Is Your 2004 Ford F150 Stuck in Park?

Wednesday, August 4th, 2010

Mine is – er, was. It began as an intermittent – now there’s a word that no wrench likes to hear – problem. Then, one day, Pam almost got stranded.

I’ve got a pretty good relationship with the dealership. They handle most of the maintenance work on this truck mostly because I don’t have a shop manual. (They’re important, y’know, and I have one – or a set – for all of the other vehicles, but that’s a story for another day.) The dealership treats me pretty good. They allow me into the service area to chat directly with the techs and even cut me nice price breaks often enough to matter.

shifter hack - before and after

Shifter hack - before and after.

There’s a procedure in the user manual for overriding the interlock on the shifter. (I wouldn’t have thought so, but Pam suggested looking there. For once I listened. Smart girl.) So override I did and went to let the pros have a look. Two birds, one stone, it was time for the 75K service interval anyway.

A couple of hours later they told me the shifter assembly needed to be replaced. Actually, it was just one part of the assembly, but I had to buy the whole thing: $370 for the assembly, $130 for the labor to install it, plus tax and what have you. They’d have to order it so in the meantime the tech managed to get this one working. My options were to order the part and schedule the swap, or leave it be and see how long the fix would last. When it failed (when, not if, I noticed the choice of words) I could call the order in and they’d take if from there.

I chose to let it go for now and take my chances. That was the end of June and now it’s the beginning of August. I was in Asbury Park one night last weekend when it failed. I applied the override and got on my way.

Today I implemented my own fix, which I suspect will last longer than theirs. Before I continue I need to tell you that I’m not recommending that you perform this hack on your own vehicle. It disables a part of the safety interlock that prevents you from accidentally shifting out of Park. I personally don’t have a problem with that because I’m an Old Guy that grew up without those damned interlocks, back when you could freely shift the transmission however you pleased at any time.

Let me describe the interlock system. There’s a button on the shift handle which, through a series of internal levers, must physically move a lock that trips whenever the lever is placed in Park. That kind of interlock has been around forever. Some column shifters, for example, required you lift the handle toward you before they’d move out of Park. Implementations vary but they all accomplish the same thing. But there’s an additional interlock here, one that prevents the button from moving unless the ignition is on and your foot is on the brake. Naturally, this is an electrical interlock. There’s a solenoid in the shifter assembly that, when electrically actuated, moves a smaller physical interlock within the button, allowing it to move. This second interlock is tied into the ignition circuit and the brake lamp circuit. Yes, what you’re thinking is true; if your brake lights fail in certain ways or if the fuse for that circuit blows, you’re stuck in Park. When the system is working properly you listen can carefully and hear the solenoid actuating as you press and release the brake. The override mechanism mentioned earlier is a tiny lever that, when pressed, simply does what the solenoid does – allows the button on the shifter to move. In fact, when the system is working properly you can see the override lever move when the solenoid actuates. Whenever the lever is not in Park, the lever remains in the override position.

In my case, I knew from testing that the ignition, brake, and brake lamp circuits were operating properly. The intermittent was that sometimes the solenoid would actuate and sometimes it wouldn’t. Solenoids are simple electromechanical devices. I’m guessing that there could be an intermittent open circuit, maybe caused by something as simple as a solder joint gone cold from vibration or age. Or the mechanical part of it is sticky or binding, where the correct electrical signal is present but it can’t physically move, sometimes. Either way, the shifter assembly needs to be removed for disassembly and troubleshooting. There’s where that shop manual, the one I don’t have, would be handy.

My fix is simpler. I took a few small zip ties, daisy-chained them together to an appropriate length, and positioned them such that the interlock override lever is in a permanently-overridden position. The small daisy-chain of zip ties doesn’t interfere with anything and has enough slack that it can be removed without tools, if necessary for some reason. The zip ties are bright yellow so they’re obvious to anyone looking in there.

The effect is that the shifter now behaves as they used to in the 60s. You can’t shift out of Park without deliberation, but you can do so without the ignition on and stepping on the brake.

So, half a grand in parts and labor, before tax? Or a couple of zip ties? The difference will put lots of gas in the bikes. See you on the road.

Sometimes the Problem’s Not Obvious

Friday, July 30th, 2010

On the way back from New York a couple of weeks ago – a spirited ride along the Hudson with the OCC crew – I noticed a rather loud clunking noise that seemed to come from the front end of the Wide Glide. It only happened on the worst of the road irregularities and didn’t interfere with handling, so I made a mental note and pressed on.

Over the next few days I made an effort to find the source of the noise. It sounded like metal-on-metal and it seemed to be getting worse. Neck bearings, fall-away, pinch bolts, motor mounts, swing bearings, everything in the Critical Fasteners list, and a whole lot more, all came under scrutiny. Sometimes, but not often, one thing or another would take a little torque. And several times I was convinced I had found the problem only to find that, no, that wasn’t it after all.

I’ve been convincing myself that major disaster was lurking to strand me, or worse. You know, that whole “death or serous injury” thing that you find on nearly every page of the service manual.

But today I found the problem!

I was riding with Pam. She was the lead bike; I was taking the opportunity to hit every possible hole in the road while placing my hands on everything I could reach. And there it was!

The fuel tank mounting bolts – probably the ONLY thing that had escaped my torque wrenches – had grown quite loose. The front was worse than the rear. Both are easy to reach.

