A Tale of Two Fords - Transmission Digest

A Tale of Two Fords

Our first tale is one of those situations in which you are in the middle of nowhere and all of a sudden a warning lamp comes on. This person, whom we will call Mr. Public, was driving his Ford Taurus equipped with an AX4S on a lonely stretch of road at night when suddenly the transmission-temperature lamp came on. Fortunately, Mr. Public was able to limp the car into the closest town, where he took the car to the local transmission shop the next morning.

A Tale of Two Fords

Shift Pointers

Subject: Damage caused by blocked lube hole, faulty ground
Unit: AX4S
Vehicle Applications: Ford passenger cars
Essential Reading: Rebuilder, Diagnostician
Author: Pete Luban, ATSG

Shift Pointers

  • Subject: Damage caused by blocked lube hole, faulty ground
  • Unit: AX4S
  • Vehicle Applications: Ford passenger cars
  • Essential Reading: Rebuilder, Diagnostician
  • Author: Pete Luban, ATSG

Our first tale is one of those situations in which you are in the middle of nowhere and all of a sudden a warning lamp comes on. This person, whom we will call Mr. Public, was driving his Ford Taurus equipped with an AX4S on a lonely stretch of road at night when suddenly the transmission-temperature lamp came on. Fortunately, Mr. Public was able to limp the car into the closest town, where he took the car to the local transmission shop the next morning.

Upon initial inspection the shop’s technician checked the fluid and found that it was severely burnt. The next step was to drop the pan and see what kind of damage might have occurred. Considering the condition of the fluid, there was hardly anything in the pan so the transmission was removed for inspection.

When the oil-pump driveshaft was removed one of the sealing rings was a mess and there was some pitting on the shaft where the bearing rides (Figure 1). A number of the plastic washers were also melted, but not much else was found in the way of real damage except when the technician examined the channel plate.

What you see in Figure 2 is the result of that examination as well as the cause of all the problems that occurred.

The delivery sleeve in the center of the channel plate had turned, completely blocking the lube hole in the channel-plate casting (Figure 3). Fortunately for Mr. Public he got the car in for repairs before severe damage to the gear train took place.

Our next situation concerns a different Ford vehicle with an AX4S that came into the shop because it was slipping. Inspection of this transmission revealed damage to the driven sprocket and the driven-sprocket support (figures 4 and 5). The plastic thrust washer between the driven sprocket and the support is impregnated with metal, which you also can see in Figure 5. At this time the technician looked for worn bushings or bearings but found none other than the oil-pump driveshaft bearing.

Further inspection found no reason for the existing hard-part damage, and this made the technician suspicious of a possible underlying problem that may have been pre-existing.

When the transmission was reinstalled the technician checked the battery ground cable and found nothing wrong with it. His next step was to place his multimeter between the transmission case and the negative battery connection to do a voltage-drop test, and he found quite a bit of voltage present.

That’s right, the damage to the driven sprocket and support were the result of a bad ground. In this instance a ground strap installed from a bellhousing bolt to the negative-battery-cable accessory lead removed the voltage from the transmission case.

Just a couple of things to be aware of in your day-to-day experiences.

Special thanks to Bob from Paradise Transmissions in Key West, Fla., for sharing his experiences and photos with us.

You May Also Like

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

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. 

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. Related Articles – 4L60E Harsh 1-2 Shift – TASC Force Tips: Diagnosing 8L45 & 8L90 Shift Complaints – TASC Force Tips: Hydraulics

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

Other Posts

Shift Pointers: What to do when the 62TE TRS tab breaks

How frustrating it is when on a hot summer day, as you go to open a nice cold can of your drink of choice, and the tab breaks off? You are outside, away from any tools to remedy the problem quickly. It now requires a MacGyver mentality looking around at the resources available to get

Shift Pointers: Failures caused by incorrect tire sizes

For years ATSG has produced a wide range of issues related to improper tire sizes on vehicles. Even under-inflated tires have been known to cause issues. Problems such as premature failure with an active 4WD transfer case will occur with incorrect tire sizes. Related Articles – 10L80 and 10R80 pump gear differences – Top 20

Shift-Pointers-Jan-Figure-1-1400
Shift Pointers: Focused DTCs

On occasions when a vehicle’s computer system detects an error, it can set an array of diagnostic trouble codes. The variety and quantity of them require the ability to diagnose diagnostic codes, so it’s nice when codes set that point directly to the problem.  Related Articles – Going the extra mile: Proving your transmission repair suspicions

Shift pointers: High-mileage transmissions and the aches and pains of age

Among the most common four speed-transmissions keeping shops busy today are the Ford 4R70E/W, the GM 4L60-E and the GM 4L80-E. In most cases, this typically equates to working on high-mileage vehicles. Aches and pains come with age and/or high mileage. In fact, when we see a person who looks beat and tattered, some may

Shift-Pointers-November