I know it's been asked a lot, and I have read a bunch of threads on MPG. But I wanted to make sure I don't have any issues with my new / used truck I purchased about a month ago.

It's a 95 F350 4x4 crew cab long bed. It is 100% bone stock and has 150K miles on it.

I have a very light foot in town and on the highway and currently I am getting about 6.5 to 7 mpg in town (empty), and about 7 mpg on the highway with a 2600 lbs camper and about 2000 lbs trailer keeping it under 60mph.

Haven't checked it on the highway empty yet since I don't really travel without the camper and trailer.

Since I purchased the truck a month ago I have done the following:

Plugs
Wires
Cap
Rotor
K&N Air filter
Master Cylinder
Calipers
Pads

2 years ago it had a new distributor, power steering pump, and radiator put in it. I also flushed the coolant system out a few weeks ago. Most of the stuff is factory Motorcraft.

Truck runs excellent, but seems to be below average on MPG from all the threads I have read. Also, when towing my camper, the truck seems to struggle a bit. Going up gradual hills hauling under 5000 lbs, it wants to quickly down shift and rev pretty high. Can barely keep it at 55 with my foot really into it.

Even with the truck empty, it doesn't feel very peppy. I have been driving diesels for the last 16 years, 7.3l and the 6.0l with the same towing setup. And I have to admit, this particular 460 has somewhat disappointed me. Not the MPG (I know it is going to drink fuel), but the performance in general. If this is really how the 460 performs, I would take the diesel over it any day. My diesels would do the same drive towing the same thing and not even break a sweat compared to the 460 I now have. But from all the great comments and happy 460 owners I though I would give it a try.

I only bring up the low MPG in case there may be an issue with the motor which would also cause lack in power. I was expecting to get between 8 and 10 in town and towing. But I really feel I should be getting more power from everything I have read. Especially all the gas vs diesel comments. Cause right now in my mind, my 460 isn't even in the same class as the diesel.

If anyone has any ideas or comments, please let me know. Thanks!

 

That sounds about right. In town I get terrible mileage (about 6) and on the highway the best I've ever gotten is 11.8 but I normally get around 10.5.

 

Thanks! That's good to know that I am about right on the mileage. Now I won't have to think about that anymore.

As far as the power. I have seen so many debates on how gas is better than diesel, and visa versa. Right now I just don't see how there is even any comparison from gas to diesel. The diesel is far superior in performance to my 460. I have owned both the 7.3l and 6.0l and its like comparing apples with oranges to the 460.

Do any others who have owned both the 460 and diesels feel the same way? Or is my 460 just down on power for some reason.

I wouldn't feel comfortable putting any more weight behind my 460. A 2600 lbs camper and 2000 lbs trailer really strained this motor on the smallest hills.

I would tow the same 2600 lbs camper and a 6000 lbs boat on my diesel and would have to keep my eye on the speedo to keep it under 65. I couldn't even imagine doing this with the 460.

Anyway, I'm still very happy with the truck. And it does exactly what I need it to do.

 

Well something definitely doesn't sound right. I just picked up a similar truck as yours but it's a 1990 with a 5-speed manual and 3.55 gears in the differentials. I really wanted the 7.3 diesel (last of the non-computerized motors ever made), but I have to say that my 460 pulls like a diesel - I lug the heck out of it and RPMs are anywhere from 1500 to 2000 90% of the time. And I've been averaging 11mpg with mine, but I do accelerate very slowly and coast as much as possible.

First, since it sounds like you have the E4OD automatic, do you know for sure that the torque converter is locking up? You can tell by watching the tach, it will drop once when converter locks up, and then a second time when it shifts from D to OD.

Do you know what your axle ratio is, and what size of tires are you running? These things will definitely affect the mileage.

How about front-end alignment? When I got my truck, it crabbed down the road about 2" to the left side. Did an eyeball alignment down the sides of the tires (amazingly you can do a pretty good job of setting the toe-in this way if your front end parts and bearings are all tight) and the front two wheels were toed (sp? that doesn't look right) in probably about 1/4". I can't believe that the previous owner drove it that way, but it certainly had to affect the mileage. Low tire pressures and sticking/dragging brakes are something to check as well.

Then, I'd start with a compression check of your engine just to see what kind of condition it's in (one never knows, 150K miles is getting up there esp. if it hasn't been treated well). If that checks out OK, I'd look at the spark plugs and exhaust to see if it's running rich (a shop can also check with an exhaust gas analyzer). At that mileage and age, it wouldn't be a bad idea to pull the injectors and have them checked/cleaned - the nozzles can gunk up and the filter screens can get clogged, leading to poor spray patterns. I'd also check your manifold vacuum.

The only other things that come to mind which could cause low fuel mileage are: 1) if the computer is not going into closed-loop mode (using the O2 sensor to determine how much fuel to inject), and/or 2) computer thinks engine is cold and is keeping the mixture extra-rich (is usually a defective coolant temperature sensor). You will need a full-feature OBD I scantool (not one of the sub-$100 ones) in order to determine this, or a shop can do it. Exhaust gas analysis would quickly pick up on this as well.

I would spend money first on good diagnosis before throwing any more parts at it. My neighbor just paid $1900 to a local chain-store shop for a fricking missfire code on his Windstar. I looked at his invoice, and they threw every part under the hood at it (they would have thrown a kitchen sink in there too but I guess it wouldn't fit). It makes my blood boil - a good mechanic probably could have rectified his problem for under $500 (NO IDEA what actually fixed the real problem). I try to help him out when I have time but he tends to take his cars to random shops instead.

 

Thanks for the ideas to try.

