cycles at 293 Hz. There is a cleaning pulse (dither) every 10 seconds on this transmission (Early 4L80E).

Is there no upshifting on a 4L80E?

A while back I moved to the Rockies – drove 11 hours straight hauling probably 1000 pounds, no problems at all. Pulled out of the driveway the next day and BAM – no upshifting, high revs with no power, only manual shifting to R,N,D,2, and 1.

Is the input speed sensor on my 4L80E burnt out?

Figured my 4L80E was blown for sure, called a couple of transmission shops – $300 just to look at it, and probably they would recommend a rebuild/replace. Did some looking around and finally discovered that this exact situation – no upshifting but all manual gears available – could be a burned out input speed sensor.