Tears for Gears
Well, among the final prep for departure items on my list is maintenance service that’s due on the Mighty Furd, and I also wanted them to check the front wheel alignment and check the front suspension parts, since the tires have been insistently cupping (wearing in weird and warpy concave patterns). That usually indicates suspension problems, and it’s been going on for a couple of years. The cupping transforms the aggressive Cooper ST/Maxx treads from their normal whine to a sound that closely mimics the harmonics of a blown wheel bearing, just enough to make it unsettling. The maintenance items were to change the coolant (best done every 3 years on this engine), change out the fuel filters (2) along with making sure that the water drain valve isn’t plugged up with sludge, and change the oil and filter. The service writer suggested changing the rear diff oil if not already done, which it has not been, which he said was normally due at 90,000 miles. Naturally, I suspected foul play here to drum up business, but agreed to have that added in. As it turns out, it was due at 100,000 miles and I just reached 105. Missed that one. Total bill when it was all over, $730. I’d suspected $600 going in, not including the diff change, and had braced myself for it. Didn’t stop the hanky from having to come out. The other people in the waiting room understood, but I don’t think the cashier likes to see grown men sobbing into one. She did pat my shoulder and say “There, there, now …Check or credit card?” I suspect she rightfully tagged me as one unlikely to carry that much cash. Ever.
I was in by 7AM and left at about 2:30, the main drag being that you normally don’t want to drop all the coolant out until the motor has cooled down some. I sensed bad news coming when the work was done and the writer was not smiling. He herded me toward where we could sit down. Turns out some more work would ultimately be needed. He gingerly began with a bad $11 radiator cap before getting to the real issues. I wasn’t all that surprised, but the cost estimate was definitely not reflected in 1972 dollars, I can tell ya. The serpentine belt tensioner on the front of the motor was shot and off-angle, which had worn the belt itself a heap. That accounts for the weird bird-like chirping sound that the Furdster emits about half the time it’s first started up. Doesn’t sound like a slipping V-belt, but is more of a high-pitched, metallic chirping sound. He recommended fixing that as a priority, since if the belt decides to vacate the premises in the middle of nowhere, that could create an interesting life experience. The replacement process concerned me, though. The engine compartment is so constipated on the 6.4 that it’s not unusual at all for such things to require tearing out the four radiators just to get access to the tensioner. The service writer consoled me, saying that they had special tools that made this unnecessary. However, it’s not a contortion-free exercise, and requires over two hours alone to do.
The tire cupping is caused by a combo of three things in this case. The first is worn ball joints. All four. Since my last experience with a straight-axle pickup was a 1958 GMC that needed a front end rebuild at about $430, this was a surprise because that one used kingpins, not ball joints. Maybe you can’t use kingpins on a powered axle, I don’t know. It also needed two drag links. I can’t think of any way to concisely describe what they do in plain language, so let’s just say they tie together some of the steering stuff so’s the front wheels head pretty much in the direction you want them to. This was disappointing mainly because part of my considerable fame is based on helping steering systems last a long time, by turning the steering wheel only when the vehicle is clearly rolling. If you’re on pavement, the extra effort it takes to force the front wheels to change position while stopped is a component killer. So much for that here. Actually, this 2008-2010 Super Duty series is known for early wearout of the ball joints but, like getting laid off, I never expected it to happen to me. Surprise! This front-end work by itself would take 7 hours, the cost of which, plus the parts, made me pass out right then and there. I came to later, hearing the service writer’s voice in a dull, echo tone as I slowly regained my senses. When I opened my eyes, he stopped pounding on my chest over my heart. I checked. My wallet was still there.
