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Your expertise and experience with 97-03 F-150 supercrew 4.6L

This is probably gonna open a big can of worms. :slight_smile:

I’ve got a 96’ Taurus with 201,000 miles. I may want to replace it, the whole car. It has been idling rough lately. Can that sometimes be an indication of worn timing chain or EGR valve? My check engine light is on, and I think it’s something to do with the EGR system. Anyway. Deviating from original topic.

With that being said, my taurus gets 24-26 mpg average. Is that normal or below normal. I’m disgusted by the mileage. Long story short my morning commute is 4 blks to county highway and 55mph on county highway for 12 miles, then 70mph for 30 miles and about 12 city blks until I arrive at work. If I drive all posted speed limits I might get 24 give or take. If I drive 60mph the entire way (cept for city of course) I might avg 26mpg. As an experiment I drove 45 mph on an entire tank and got 30 and no better than 30 mpg. I used to have a '92 Mustang GT 5.0 and got 23 mpg (there were alot of variables in that situation) I was impressed with that mpg. I talked to a guy at a gas station that had a 2000 (i think) F-150 supercrew with a 4.6L. I asked him what his best tank was. He said he doesn’t get to take it much out on the highway since he lives in city but his best tank so far was 24 mpg! I wanted to push my Taurus in the ditch!! I don’t think he’s far off. My wife drives '99 Expedition and we’ve gotten 20mpg going 70mph with AC on to Nebraska.

Was that guy pulling my leg though?? If not, I want something MORE comfortable. I’m 6’ tall and 30 pounds over weight and approaching the end of my life span at 30 years of age. :slight_smile: I would like to be more comfortable if I get RELATIVELY same mpg. I’m really eyeing the 4.6L for that reason. I would like to still have V8 since it is a truck. I drive about 70 miles a day round trip. I do not have a problem driving slower (not slower than 55 though).

In the aforementioned truck I would like to look for, can a person change the ring gear in rear end for a lower ratio?? I’m not sure what’s factory and I’m not sure what ring gear my wife has in her truck. Would a lower ring gear ratio help lower rpms on highway by just a little bit?? Or does changing ring gear seem like a circle, making the engine work just as hard to get up to speed, thus defeating the purpose? You would think the engine would work at a certain rate but once at highway speeds the ring gear will make the difference. hmm, anyway. I’ll do whatever it takes to imprive fuel economy. If it can stay close to economy of Taurus, i will be happy as a tornado in a trailer park. Would that be possible? If you own one of these trucks give me all the info/opinions you got. If your friends have one, ask them (preferably not after 6 beers and during nascar).


I know this is cliched to say this, but, “I have this friend…” I went to high school with. Him and his dad are big ford nuts (i am too, that’s all we own). He works on alot of cars on the side to help friends. He personally doesn’t like the Triton motors in these ford trucks/suvs. He thinks they’re a poor design. The biggest thing he was warning me about is that these motors like to blow spark plugs, thus stripping out hole. He cited 2 or 3 examples of guys in town that have had those problems, not just 97-03, but 04-08 as well. Like I said, my wife has '99 Expedition and we’ve never had issues like that. Course, my wife is the greatest driver I know! She babies that truck. Okay, now for the question: DOES THIS HAPPEN? HOW MANY CASES? (RARE?) SHOULD MY MOM BE CONCERNED WITH HER 2002 LINCOLN CONTINENTAL??

I think that’s all I wanted to post. Thank you in advance!!! While I am open to and you are entitled to your opinions, I am partial to Fords. :slight_smile: please keep ford slams to minimum. The best one I heard was “ford figured out the problem and circled it!” (refering to emblem) an old timer told me that.


That is a lot of questions!
I have 2 opinions.
The MPG of the Taurus seems good to me.
And that 24 MPG on your friends truck seems high. It was probably downhill with a tail wind.

I have a 97 F-150 4WD regular cab, with 3.55 gears and 32 inch tires. I get about 14 MPG around town and about 18 on the highway. 24 MPG sounds like a pipe dream to me. I don’t drive the truck all that frequently though. For the 97-03 4.6L’s the lowest stock ratio with the supercrew IIRC was a 3.31 for 4WD modes and a 3.08 for 2WD. And honestly I wouldn’t go any lower than that, unless you like the idea of the transmission hunting between 3rd and 4th gears on level ground at highway speeds.

