5-year 06 Nav owner (& life-long wrench) & while I've never owned the Ford, a neighbor had an 05 Expy which I did a lot of maintenance on for him..... so I got a decent comparison.
Just about everything above is pretty spot-on.... Only thing not mentioned above is the transfer case of the 4WD variant.
The Navi's case is a lighter-duty unit with no low-range option. While the Expy got Ford's usual 4WD case with low-range. Not that Ford ever expected Lincoln buyers to be the off-road enthusiast types.
THX Certified sound system is std in a Navi. Optional in the Ford.
One other difference no one mentions which I believe to be unique to the 05-06 Lincoln, is engine braking.
If you take your foot completely off the accelerator pedal in an 05-06 Navi the torque converter does not unlock & allow the vehicle to coast. I've actually had it downshift, while rolling downhill, trying to keep the vehicle from speeding up.
You may not like this feature.... until it comes time to do brakes. Like I said, I've owned my Navi for 5 years, I JUST did my 1st brake job on it a couple months ago. Now, I checked the service records that came with the vehicle when I bought it. It's last brake job was at 91,000 miles. It's now at nearly 150K, you do the math.
We're not talking about a Focus, or a Honda Fit here. This thing's curb weight could be described in ton
s (plural). That's a long time between brake jobs for a behemoth such as this.
& that's a good thing. Those carbon-ceramic brake pads this thing uses aren't exactly sold at give-away prices either. However, that does also mean that the rotors will be pretty close to shot when you do finally get around to a brake job. So, don't even bother trying to get 'em turned, just get new ones.
Besides, it isn't all that bad once you get used to it. If you don't want the converter to remain locked, just keep a slight amount of pressure on the pedal, it'll unlock & let the vehicle coast. It'll become 2nd nature eventually.
Other than that, not much I could add save for some details & personal thoughts...
On the fuel: Depending on trim level, a Navi is 4-6 hundred lbs. heavier than it's Ford-badged cousin. A good bulk of that weight is in sound-deadening. Hence the quieter environment inside the Navi. I've got 150K on mine & even at this point, you can't tell it's running unless you look at the tach. My wife still turns the key to start it occasionally while it's already running. Engine & road noise even at highway speeds is non-existent. Swing a Navi door & then swing the Expy's & you can feel the difference in weight just in a door.
Another factor may have been the transmission difference. The Expy had Ford's tried & true 4-speed, while the Navi received a six-speed ZF 6HP26 for 2005 & 06. (Originally developed for BMW's 7-Series - & later built by Ford under licence for the Gen3). Allowing it to operate in a tighter RPM range.
If you search around you'll see both listed as 300HP. I don't believe that's entirely accurate however. To deal with the added tonnage & different trans, the Navi's 3-valve was tuned differently. Not a whole lot, & it's certainly not so much that you'd notice unless you've driven both back to back, but that did bump the octane requirement to the use of premium fuel. If you try to run a Navi on regular, the ECM will back off the timing & that's something you WILL notice. Both in feel & MPG.
I'll whole-heartedly concur on 2nd Gen being my favorite of the series.
1st reason: The Gen2's 4-corner air ride. I live in Maine, up here a Prius is considered "pot-hole filler material".
Sure, I get the complaints. Yea, the air leaks were an issue that caused many to throw the airbags in the trash & convert to spring-ride. Especially up here where winter temps only aggravated the issue. But, when I found out I could replace all 4 corners with complete brand-new units (thank-you Suncore Industries) for only $400 more than a spring conversion kit, complete with billet aluminum mounts that DIDN'T become leak-prone (rust would build-up between air-bag & stamped-steel mount - causing the leak) I ordered replacement fronts 4 years ago that are still going strong. 4-bolts, one electrical & one air-line connection per corner & the whole shootin' match was done in less than an afternoon with no re-alignment required for just a couple Bennies each. Why wouldn't you? Ford should have stuck with it for a little longer & sorted it out. I'm still on leak-free 4-corner air ride at 150K. Pot-holes? Speed bumps? What are those?
