Automatic Transmission Repair

More Technical

ZF9HP48, 948TE Line Pressure Control and Diagnostics

The units are utilized in the Acura TLX and MDX, Chrysler 200 Fiat, Honda CR-V, Jeep Cherokee KL and Renegade, Range Rover, and Land Rover, to name a few.

A 5R110W With Transmission Overheating

A laser gun was used to check the temperature of the oil pan sump, confirming an overheating condition did exist.

Trying to Stop the Wheel Hop on Ford Edge with 6F50 Transmission

The 2014 Ford Edge SEL with a 3.5L engine (figure 1) and a 6F50 transmission can also be equipped with an AWD system. This would include a Power Transfer Unit (PTU) attached to the transmission with a rear driveshaft going to the Read Differential Unit (RDU). The RDU comprises a differential assembly along with a

Sherlock Holmes Approach to an AB60 No-Move Situation

The effectiveness in diagnosing automatic transmission malfunctions is an art form. Although there are similarities among the wide varieties of transmissions on the road, each transmission has its own peculiarities. Aside from having mechanical, hydraulic, and electrical hardware systems to contend with, software/programming issues and various vehicle platforms make diagnostics much more difficult.  Using scopes provides

ab60
GM 6T40 Pump Identification Guide

The 6T40 was introduced in 2008 for General Motors front-wheel-drive cars in the Chevrolet Malibu and has gone through several changes throughout its three generations, specifically in the pump area. The 6T40 is closely related to the more lightweight 6T30 and the heavier duty 6T45 and 6T50. Generation one started phasing out during the 2012

Seeing the Forest AND the Trees

They say that the proverbial phrase “I couldn’t see the forest for the trees” means that a person or organization cannot see the big picture because it focuses too much on the details. I have seen this phrase used after days of diagnosing a transmission problem without resolve, yet the cause is staring you in

The Manifold Pipeway

The Honda six-speed transmission has been on the bench of many specialty shops for one reason or another (figure 1). But, for those of you who have yet to lay your hands on one, mounted on the upper side of the unit is one of the largest, if not the largest solenoid and pressure switch

8L90 Vacuum Testing

Below are the diagrams for vacuum testing GM 8L90 transmissions. Note: OE valves are shown in rest position and should be tested in rest position unless otherwise indicated. Test locations are pointed to with an arrow. Springs are not shown for visual clarity. A low vacuum reading indicates wear. For specific vacuum test information, refer

4L60E Harsh 1-2 Shift

The 4L60E transmission platform has been in service from 1993-2015; that’s 22 years. It amazes me when a transmission that has been around for this long can throw a new twist on a common problem and blindside you. Let us have a look at the systems and potential problems in a 4L60E that can cause

TASC Force Tips: Diagnosing 8L45 & 8L90 Shift Complaints

Sometimes attention to the smallest of items can save you big dollars.

TASC Force Tips: Hydraulics Fundamentals: Check Valves

while check valves are fairly simple in design and function, they can cause various shift issues and clutch failures when not working correctly.

Shift Pointers: Mazda Sensitive to Pressure

A Mazda with the “SKYACTIVE” FW6A-EL transmission uses pressure switches to monitor the clutch application. When engagement pressure is supplied to the applicable clutch and brake, the oil pressure switch contact point closes. The TCM detects that clutch engagement pressure is supplied to the clutch/brake by opening/closing the oil pressure switch contact point. There have