The early 2 valve modular engines did have a problem with sparkplug ejection, that was largely rectified with the introduction of the P.I heads in 1999. The 04-08 trucks had a problem with the 2 piece spark plugs breaking, they were only used on the 5.4L engine in the F-150 and now they have a 1 piece spark plug. That solves the problem. You mom’s Lincoln uses the 4 valve 4.6L that has different cylinder heads, spark plug ejection isn’t an issue with the DOHC 4.6L

If mileage is your main concern, forget the F-150. If you want great mileage forget a pick-up all together. If you really want the F-150 accept that the mileage will be poor. Don’t try to make it something it isn’t by changing the rear end ratio. The mileage probably won’t improve, could be worse, and you won’t recoup the cost. If you are looking for comfort, hauling capacity, reasonable gas mileage, and can live with universal derision, I would recommend a mini-van. Otherwise, you need to think more carefully about your priorities and how much you want to spend. Take some time and calculate fuel costs per mile. Apply that to your situation. Then you will have an idea what the payoff is for improved mileage.

Personally, having owned a 97 Taurus, your mileage seems low to me. I routinely got 20-21 mpg in 100% city traffic and around 30 mpg on the highway (12 valve engine). I would expect you to be able to get 26-27 mpg on that drive, and that would be pretty typical for any larger midsize car of its time. Nowadays you can do better, but comparing a 2012 model to a 1996 simply isn’t fair.

That said, your posted mileage isn’t far off of what you should expect from your car, and you wouldn’t come anywhere close to that from an older truck (your friend’s claims of 24 are HIGHLY suspicious). I’d wager that your mileage might be affected by maintenance issues. When was the last tuneup? A lot of people that neglect check engine lights neglect simple things like plugs and wires, too… that would affect mileage. And if your EGR system has a fault, that could easily knock down mileage by 10% or more, too… So why not fix it? The most common problem these cars had with their EGR was the DPFE sensor going bad. Those cost about $50 at and a 2 year old could change one out in 5 minutes. Ok, I exaggerate… it might take a 5 year old. If its the EGR valve itself, then you’re looking at $55 for an actual Motorcraft part at Rockauto, and a mechanic shouldn’t charge more than an hour for labor, so total cost should be in the $120-150 range, plus any diagnostic fee if they charge one.

Simply put, I think you can get your mileage up in what you currently have just by doing some cheap repairs and maintenance, and you’ll spend a LOT more money buying that truck, and will end up with a LOT lower gas mileage than you currently get.

Real world 26 mpg is not that bad,in the good old days that were bad that was salivating territory. of course all my friends can get better gas mileage then I do,but my numbers are repeatable-Kevin

The 4.6 began it’s life in the Crown Vic where it has served faithfully for 20 years…They get 24-26 mpg easy, with some able to approach 30mpg. You get a big, comfortable, reliable car in the bargain…

The 4.6L Ford, when compared to many of the engines found today, are a paragon of reliability and durability. Blown spark plugs are usually caused by stripping the threads during replacement…it’s not a big problem…

The Taurus mileage is not really that bad but could possibly be better depending on how well it’s been maintained, tire pressure, and the all important factor of just how solid the engine is mechanically. You state it’s idling rough and that could be due to an open EGR or a cylinder or two going down.
Given the mileage on the car, I’d run a compression test.

I think most of the spark plug problems can be attributed to someone being a bit hamfisted during the spark plug installation; whether it be a shop or even the guy who installed them new at the factory.
There’s also a process for removing some of them and if that process is not followed then problems can develop.

Some of the spark plug problem is blamed on shallow threads. Consider the fact that lawnmowers, chainsaws, etc also have shallow threads but no reputation for blowing plugs out. Small engine plugs are easy to access whereas many late model car engines have plugs buried deep in a plug well. Plugs should be started with a length of rubber vacuum hose to avoid damaging the threads in a hole that can’t be seen rather than fishing with a socket and long extension.

Good mileage from a truck may be a pipedream and I understsand that. My brother had a 5.7L '88 Silverado that got 25mpg going to arkansas 20 years ago. My 5.0 Mustang got 23mpg with half highway and half city. My wife’s expedition got 20mpg going 70 with AC on. So, what would be the difference between a crown vic and a supercrew f-150 that has 4.6L and NO 4WD?

Thank you fodaddy for the bit on changing rear end ratio. If it would’ve been better and more economical, then Ford would’ve done it to begin with. Thousands of dollars and countless hours went into engineering, so it wouldn’t be wise to go against everything the nerds came up with. :slight_smile:

Btw, it wasn’t a friend the told me he got 24mpg with his 4.6L, it was a guy at a gas station. I have been accused of being too trustworthy. I am a country bumpkin from a small town and tend to trust people in what they say.

MTravler, I will probably die before I ever own a mini-van, but thanks. I have thought about several options. We have four kids. We seat comfortably in my wife’s expedition, in my taurus, we’re a little scrunched. I figured a F-150 supercrew with a benchseat in the front would be as comfortable since it’s like my wife’s expedition but without 3rd row. I am now contemplating an Escape. Then again, I would like to continue the quest to get 250,000 miles or more out of the taurus.

I need to address that EGR system issue promptly. Thank you all SO much for the info so far!!!