Street Smart - September - 2016

Ford Torqshift/5R110: A Shot in the Dark

The Ford Torqshift came out in 2003 and over the years has exhibited its share of problems.

The original solenoid body may have one or five pressure switches, depending on model year. The computer on these vehicles was never programmed to monitor the pressure switches. Ford removed them in late 2004.

The later solenoid body may have one pressure switch with no wire going to it. In this application, the switch is only used as a plug; the remaining four holes were cast over.

These pressure switches were one of the first problems with the Torqshift. The rubber boot on the back of the pressure switch would rupture, causing a pressure loss. The aftermarket quickly came out with a plug kit to correct that.

With no shift valves, all shifts are controlled directly through the shift solenoids, and you’ve no doubt learned the importance of testing or replacing them.

The next common failure in the Ford5R110W occurs when the low/reverse retaining ring pops out of the case groove, causing slips in reverse and severe damage to the case lugs.

Once again the aftermarket came to rescue with a wider and slightly thicker snap ring, providing more outward tension. The increased tension and extra stiffness help keep the ring seated securely in the case groove.

Another common problem is delayed engagement in drive and reverse caused by a worn manual valve. The quick repair for this is an oversized manual valve.

Finally, you’ve seen what happens to the pump when the cooling system isn’t serviced correctly: The transmission fluid cooling system is one of the most critical areas in the transmission repair process. Any debris left in this system can and will find its way back into the transmission and into the super sensitive solenoids. To protect your rebuild, always install an in line filter kit.

Which brings us to the next dilemma:

You’ve been building these units now for over 13 years. You know the problem areas, you know this unit like the back of your hand. You’ve built hundreds successfully; now you have this one problem child.

After rebuilding the transmission, you take the truck out for a road test. It shifts perfectly: a nice satisfying feeling. You stop and go several times. The last part of the test drive you take it up to highway speed to check lock-up. Everything works perfectly.

Now back to the shop. Then out of nowhere the rear tires lock and you almost go through the windshield! You skid to the side of the road, put the trans into park, get out and look under the truck. What happened?

Not seeing anything, you get back in, start it up, put it into gear, and it moves forward. Driving very slowly, you make your way back to the shop. You get your scan tool to check for codes.

And guess what? No codes. Now what? Must be a mechanical component, like the low/reverse one-way clutch or the overdrive one-way clutch is locked on.

So you put the truck on the lift and pull the trans back out. You tear it down again only to find everything looks good. Could this problem be caused by a solenoid not functioning properly? They were all replaced during the rebuild. Maybe it’s an electrical problem?

You’d expect a wiring problem to set a code, but, with the trans out of the way, you decide to check the harness from the TCM to the trans. After spending a couple days testing the electrical system and going back through the unit, you’re still in the same predicament.

This is when you put in a call to the ATRA HotLine. You explain what happened and what you’ve done. The first thing the HotLine tech asks was whether you have any codes. “No,” you say. “There’s your first red flag,” he replies. “With those problems you should have ratio codes.”

So his suggestion was to induce a code by starting the engine and then unplugging the transmission harness connector. Then put the transmission in gear. This should set codes for all of the solenoids. If not, there’s a good chance the TCM is toast.

He went on to explain that he’s seen several bad TCMs causing the transmission to lock up while driving.

So you disconnect the transmission, start the engine, and put the trans in gear. The transmission goes in failsafe, but it doesn’t set any codes. So there’s a good chance the TCM is at fault.

Of course, nothing’s certain; it’s still something of a shot in the dark to replace the TCM, but the odds are looking better. And at this point, what do you have to lose? You’re out two days work and you can’t give the truck back to the customer the way it is.

You check with your local Ford dealer and discover the TCM is only $450 and is in stock. So you pull the trigger and buy the TCM. After installing it and taking the truck on several road tests, the problem appears to be gone.

Replacing the TCM may not be the traditional diagnostic strategy, but sometimes you have to go with your gut… and that’s not just smart… that’s street smart!