The third contributor was a surprise as well, but was one that rang a bell in my brain-pan. Shocks. “The Tech says they aren’t heavy-duty enough,” he said. It wasn’t too long ago that I replaced the shocks with Monroe Magnums, which are better than base but not high performance. I’d initially been pleased when I first had them installed because they were better than the worn-out OEM (Original Equipment Manufacturer) shocks. But additional time and road conditions showed them to be not that much better. The originals had lasted to 81,000 miles and had two traits that stood out while they were still working well (up to about 70,000). Idling over speed bumps was up-and-down with just one more partial bounce afterward. Slipping a rear tire in dirt or gravel, let alone going into real wheelspin, resulted in the axle staying solidly planted no matter what, since the shocks are staggered to combat axle hop. Once they wore out, a speed bump became a pogo stick affair with the heavy diesel engine up front, and the rear axle shaking during even slight wheelspin on gravel. That’s hard on the driveshaft U-joints. The new Magnums were better in these regards, but not much, which made me wonder what was up. I’d always had good luck with them on cars. Now, with just 24,000 miles on these, trying to power up a dirt slope in 2WD can be a clumsy, juddering affair that requires a stop and a shift to 4WD. This is all odd, because carmakers so often source their shocks (and suspension parts) from “aftermarket” sources, like Monroe. They’re just built and valved to the carmaker’s specifications. Normally, I’d be of a mind to hold off on shocks until they go limp, but because of the simple performance differences, it’s plain to me that I bought crappy shocks, and at a price that wasn’t all that much less than OEM shocks. I never buy OEM shocks, but there’s such a large difference in how these perform during my kind of use that it’s worth it to me to replace them early. They will hopefully be twins of the originals. How they will deal with tires that weigh twice what the originals did has yet to be seen.
The writer said I could hold off on the suspension and shocks until next year, since by that time, I’d be ready for new tires (and brake pads) as well. I’d forgotten that I’d replaced the front brake pads at 35,000 miles, so I’ve got 75,000 miles on this pair so far. The rears are still the originals. I only know this because I’ve scanned just about every service record since new – my memory isn’t that good! Waiting such things out is a way to lessen the financial trauma. After all, the Mighty Furd doesn’t wander a bit on the interstate, but then again, it doesn’t signal a flat tire, either. It’s a tank. Fortunately, I’m not running so thin on finances that I can’t handle having the whole thing fixed, given a little rearrangement of accounts. This has been an expensive winter up to this point. So there’s no significant financial advantage to taking all this stuff piecemeal and allowing the loose parts to continue to have their nefarious effects on each other. I’m more of a mind to see if I can restore the suspension to as close to new as I can get it, so I asked him to order the shocks – the only parts not already in stock – and schedule me in for Tuesday. Get it over with. I’ll try not to post about that event, because it will cost over 3,100 bucks, and I’ll likely be crying too hard to type anyway.
On the way home, I felt good about that decision. Then I realized that I had been lax in my description of the coolant change I’d wanted. I’d wanted only a drain, hose-out and refill, but I hadn’t specifically said not to perform a flush on it. Per good accepted practices, they flushed it out before refilling, with the usual dealer gizmo that isn’t the same as the arduous, literal all-day chemical complexity that Ford recommends for this engine. Under Ford’s scheme, a coolant flush and refill can cost close to $1,000. There’s a reason for that, however. The oil cooler and the cooling system are intimately linked as part of the emissions system. In that link, the coolant side of the heat exchanger has a multitude of tiny passages in order to capture as much heat as possible from the passing oil within such a confined space. It works fabulously when it’s new and everything is clean. Run it for years, however, particularly if the coolant is not maintained, and clumps of crud begin to accumulate in the engine’s cooling passages, much like buildup in your vascular system. Break enough of that vascular crud loose to circulate around, and it’s eventually going to plug something vital, like your brain or your legs. You pretty much need those, even though they may not actually be used much. The Ford factory approach is better, but can still not be successful. Overall, it could be considered to be better not to flush at all. You pays your money and you takes your choice. Mine’s always been flushed by default, so this one is just one more.
The 6.4’s plugging point is the coolant side of the heat exchanger, referred to as the engine oil cooler. As I said, all those tiny coolant passages can plug up easily, and it’s inevitable. That’s why obsessive maintenance is so critical on these things. Normally it takes quite awhile, but it can be sped up quickly by flushing the crud out of the cooling system, which can’t get through the tubing and takes some number of those tubes out of action, reducing its efficiency. It eventually doesn’t cool the oil very well and the oil gets hot enough to break down and become a lousy lubricant for parts that are under a great deal of stress. There are a lot of other bad coolant-related side effects that destroy related components and systems further down the line, all of them financially catastrophic, but I won’t bore you more than I have to. Too late? Then let’s drive in the final nail. All that emissions gear and the havoc it can cause to the engine when any of it goes rogue means that the entire powertrain must be festooned with a basket-full of sensors so that the main computer can throw a warning light, or trim down power, or stop the engine if it thinks that might save it.