As far as the E4OD, I drove with one for 10 years on my 96 7.3l and the 460 seems to be shifting exactly the same. But you mention the converter should lock up, would this be on the 3rd shift front a stand still, then at about 40mph it shifts again which should be going into overdrive (very light on the pedal). Does this sound about right?

I'm running a 305-70-16 tire (33"). The speedo is dead on but I think the tires are a bit worn and closer to 32" (stock was 31.7").

I have 4.10 gears with a limited slip. Door tag and axle tag both matched. This is probably why I am spinning about 2000rpm at 65mph. But now that I know this (just checked it out) I would expect even more pep out of this motor having those gears.

Front end alignment looked pretty good. I did just installed new tie rod ends and center links. I took some accurate measurement of the stock ones before I removed them, then counted turns and re-installed the new ones exactly the same. When I re-measured the new ones they were spot on. I should measure my toe in and see where it is at. Though the truck does track nicely and doesn't pull left or right.

Tire pressure is right on. Though brakes are an issue I am fighting with. With the front tires off the ground and the wheels off, the rotors are very hard to turn. Need to use two hands to turn them. I've posted another thread with this in detail, but I have replaced all the components up front except for the rotors and brackets (master, calipers, hoses, booster, complete flush of fluid front and back) and the brakes still drag. It is a mechanical thing because the calipers don't even fit properly with new pads. With no hoses connected and the caliper simply bolted on with new pads, they drag! I've tried 3 calipers and two different sets of pads with the same results. Anyway, this is something I am still working on and may be a cause. Though it is not too bad. With the truck in drive and at a standstill, I can let off the brake and it starts to move pretty easily. So I don't think it is robbing any power.

I will do a compression check and check my manifold vacuum. Something I should have done when I installed the new plugs. I did see some vacuum hoses that looked pretty stiff, and even one that looked as it was repaired with some heat shrink. Maybe I have a small vacuum leak. Not sure if this would cause some of my issues. Don't think the distributor has a vacuum advance on it, can't remember.

The truck runs really clean. Just had it smogged and it passed with extremely low emissions. Also I notice in the mornings I get water drops from the exhaust which is a good sign that it is not running rich. Exhaust also looks pretty clean (no build up), and the old plugs looked OK, just old and worn out.

I did run some Injector cleaner on my first full fill up. I still have half a bottle and will probably run it again.

The truck idles great, probably smoother than my diesel. and it doesn't miss or anything like that.

I'll check a few of the things you recommend and try and figure out my brake issue. It is tough because I don't really have anything to compare the power with except my latest 6.0l, and that has almost 100hp more so it is not really a fair comparison! All I can do is make sure everything checks out then I'll know that is what I can expect.

Thanks.

 

Somethings not right. I bought mine new in 89 and still runs as day 1... strong! I do have the 5 speed but same gearing and run 35's. Ill pull my 5000lb boat without issue other than the fuel. I drove tow trucks with the 6.9 and non turbo 7.3's years ago, and can say the 460 out pulls the 6.9 and was on par with the 7.3 for the most part. They both had their +/- 's Power is not the weak link on a 460. I had a bad egr that was making it run lean and cut power. Worth a look

 

That's kind of what I was expecting when I bought it. Seems like it should pull much stronger that it did. I was surprised going up some not so steep hills on the freeway and my speed was dropping down to 45mph, and I had to almost floor it to keep it at 55mph with under 5000 lbs behind it.

I'm making a list of the things I need to check such as the compression, vacuum, and egr valve.

Another thing I think I heard was a bit of pinging when when I was really pushing it. Though the timing was at 10 deg BTDC when they did the smog check about a month ago.

 

If the computer is getting signal from the knock sensor it will pull timing and kill performance and mileage. Id check for vacuum leaks

 

Hmm. That could be it. Like I had mentioned, the vacuum lines looked pretty old and some had been repaired with heat shrink.

And I am sure it was pinging. Didn't know the computer had a sensor for this. Could be a reason why I was struggling so hard up those small hills.

Terry

 

Check all the caps on the vacuum tree in the center of the intake manifold too. A small leak will not really show any signs but will really throw things for a loop when you make it start workin!

 

No one has suggested a stopped up cat converter yet. Wouldn't that keep your smog check low and be robbing lots of power? I'm fairly new to 460s but i've read this is a common problem on them. Mine is very strong, 250k and has pulled a 10K lb camper all of it's life and it still gets 10 or so. I just removed my cat only to find out that it wasn't plugged up, i did this mostly to see if mpg might improve, but i'm doubting it now.

 

Never thought of that. Would be pretty difficult to check. I could run a fish tape up through the tailpipe and see if it goes through freely. Though when the cats start to rust out, don't they just blow all that stuff out?

Or would it jam up and actually clog the exhaust?

Another thing I'll put on my list to check.

Thanks.

Terry

 

I've heard they will clog, especially on Ford 460s, but I dont know of any way to check so I just bit the bullet and removed mine. Van has 250k. I'm really curious to see what solves your problem. Wierd, 460s are usually STRONG!!!

 

460s don't have knock sensors. Although the distributor is set to 10BTDC, the ECU will advance the timing from this setting as long as the SPOUT plug has been replaced. Not much power if nobody put it back though. I believe the way to check for plugged cats is to remove an O2 sensor and check the pressure.

 

I have a 94 460 that I pull a 12K 5th wheel with. I have taken it over the Smokie Mountains with the camper and it slowed it down but it pulled over as it should. I found a station that had a smoke machine that we used to check for vacuum leaks, I think it is the best way to find small leaks. Also added Banks headers and complete exhaust which really helped performance.