I bought a new 4.6L F-150 in '97. It only has 60K miles on it, but I would dare say it's one of the best engines I've ever had in a full sized truck. Last year, I had a leaky fuel injector, but that was the only problem I've ever had.

Under the right conditions, I've had exceptional gas mileage. With the OEM Goodyear Wrangler AP tires, 89 octane fuel, correct weight 5W30 oil and keeping RPM's under 2K when accelerating, I get 18 MPG around town and 22 on the highway with no load. With a 2000 pound load, I was getting about 16 MPG on the highway.

If use 10W30, gas mileage drops. If I use 87 octane, gas mileage sucks. If I romp on the gas and go over 2500 RPMs, mileage is horrible. When I swapped out the OEM tires for something that had traction, I lost 2 MPG.

 

I've been very happy with my 4.6. I've bolted on some power adders and it responds nicely.

The 4.6 feels less torquey than the 5.4 and the power curve is higher in the rpm band but you can rev the stink out of it and still be "in" the power curve. I think the 5-speed works well with the 4.6, even though the Mazda transmission Ford used in these trucks kind of sucks. With the 5-speed you can bring the rpms up enough so that the next gear your in the meat of the power curve. I think the auto would shift too soon.

The 5.4 will "feel" more powerful because of it's torque and where it comes on. The 4.6 isn't so bad either. If you feel like you don't have enough power there are a few things that you can do to bring it up a notch or two. I would reccomend at least a chip/tuner to bump up that rev limiter and to take care of some of Fords "designed for the masses" tuning.

Good luck!

 

Be careful about the gear ratio. I would ask before you buy. I got stuck with 3.31's in my 2001 4x4.

 

The 4.6L is so good, I have one in a Mustang. The other one has over 210,000 miles on it. I also had one in another F150, but this was during the HG leak era for Ford (2001).

 

There is nothing new about the 4.6. It's a very robust engine that's been around long enough to get the kinks worked out.

Assuming the oil changes and other regular maintenance was kept up, the 4.6 could last you 250k or more miles.

 

Had mine for just over 90K without a problem at all, then...

The theory was a bad head gasket that allowed radiator coolant into a couple of the cylinders. Their (speculative) vain attempt to compress liquid failed miserabley and ended up with me getting a new engine. The failure was sudden and without warning.

I'm not going to say it's a bad engine, but it's not the greatest thing since sliced bread. I had a Nissan 4 cyl. years ago and I beat the livin' $h!t out of that thing and it wouldn't falter. I went to the Ford because I wanted some comfort and style along with the increased power of the V8. I do like the truck alot...and plan to keep it for as long as it runs well...but there are occasionally times when I would have liked to have kept my Nissan (rust bucket, rattle trap that it was).

All in all, I like my 4.6L and the rest of the truck as well.

 

I just bought my first 4.6l in a 2002 screw. To be quite honest this thing has surprised me. I wanted the 5.4l but had to take what i could find in the 4.6. I would easily buy the 4.6l again. I am only getting about 15 highway at 75 mph, but this engine hauls. I have a passing gear that is unbelievable. This truck has plenty of power. The engine as far as i am concerned it great. I think i would actually prefer the 4.6l now over the 5.4l (just for gas mileage alone)

 

159,300 miles and this engine is running so good its scary. I have to admit I run it hard. Have towed 3-4000 miles a year. Mine is a 97. Had to replace the trans last year but the engine is still strong.

 

Check out this post to see how many are in the 100,000 mile club, many with more then 200,000 miles.

https://www.f150online.com/forums/sh...hreadid=100041

 

except some stinky head torque specs/gaskets they were using on some of the trucks during the 2000/2001 production year. Plus some EGR valve defects, etc. The engine block is fine. Heads sometimes are defective. There's a TSB out on the heads, though.

 

My buddy had a 86 Nissan hardbody 4x4 with the 4 cylinder and that thing had over 300,000 on it and it still had the original clutch. We flipped it twice, had the engine compartment under water a couple times, and beat the living holy s*it running itup to
5,000 rpms all the time. Ran strong as hell and never puffed any smoke. He drove it 30 miles round trip every day to school. Later sold it for 500 dollars and it still ran like a sewing machine. Wish he still had it....

 

"a Sea Foam treatment ???" Ok I have to ask what this is, what it does, what it costs and where you get it done or can you do it yourself ?? I have a 4.6 v8 that likes gas...can this help it give better mileage ??

 

'90 F-150 XLT Supercab . . . .
232,565 . . .
original transmission
original engine


I'm waiting to put it to rest

 

Basic rundown - go to your local parts store and pick up a can of Sea Foam for 5 or 6 bucks. Disconnect the vacuum hose from your brake booster while your truck is running, then stick that hose into to the can of Sea Foam so that it sucks it into the intake manifold. Immediately shut the truck off and let it sit for an hour or so. Come back and start it up, then let it run for awhile until all the smoke stops coming out of the tailpipe. Then you're done.

Basically the Sea Foam will help to clean up any carbon buildup inside of the manifold and ontop of the pistons that might be reducing your fuel mileage and power. Like I said, my truck responded right away.

If you want more info do a search for "Sea Foam".

 

Ditto to what everyone else has said. I have the 4.6 in my 97 F-150 EC 4x4 with 3.55LS and auto transmission. Engine has simply been bulletproof. No problems to speak of.

It has enough power for me, has a good passing gear on the highway, is reliable, burns no oil between changes and quite simply, it gets the job done. I would have no problems recommending the 4.6 unless you need the extra power of the 5.4 for towing. I usually get around 14 mpg in town and 17-18 on the highway. I have about 125,000 km on mine.