I recently got me a gizmo called the ScanGauge II that plugs into the diagnostics connector under the dashboard and reads what the computer is seeing from the sensors. Besides detecting error codes, it can also monitor data real-time. Assuming that the sensors are working properly, this lets you monitor the engine yourself and hopefully catch developing situations before one goes critical and the computer must intervene – hopefully not too late. This can be pretty valuable if you drive cross-country twice a year through Podunk towns, and you know what to look for. For example, the oil temperature should never exceed the coolant temperature (in the Ford 6.4) by more than 15 degrees. If it does, it’s a sign that the engine oil cooler is shot and requires an immediate replacement – that in turn requires the cab to be removed from the chassis in order to get at it. Just imagine how much that costs. Then double or triple it. By the time you get to 15 degrees, other components down the line are likely to be so heat-stressed that they now don’t have long to go either, like the EGR cooler. Better to keep an eye on things so that you can start making decisions well before the computer becomes a tardy harbinger of doom. The ScanGauge, on the way to the dealer, showed its usual spread that ranges from 3-6 degrees at 65 MPH, the oil being a tad hotter than the coolant. After the flush, the spread immediately widened to 6-9 degrees, with the oil running hotter than it did before. That’s an efficiency decrease of the oil cooler, most likely due to the cooling system flush plugging some more tubes. This variance was less consistent though, which I’m guessing might possibly stabilize as the engine burps trapped air out of the cooling system as it heats up and cools down a few cycles. I hope. I’ll be more careful next time, when in 3 years the next coolant change is due.
The ScanGauge II offers a pile of choices about what you care to monitor, and it displays four continuously at a time. The other two I’ve chosen are exhaust gas temperature closest to the exhaust manifold, and exhaust backpressure caused by the Diesel Particulate Filter. The DPF collects black soot that would otherwise go out the tailpipe. These choices allow me to know whenever the engine is in regeneration mode (incinerating crud out of that filter). That’s worth knowing because regeneration mode on the 6.4 does so by dumping extra fuel into the two rearmost cylinders to heat up the DPF, to try to clear it out a bit so that excessive backpressure doesn’t cause joyless havoc in the turbo or the engine itself. Regeneration mode also causes a little of this extra fuel to leak down the cylinders into the crankcase, diluting the oil and ruining its lubricity. I think Dodge/Cummins dumps fuel into the exhaust manifold. How they ignite it, I don’t know, and I wonder how hard that is on the manifold. I also don’t know which approach GM/Isuzu takes. At any rate, shutting the engine off while it happens to be in regeneration mode will just delay it until conditions are right for it to start over right from the top, diluting the oil more than it would have if it had been allowed to complete its cycle, which can range from 5 to 40 minutes. That’s right, you pass your exit and keep going. Regen mode causes the exhaust gas temperature to sail from 500 up to 900+ degrees, and the backpressure to temporarily drop by a few pounds. Using the dipstick to see if the engine is worn and burning oil is pretty much a waste of time because, if anything, the oil level will either hold even or continue to rise until the next oil change. Completing the regen cycle can cut this down quite a bit. Sheesh. These kinds of shenanigans are why the Mighty Furd will not be replaced by another diesel truck (or turbocharged gas engine) of any brand, should the unthinkable happen. It’s the emissions gear.
If you care, I got my ScanGauge II from Bullet Proof Diesel, who specialize in feeding off wounded 6.0-liter and 6.4-liter Powerstrokes. Unlike any other vendor, they pre-program the ScanGauges they ship so that the buyer does not have to go through the rather painful ordeal of keying in multiple long codes using just the few buttons on the face. No touchscreen smartphone keyboard here. With the one they offer, all you do is cycle through the choices for each of the four displayed values that you want to see. It takes however long it takes you to make up your mind. I think their price was $10 more than Amazon and everybody else, and the pre-programming was well worth it. In selecting such a device to buy, one needs to stay awake. Many such gizmos are for error code diagnostics only, and many of the rest are not designed to read monitoring display codes specific to emission-controlled Powerstrokes. They cover only the very basics, but they don’t tell you that in their sales schpiel.
The Grand Tour starts within a very few weeks, so you three readers that are left will have something to look forward to!