2nd reason: A naturally aspirated V-8. I'm not a fan of turbos for a daily driver. & sure, Gen3 still has the 5.4 as well, but it lacks the air ride. & then even that disappears in 2015. Oh, how I wish the govt would stay the h*ll out of the way & let Detroit build vehicles people actually WANT to buy & drive. But, that's a whole 'nuther sermon. If Ford had stuck with 4-corner air-ride a little longer, or come out the the "L" version a little sooner, I'd have my dream ride.
Beyond all that what have I learned from the last 5 years of Gen2 experience?...
1st off - Don't let anyone scare you off the 5.4 3-valve because of the camshaft timing gear or any other "issues". If you really WANT to get scared here's a video from YouTube's (in)famous (cough)alleged(cough) "Car Wizard"...
I'm going to take serious issue with his claim of the 3-valve being the "worst engine design ever". I can think of more than a few of those just off the top of my head. Any BMW M5 owners want to chime in here with their Vanos pump experiences? Anyone else here old enough to remember the aluminum block Vega? Oldsmobile "Quad-4" anyone?
But specifically.....
4:45 - Oil Drain-back Not Adequate - Bovine Excrement - It sure doesn't take a rocket scientist to debunk this one. When in Hades was the last time the oil got changed in that engine? Blaming lack of maintenance on the design engineer is about as dumb as blaming him for the engine quitting because he wasn't savvy enough to not realize you might be dumb enough to fill the tank with diesel.
8:55 - Engine Replacement History - Proves Nothing In Context - To understand what I mean by "in Context" back up to 8:30 where he'll clue you in to the obvious flaw in his own conclusion that this proves something. Sure, the engines in the Navi, Expy, & F-series all the same. Also, during this entire 3-valve era, the Ford F-150 was the most popular vehicle sold in all of North America. Not just most popular truck, most popular VEHICLE. Now, let that sink in & think about it for a minute. Is it likely that the engine that's in the best-selling vehicle in all of North America might have it's share of failures along the way? Of course it will. However, what's that failure rate as a percentage of total units built? THAT number might actually tell you something. Just number of failures by itself means nothing. Not only that, how many of those were due to the obvious lack of maintenance of our example here? There's more questions than actual answers in Mr.Wizard's little "Let's S**t on Ford" rant. (in other video he admits to not being a Ford-brand fan)
If you build 100 engines & have 5 failures, and I build 10,000 engines with 200 failures, who built the better engine? (you do the math)
I wonder how many listings he'd find if he did a similar search for "LM7"? I'd bet that list would be just as long, & no one I know considers that a "worst engine" of GM's history. Far from it.
H*ll, if we toss the 4.6L version of all those Explorers & Mustangs into the mix, I can make the case that Ford's Modular V-8 could be dubbed the "Small-Block Chevy of the 21st Century".
12:18 - Spark Plugs - Wakey, Wakey, Mr.Wizard - Someone wake this guy up & tell him that we've had one-piece plugs for this mill for at least a decade now. Personally, I use Champion's 7989. But, there are others if you prefer.
In another video he stated that he charges an hour labor
PER PLUG to extract a broken 2-piece original. It's been a LOT of years since I was a professional mechanic (1980s-90s). At this point I'm old, and REALLY slow. However, I needed to extract 2 of the originals from mine. Once I learned how to use the extraction tool, the 2nd one was less than a 10 minute affair to remove. OK, so I used a small tube on a vacuum down the hole & then inspected for debris with a bore-scope afterward. Still, whole process start to finish was less than 20 minutes.
In yet another video he lavishes praise on the previous 2-Valve design as "Ford's BEST V-8 Engine ever".
Yes.... I'm serious.... stop laughing.... really.... just stop.
I wonder what kind of increase in stock price the makers of "Heli-Coil" saw during the 2-valve era?
