I have a 97 F250 CC 4x4 with 7.5 460 w/103k miles. I went to pick up my camper from storage yesterday and it felt like I was towing 20k lbs. My camper is about 6k lbs. The truck seems to run fine without a load. I have only had the truck for a few months and this was the first time towing with it. I had it floored on the highway and topped out at 60 and the slightest incline would drop my speed drastically. There was a little rattling sound coming from the engine that sounded kind of like a vehicle that wants to keep running after shutting off the ignition (dieseling?). I have no idea what could be causing the power loss. Could it be as simple as a tune-up? Any help would be appreciated.

 

Sounds like you need to check your ignition timing. Got a timing light? Unplug the spout connector and take a look.

 

OK.. but what is the rest of the combo, what trans, what axle gearing, and what size tires are on it?

What did you use to pull the trailer before getting this truck?

 

it's a 5-speed 285/75R16 tires not sure what gear ratio it has. Where can I find it?

Had an 04 F250 2wd automatic w/5.4 before. It didn't feel like I was towing anything with my trailer behind that truck that's why it seemed strange to me having the 460 towing it and being so bogged down

I do not have a timing light. I've never checked timing before.

 

I would be suspicious of a plugged catalytic converter. My 89 460 5 speed seemed ok until I hooked a car trailer up and headed to the drag races. It was choking and bogging under load. I struggled to get over 50 mph. I was getting pinging and a noise back through the air diverter valve. Opened up the exhaust with dual flow masters and I gained mileage and power. Of course checking the timing etc shouldn't be overlooked either

 

Look for the Axle code on the door jamb sticker:

Bottom right side of the photo. This example is Axle code 19

Code 19 = 3.55 gear ratio

Axle Code chart: Ford Axle Code Chart - Ford Trucks

 

Find the axle code on the drivers door pillar calibration decal and post it up. Do you know what gearing the 04 had?

It is likely your '97 has some issues so I'm just covering bases here to get an idea of what kind of performance you should be seeing. If your truck has a factory original exhaust on it you may have a clogged cat, or it may have a weak fuel pump so you will need to check fuel pressure at idle and with vacuum removed from the regulator. And you will want to check to see if the air horns have been removed from the intake tubes, these horns were a dubious attempt at reducing intake noise that ends up being a serious choke point so you will want to cut them out if they haven't been removed already.

 

I just had headers with 3" y-pipe and single 3" pipe through a magnaflow muffler installed. Got rid of the cat all together.

Axle code 39 on my sticker 3.55 on the chart

 

Well that is one thing eliminated, now you need to check fuel pressure and timing.

Well that's not a great towing ratio but the 460 should be able to deal with it better than a smaller motor.

 

Not to state the obvious..
your 01 most likley had 4.10s and was 260hp/350tq
your 96 is only 245hp/400tq and the 3.55 gears KILL it

 

It should still tow 10k lbs regardless. My camper is 1/2 ton towable at 6000 lbs.

Topping out at 60 mph and slowing to 55 on a slight incline tells me there's definitely something wrong. I will get the timing and fuel pressure checked out and I'm also going to do plugs and wires while I'm at it

 

Do you still have an O2 sensor?

 

Don't neglect to check and adjust the timing. With the headers and open exhaust you likely can bump it up a degree or two. Mine likes a little more timing. What gear are you in while doing 60? Mine pulls fairly heavy loads in fourth gear while maintaining about 3,000 rpm at about 60mph. If your in fifth you're likely dipping below the ideal power band. a good tunup is always a good starting point

 

I do have the O2 sensor installed. Not throwing any codes on the dash other than ABS and all gauges read normal other than speedo jumps around until I hit 45 mph. I was in 5th gear when I topped out at 60. I was told my trailer wasn't heavy enough to need to stay out of O/D. I do not have a tachometer to read the RPM's. Been meaning to get one

 

What camper do you have?