There are plenty of good potholes just down the street from my garage. I guess I’m lucky that way. (Sarcasm cranked to 11. So happens I wrote checks for my property taxes today and I’m disgusted with the road maintenance – or lack of same – in my town. Shovel-ready my ass. But I digress.) A quick road test confirmed the clunk was gone!

Lesson learned: Sometimes noises come from places other than where they sound like they’re coming from. Check the easy stuff first and don’t skip a thing.

2008 Dyna Parts Manual Typo

Friday, April 3rd, 2009

Yesterday I found that the 2008 Parts Catalog for the Dyna, publication number 99439-08A, contains a typo.

On page 64 there is an illustration (duplicated on page 66) of the front fork. The screws for the axle holder (end cap) are shown as having different lengths and index numbers. Index number 1 is listed on page 65 as part number 4042, which is correct. Index number 31 is listed on page 67 as part number 46614-06. This is incorrect, as are both illustrations.

According to an H-D tech I spoke with yesterday, you should use two part number 4042 screws to secure the end cap, even though the illustration shows a shorter screw on the trailing side of the cap.

It logically follows that the lockwasher, index number 3, part number 7062, should be used in both places as well.

Violating the First Rule

Friday, June 20th, 2008

The first rule of working on color TVs is simple. You remove your rings, your watch, and so on. Some take the rule a step further and keep one hand in their pocket, unless it’s needed for the task at hand.

The reason for the rule is simple. That stuff is metal, and there be large electrical potentials lurking within – even when the TV’s been turned off for long periods of time.

Variants of the rule apply in lots of situations that have nothing to do with television repair. One popular variant is removing your tie before working with machinery. You get the idea.

Well, I neglected the rule. The other day I set out to introduce some refrigerant into the air conditioning system of a Buick. I was prowling around under the hood – the engine off and keys in my pocket – seeking the location of the low-side port. It wasn’t jumping out at me. So I’m feeling my way around the lines, my arm snaked into the engine compartment to the shoulder when the FZZZT hit and my left wrist exploded in pain. I hastily yanked out the limb, gouging chunks of flesh from my bicep and elbow. But the real problem was my watch - the one that I had no business wearing, had I followed the rule. The stainless steel band had apparently shorted a starter terminal to ground. The heat had spot-welded the clasp shut and I found myself in panic mode trying to get the blasted thing off. And finally I did, but not before it had burned a rather impressive looking depression into my wrist. No blood from the wrist; it was cauterized but the red stuff had begun to leak from the other holes…

That was a couple of days ago. It’s all on the mend now and most of the pain has subsided. It still looks plenty ugly under the bandage, but it’s improving every time I look.

Lesson learned: pay attention to those rules, they’re there for a reason.

Oh, and the air conditioner? I found the low-side port against the firewall and added the needed refrigerant. It’s working fine again. Anybody want to buy a Buick wagon?

A Wrench Report of Very Little Consequence

Thursday, April 3rd, 2008

Yesterday I dealt with a minor problem with the Harley, one that had been bugging me for a month or so. When applying the rear brake the stop light wasn’t coming on as quickly as I would like.

I was thinking that it might have something to do with the master cylinder rebuild I did some months back. That wasn’t merely convenience, it was a necessity! The pliable parts of the piston had largely disintegrated leaving the rear brake absolutely useless. The switch is actuated by hydraulic pressure so perhaps a bit of debris had made its way down the line and into the switch. Odd, since I completely purged the circuit and bled it thoroughly as part of the rebuild.

I noticed the trouble with the stop light during a pre-ride check so I bled the circuit again. The trouble cleared but soon returned. Another bleed, another temporary fix. This time when the trouble returned I did the electrical checks (all good) and gave in to replacing the switch.

So yesterday was the day. Luckily the local dealer had one for me and lightened my wallet by a twenty. I considered myself fortunate; they usually don’t have whatever part I happen to be looking for. Since it was my first visit to the dealer since they stocked the 2008 models I couldn’t resist browsing just a little…

Back in the garage, it took about fifteen minutes to replace the switch (with a metric wrench, so much for American Iron, eh?) and bleed the circuit yet again. The stop light was back to functioning normally at the lightest pedal touch.

I suppose I should have inspected the old switch to try to determine if it had any debris in it causing the trouble. But I just pitched it in the bin, grabbed a helmet, and went out for a test ride. Today they picked up the trash.

A Question of Lubrication

Thursday, July 12th, 2007

My garage door had been making a little extra noise and seemed to be moving just a little bit slower lately. I did what anyone would do – I checked the log and found that I had neglected my lubrication duties! So I pulled on a pair of latex gloves, grabbed an old towel for the inevitable mess and went to work. I mopped up the old grease from the tracks – the towel collected the gobs of gritty goop nicely. I shot the rollers and the chain with fresh lithium grease. I ran the mechanism several times, paying attention that I’d gotten the grease into all of the moving parts. It appeared that over the years the chain had stretched some and I wondered briefly when it would fail…

And suddenly it stopped, mid-cycle! What’s more, I think I saw wisps of smoke curling from within the motor power head’s housing. Smelled like… and I would later confirm… eau-de-silicon. More precisely, the motor’s startup capacitor was had fried.
(more…)