I mean, if you're REALLY talking about "design flaw", that might be one.
If it weren't for Tyler Hoover, this guy's YouTube followers wouldn't hit double-digits. He should be fixin' Tyler's hoopties for parts-cost out of sheer gratitude.
Self-proclaimed "Wizards" & other false-prophets aside. All the complaints about the 3-Valve 5.4L are easily avoidable.
1. Oil Changes - Ya gotta change the oil.... regularly. No, you DON'T have to change it every 3K (sorry Mr.Wizard). This IS the era of good synthetic oils that can last way more than 3000 miles. But, I'd say around at least every 10K tops if you use a good
full synthetic oil from a reputable brand. (Mobil1, Amsoil, Castrol, Valvoline, Pennzoil... pick one) I know, some are even claiming 15K these days... but, I'm still a tad nervous about going that far.
Personally, I do it twice a year. Once when it gets it's annual State inspection. (He's got it on the lift already, why not?) 6 months later I do one.
Remember something, your Owner's Manual was written nearly 2 decades ago. We're now in 2021. Oil formulations & quality continue to improve, & nobody "updates" owner's manuals.
On that note, here's another area I get grief on all the time, but my results speak for themselves. When that engine's odometer hits (or closes in on) 6 digits, swap to a heavier weight oil. Personally, I'm using 10w-40. Now, if you ask all the "internet experts" my engines should have gone all Chernobyl on me years ago. All the "Factory Trained Techs" (they're not called "mechanics" anymore, & they're kind of touchy about it too) will give you the "oil is speced from the factory because of internal clearances" and what-not... etc, etc, yada, yada, yada, blah, blah blah...
I couldn't care less what "factory clearance/tolerance" you're yammering about, if I take that engine apart after 100K miles there's no way in Hades that clearance is now the same one it left the factory with. I've now got more space to fill & try to maintain pressure & film strength with. Give me something a little stouter for the job so my oil pump isn't begging for mercy if the RPMs climb while I'm trying to hit 70 before I run out of on-ramp.
Is the fuel mileage going to suffer? Yea, a tick. But, I make up for that with longevity. In the current fleet I've got a 4.8 Chevy with almost 200K on the clock. Never been apart, & still runs like it left the factory yesterday. I'll take a 1 or 2 MPG hit if I can get another 5-7 years of life out of a vehicle before I need to buy another one. Again, you do the math.
Every vehicle I've replaced in my life has had near or over 200K on it & was still running. Of course, up here the chassis starts rotting out from under it at that point. So, for me, its 10w-40 after 100K. If it ain't broke, don't fix it.
Only thing I've got not running 10w-40 is the wife's 2011 MKX. But, even that is now on 5w-30, vs the called for 5w-20 since there's over 70K on it.
On this note, if you live in a cold climate, give it a minute or two on the 1st start in the morning before you hammer on it. It does take a few seconds to circulate that stuff when it's chilly out & thermometer can't break out of single digits.
2. Valve Timing System - On the valve-train timing gear issue specifically, beyond oil changes, there's another bump in that road... the valve timing solenoids. Or, more specifically, the debris screens on 'em.
Regardless of how often you change your oil, there will be a certain percentage of unfiltered oil circulated through your engine at certain periods. It's baked into the cake, learn to live with it. That oil filter has a bypass valve in it. If the downstream pressure is less than the upstream pressure, that filter goes into bypass. This will inevitably happen more often as the engine gets older. Things wear, clearances open up, it gets harder to maintain downstream pressure. This presents itself as a problem due to the way the variable valve timing system is designed. It relies on oil pressure. The feed openings to the solenoids are covered by debris screens. Any particles in unfiltered oil will collect there. Clog 'em up enough & won't matter how long or how far open those solenoids are you're going to be starving the timing system downstream of oil. Hence, all the premature failures & rattling timing systems.
