Mitsubishi/Hyundai F4A41/42/51
Misassembly of the low/reverse and/or second-brake clutch packs in Mitsubishi’s F4A40 and 50 series transaxles can occur easily. Especially if you are the individual who answers phones, makes parts orders, road-tests vehicles, handles problems under the lift and rebuilds transmissions, all in a day’s work. And when a misassembly takes place, the transmission may slip through second, chatter in reverse, go to limp mode with a second-gear ratio code and/or a solenoid-performance code.
September 2004 Issue
Beginning with the 1999 model year, Isuzu NPR, GMC Forward Tiltmaster, Chevrolet Forward, Nissan UD and Mitsubishi Fuso trucks no longer use the JR403E Electromatic transmission.
These trucks now are equipped with the Aisin Seiki 450-43LE transmission (see Figure 1), a Toyota-designed transmission that is almost identical to a 1993-94 Toyota Land Cruiser A442F transmission.
There She Blows!
Lately on the phone lines, we’ve had a rash of calls concerning transmission fluid spewing out the filler tube on trucks equipped with the JR403E Electromatic transmission once the transmission reaches operating temperature.
Subarus Have Their Own Set of Problems
The four-speed automatic Subaru is a first cousin to the RE4RO1A, RE4RO3A and JR403, but the Subaru version of this transmission has not been plagued by the converter-clutch problems that have afflicted other members of its family. The Subaru was the only one to offer an all-wheel-drive option, which has allowed it to have its own set of problems.
New Venture Gear Transfer Cases
In the manual-transmission market, stick-shift transmissions make up roughly 20% of the vehicle population, with automatic transmissions grabbing the lion’s share of the market. The transfer-case market has exploded with the variety of SUVs and crossover vehicles being added to the market and the fact that whether the transmission is manual or automatic, a transfer case must be involved to obtain four-wheel drive.
An Optical Illusion
There is nothing more frustrating for any technician and/or shop owner than to encounter a late-model vehicle experiencing problems and have no diagnostic codes to go by. One well-experienced example of this would be with pre-1996 vehicles. Many different styles of electronic transmissions would not set a code for an inhibitor switch because there were no codes for the computer to produce. So when it would malfunction, it would leave the technician clueless as to the source of the problem.
Good Vibrations: 4T60-E Differential Problems
A customer comes into your shop in a GM vehicle with a 4T60-E transmission that’s making a lot of noise no matter what speed the car is going but is quiet as long as there’s no wheel movement, or possibly no movement at all. You do the basic diagnostics, pull the pan and discover that the pan is full of metal, and upon disassembly you find the differential parking-gear bearing is blown. Or, even worse, a unit you just repaired a couple of months ago comes back with one of these problems.
Advanced Clutch Diagnostics
Clutch replacement is a common shop repair that is a profitable and relatively simple job if you follow proper inspection and installation procedures. About 50% of all manual-transmission failures or wear-related problems begin with a worn or damaged clutch.
August 2004 Issue
Allison World Transmissions are fully computer-controlled transmissions that come in three truck models and four bus models. The model designations are AD, MD and HD, and each is rated for different gross vehicle weights (GVW).
Morning Sickness – Well, Sort Of
At ATSG we have received several calls on the 5R55N/W/S transmission in the new Lincoln LS, Jaguar, Ford Explorer or Mountaineer concerning a complaint of delayed or no engagement. The condition occurs most often during first morning startup, under extreme cold-temperature conditions, and the transmission may engage if the throttle is snapped wide open.
It’s an Inside Job
The 2003-and-up Audi A4 and the 2002-and-up A6 with a 1.8- or 3.0-liter engine use a continuously variable automatic transmission known as the Multitronic® 01J (see Figure 1) and also referred to as the VL300. The core of this article is not that this transmission is a CVT. The focus is on what’s inside the transmission other than the drive- and driven-pulley set.
July 2004 Issue
Issue Summary:
Before or after overhaul, vehicles equipped with the 4L30-E transmission may exhibit a binding sensation on take-off in Drive or on the 2-3 upshift.
Hyundai vehicles equipped with the F4A42/51 transaxle may come in with complaints of erratic and/or harsh shifting, third-gear failsafe and one or more codes for open or shorted solenoid circuits.
After overhaul, Mitsubishi vehicles equipped with F4A40 or F4A50 series transaxles may exhibit shuddering engagements or harsh upshifts.
Before or after overhaul, Mitsubishi vehicles equipped with F4A40 or F4A50 series transaxles may exhibit a flared or harsh upshift into third gear.
