Diagnosing the infamous GM 8L45, 8L90 3-4 neutral
Today we are examining what we’ll call a “Twilight Zone” transmission complaint: an issue that appears out of nowhere while performing a small, insignificant repair and initially makes little sense. The 8L45 and 8L90 3-4 Neutral condition, which has been baffling many shops/techs, is one such complaint. Problem: 3-4 Shift is Neutral after installing a
The ins and outs of the Hydraulic Selectable One-Way Clutch
A Hydraulic Selectable One-Way Clutch (SOWC) is used in GM’s 9T50 (figure 1, above) and Ford’s 8F35 transmission (figure 2, below). Its function and design are quite clever. The center plate inside this selectable one-way clutch lugs to the Overdrive Carrier. On the top side of this center plate are spring-loaded struts. Integral to the
TF80SC Gen 1 2-3 flared shift
The complaint A 2005 Volvo XC90 equipped with the TF80SC Gen 1 transmission has a complaint of a 2-3 flared shift. During the overhaul process a brand-new valve body from the dealer was installed, only to find on the initial road test that a 2-3 flared shift still existed. The adaption procedures were performed but
Mazda FW6A-EL stored pressure switch codes
The complaint A Mazda with the “Sky Active” FW6A-EL transmission has its Check Engine and A/T Warning lights illuminated, with the following trouble codes stored in TCM memory: P0842 “Oil Pressure Switch #1 (pressure switch B) Stuck On.” P0847 “Oil Pressure Switch #2 (pressure switch A) Stuck On.” P0872 “Oil Pressure Switch #3 (pressure switch
Honda Ridgeline bind up in reverse, forward in neutral
The complaint A 2006 Honda Ridgeline equipped with the BJFA Transmission has a complaint of a bind up in reverse and moves forward in neutral after overhaul. The truck would roll freely with the engine off and the transmission in neutral. Since this complaint occurred after overhaul, the technician thought that a clutch was mechanically
Common problems with uncommon solutions: 6L45 no-move or slipping forward
A 2010 3.0L Cadillac AWD CTS using a 6L45 transmission comes into the shop with a no-forward complaint. This particular vehicle is known for having the output shaft suffer from fretting, in which the output shaft to transfer case input shaft spline will strip and cause a no-move (figures 1 and 2). Sometimes, due to
No forced throttle downshifts
Twenty-five years ago, Chrysler introduced a 0.187-in. (4.77mm) steel, #10 check ball (figure 1, above) in the 42RE valve body which continued to be used throughout the entire RE series of transmissions (42, 44, 46, 47 and 48RE) as they were launched. This small check ball is quite active, having several functions during the course
Troubleshooting Ford 6F35 torque converter one-way clutch failure
It is Friday afternoon at Cooter’s Transmission, and the last of the day’s jobs are being wrapped up. Everyone is getting ready for spirits and good food at Buster’s Pub. A Ford 6F35 from a 2015 Ford Explorer rebuilt earlier in the week is installed, and something is not right. John, the installer, puts it
Shift adaptation issues: Potential causes of a 2-3 shift bump
For shift adaptations to perform adequately, all required inputs must be functional. Of course, the solenoids and transmission components must also be functional. The type of inputs required for shift adaptations to function as designed will have some variations based on year, make and model. For example, when Chrysler pioneered their 41TE clutch to clutch
A needle in a haystack: Finding and diagnosing intermittent problems
A customer brought in a 2013 Ram 3500 6.7L Diesel with the following issues: a CEL, a transmission temperature display on the instrument cluster reading incorrectly, and harsh shifting that would go into limp mode. This customer informed us that he just took delivery of the truck from a Dodge dealership. The dealership was aware of
Fixing JF011E primary pulley pressure sensor issues
A 2.4L Dodge Caliper using a JF011E CVT2 transmission developed a problem with the Primary Pulley Pressure sensor. A low circuit error code P0842 was pulled from the TCM. The sensor ground and 5-volt wiring circuits were checked and verified as good. The signal wire was then inspected and was also verified as good. There
A ghost in your vehicle: Troubleshooting errant voltage from Chrysler TIPM
Many of you may have already experienced various shortcomings from Chrysler’s Totally Integrated Power Module (TIPM). The TIPM contains fuses/relays and integrated circuits that allow for programmed control and distribution of power to components on Chrysler vehicles. The TIPM does not have processing power; it’s mainly a delivery and storage device with vehicle data stored