If yer askin' me, those solenoids should be treated as a normal maintenance item. When it's says 100K on the clock, regardless of the lack of "check engine" codes for 'em, replace 'em. Might not be a terrible idea to do it again at 150K, just for giggles. They're cheap, & on the 05-06 3-Valve you don't even have to remove the valve covers. Just buy new plugs. It's not even a one-beer job.
You know the 5.4L valve-train timing gear issues all the "Internet Experts" will tell you are guaranteed somewhere between 100-130K miles? Well, I've got 150K on my Navi & it's as quiet & well-behaved as it was at 150 miles. & my neighbor sold his with 175K on it, with the original valve timing gear still in it & working fine. So, take that Mr.Wizard & other Armchair Prophets of Doom.
Before you buy, here's a quick timing gear test you can perform before any money changes hands. Start it up & let it warm-up while you're looking the rest of it over. Once it's up to temp get in & stand on the brakes. Roll the window down so you can listen (leave the hood open too - just because). Take the engine up to about 2000 RPM while you're hard on the brakes (2500 if you can get there without over-powering the brakes) to load-up the engine. Then snap your foot off the throttle. If you hear a "rattling" noise, prepare for a cam timing gear replacement in your not too distant future if you buy it. (use it as a bargaining point)
3. Spark Plugs - At this point this really shouldn't be an issue anymore. However, that said, should you become the proud owner of a 3-Valve that's never had the plugs changed, here's how to try to get out as many as you can without breaking them. Get out your impact wrench. Yup, you read that right. Dial it back to a low setting, don't just go full bore & hold the trigger. Give 'em very short, quick, "bursts" out of the impact gun. This will usually result in most, if not all, of 'em coming right out. (Feel free to forward this advice to Mr.Wizard) My 1st plug change involved 2 broken plugs. One was cyl.5. The very 1st one I tried to get out... manually with a ratchet. The rest all came right out with the impact except for cyl.4 which I attribute to needing to use a swivel on an extension to reach. (although, #8 came out just fine).
If you DO break a 2-piece plug, extracting the bottom half is no sweat with the extraction tool. Look down the hole & see if the lower porcelain is still intact. If it is, reach down there with a screwdriver, break it off, & vacuum it out. Read the instructions with the tool & extraction is an easy process. I inspect the cylinder for debris with a bore-scope just for piece-of-mind. But, I've heard some guys just cycle the engine a few times without a plug in it so anything in there is likely to blow out.
It's best if you can borrow or rent the tool. You won't need it more than once. Unless of course you're dumb enough to put 2-piece plugs back in it. Or you can charge somebody an hour's worth of labor per plug for an extraction.
Install one-piece plugs. Coat the threads & barrel lightly with anti-seize... job done.
4. Mystery Coolant Loss - You may run into an unexplained gradual loss of coolant. You pressurize the system, you check everywhere, you can't find a leak, the system will hold pressure forever. What in the name of???.....
Step one, let it sit. Preferably overnight. Even better if it'll be a really cool night. Now, go out & open the hood. Feel all around every one of those "quick connect" heater hose connections. Is one of 'em wet? You found your leak.
Yup, it only leaks when it's cold. How do you like that one? It drips when it's cold, then when you fire it up & head down the road it seals up & the heat takes care of any tell-tale signs of drippage... so you can never find it.
This isn't really unique to the Modular V-8, it's the same for any Ford with those fittings. They can develop an issue where they drip when they're cold & seal up just fine once they get a little heat in 'em. The aluminum the tube is made of that they fit over expands & contracts a lot with temperature. Once those fittings get a little age on 'em & the rubber o-rings that do the sealing part start to harden a little then the rubber can't keep up with the dimension change. Bad news here is if you have the rear seat heating option so that the hoses have factory T-joints in them, you might feel a pain in the wallet replacing 'em.
