Replacing the 41TE Transmission in a Chrysler 2.7 Engine

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Overview
I needed to change the torque converter on my car, but since this requires removing the entire transmission, I replaced it as well.
Of the major car jobs, this is the easiest because you simply unbolt the old transmission and bolt the new one on.
Getting to it though... that's another story.
Whenever you do a major job like this, it's good to replace other things that you're removing as part of the process. At high miles your struts could use replacement. Same with engine mounts or anything made of rubber. I will cover these separately later.
About Automatic Transmissions and Torque Converters
I recently got the OBD code 740 trouble code, which means that when the transmission tries to lock up the torque converter it did not notice an RPM drop. Let me explain.

An automatic transmission transfers power from the engine to the wheels through fluid coupling. It's as if the engine is one fan that is face-to-face with another fan connected to the wheels. When the engine fan blows air towards the wheels fan, it causes it to turn. But some energy is lost through air (oil, in the case of the transmission) so for example in order for the second fan to turn at 3000 rpm, the first one may need to be turn at 3200 or so.

Click images to enlarge
Automatic transmission fluid coupling fan analogy

A lockup converter is designed to regain this lost energy by coupling the wheels directly to the engine once the car gets to cruising speed. From the analogy above, suppose that once the first fan gets the second one upto speed we then link their axii directly to each other. Then to keep the second fan turning at the same 3000 rpm, the first one needs to slow down from 3200 to 3000 as well.

Automatic transmission fluid coupling lock-up converter

That's what the lock up mechanism does, it enables the engine to work more efficiently, saving fuel. Because this wasn't working as designed in my car, it would not pass smog.

I first replaced the transmission oil, treated the transmission with Bar's transmission repair, but nothing worked. The code would come right back. I finally took it to a shop that was doing complimentary diagnostics. They gave me a report on the pressure levels in the transmission and it was clear that the converter had to be replaced.

Raise the Car as High as Possible
To get started, use a good pair of stands and raise the car as high as possible. You need the clearance for the transmission to come off. Apply the parking brake and put a two-by-four behind the rear wheels.
Remove The Air Intake Ducts
Work your way from the top of the engine down:
  • Remove the Air filter container.
  • Pop the air duct from the air filter box
  • Remove the throttle body clamp

Dodge stratus remove air intake and throttle
Disconnect the Radiator Coolant Lines

The grime in this area indicates that the lines may have been leaking oil, but I'm not sure if this led to the demise of the converter.
Chrysler / Dodge remove transmission radiator lines
Disconnect Everything Connected to the Transmission
Disconnect solenoid connector, range sensor connector and speed sensor connectors.
Disconnect shift cable, dipstick tube and oxygen sensor harness.
Disconnect the ground cable near the rear cover / left wheel.
Chrysler remove electrical ground lines
Remove Wheels, Steering Knuckles and Axles

See links to these writeups:

Axle replacement
Strut replacement
Disconnect the Bell Housing
Support the engine and transmission with jacks.
Work your way top to bottom unfastening the transmission-to-engine bolts.
Remove Chrysler transmission upper bell house bolt
Remove Front and Rear Engine Bolts and Mounts
You still have those jacks in place, right? Locate the rear mount through bolt, unscrew it.
Remove Chrysler rear transmission mount bolt
Locate and remove the front mount throughbolt, front mount and front mount-to-engine bracket.
Remove Chrysler front mount
Remove the Starter
Remove the starter-to-transaxle bolts. Carefully remove the starter-to-battery cable bolt. Wrap the cable in a plastic bag to avoid shorting.
I didn't remove the other cable, I just tucked the starter away from the working area.

Remove Chrysler engine starter

Disconnect the Engine (flywheel) from the Transmission
Remove the flywheel dust shield.
Remove the four flywheel-to-torque converter bolts. First use a tire iron or similar tool to turn the flywheel and loosen bolts then remove them in a second pass.

Unfasten transmission flywheel bolts

Disconnect the Left (Driver-side) Engine Mount
Check the jacks.
Loosen the four bracket-to-mount bolts.
Remove the mount bracket but install back the chain attachment.
Remove Chrysler left transmission mount

Lower and Remove the Transmission
The transmission is ready to come off, but it will want to jam and snag on everything. I used cardboard between the flywheel and torque converter and lithium grease around the suspension crossmember.
I connected a chain to the chain loop at the left-engine bracket then put a two-by-four through the chain and the left strut tower to wiggle the transmission out.

Remove the Left Mount
Is the mount showing its age? If so, replace it.
New and torn engine mounts
Transmission off.
2.7 engine with transmission removed

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To Step 2 - Installation