If you're REALLY lucky/unlucky, you have your #3 spark plug boot's vent hole oriented just right, and that particular fitting directly over it is the issue, this will eventually manifest itself as a cold misfire in the #3 cylinder. Then the fix is a two-fer. You fix the misfire & the mystery coolant loss in one shot. Don't ask how I know this, or how much hair it cost me in figuring out they were related.
5. Where's the Dipstick? - Specifically on the 05-06 Navi with the German 6-speed transmission, don't try to find a dipstick. There ain't one. The ZF 6HP26 requires NO maintenance. Unless it's been leaking, don't worry about it. Yes, seriously. Ignore what you've heard. It's perfectly fine for 200K+ miles with absolutely ZERO maintenance. It's been around since 2001, & there are thousands of BMWs with over 200K on 'em that have never had this transmission apart. It's probably one of the most bullet-proof automatics ever built. It's no small wonder that Ford decided to make their own version of it. It was a wise move.
Seriously, if it hasn't been leaking, & it's working just fine, leave it alone. You know, the old, "If it ain't broke, don't fix it" thing.
Not to pick on Mr.Wizard more but, just because the fluid is brown doesn't mean it's bad and/or "worn-out". (go find the episode of "Hoovie's Garage" on YouTube where he gets his Maserati serviced at Mr.Wizard's) If you doubt me on this go down to your local BMW dealer & ask for a bottle of "ZF Lifeguard 6" transmission fluid. After you've gone to the bank for enough money to purchase that bottle of liquid diamonds, pour some out & tell me what color it is. Go ahead.... I'll wait....
By the way.... Maserati's issues with the ZF 6HP where electronic, & self-inflicted wounds, not the fault of the transmission. They thought they could program it better that the cats that designed it.... which obviously didn't work out too well. If they really wanted to do a Manual Mode right they should have asked for help from Aston Martin.
Should you need to replenish the fluid in a ZF 6HP, just swallow hard, put on your big-boy pants, go rob a bank, & buy the right stuff.
DO NOT do a Google search for "ZF6 fluid" & think you can just dump Mercon-V in it. That's acceptable for the
MANUAL ZF S6. Not the automatic. (yes, Mr.Wizard put the wrong fluid in Hoovie's Quattroporte)
The confusion comes from calling any ZF 6-speed transmission a "ZF6". Which, if you aren't aware there's a difference, might lead you to believe its just another way of referring to the ZF 6HP. Someone talking about a "ZF6" could mean the ZF S6 or the ZF 6HP, which are two different transmissions. & only one of 'em is an automatic. Particularly confusing in our case because Ford put the ZF S6 in a lot of 3/4 ton & up F-series trucks.
Ford used to sell re-bottled ZF Lifeguard 6 fluid for the 05-06 Navi, but no-one around here still stocks it. You can find it on eBay for around $20/liter. However, if you can't wait, your local BMW dealer will be more than happy to sell you as much "ZF Lifeguard 6" as you want. You can try to get away with something cheaper. Some Ford shops will tell you you can use what Ford puts in their version of it, but, that's your gamble. All the ZF 6HPs I've known that made it 200K or better ran the right stuff in 'em.
Now, if you happen across a screaming deal on a 2nd Gen Navi that's been sitting a while (like 3 years), & you experience a slight shudder on light acceleration, that's the converter clutches. The fix is as easy as dumping 4oz of the "friction modifier" Ford sells for the limited-slip rear ends in it & drive it for 1000 miles or so. If it hasn't completely gone away yet dump in another 4oz & it will eventually just go away. Seems the converter clutches don't like just sitting around for years doing nothing. Just remember, you need to have the engine running when you pull the fill plug on the side of the transmission. Unless of course, you enjoy wearing essence-du-transmission as a cologne & paying for some more of the liquid-gold to replace it.
So there you have it.... 5 years & over 40,000 miles of 2006 Navigator ownership, with a few years worth of 2005 Expedition maintenance & test-driving thrown in for good measure.
