i love my ford

i have a 1985 f150 with 208,000 miles on it, and i have a question.
when i hit 45 mph my whole truck rattles and it has gotten worse.now its from 45 mph up to 60 mph and i cant figure out what is wrong. it has new rotors and front brake pads. what it feels like is that the rattle is coming from the center of my truck. please help

Hysteric

probably alignment. will cost upwards of $120 or so to fix, depending on the shop

FordMan23

Mine was doin the same...got it aligned and it seems to be just fine.

SinCityFX4

Possibly Alignment.
How are the tires?
What do your ball joints look like?

8thgenf150fan

It is probably an alignment or tire balance issue.

loon

had a van years ago and couldnt figure out why the thing shook so bad,
ended up it was a hanger bearing...

Ranger2F150

Since you stated the vibraton is from 45-60 mph check your drive shaft probably needs rear ujoint replaced.

transmaster

With a Twin I Beam front end, either the two wheel drive version or the 4X4 version you usually don't get virbration you get poor directional stability. In otherwords the front end wonders, especially when you get on uneven road surfaces. Listen for knocking especially in the 4X4 version this is often a tell-tale for the condition of the bushings. This is also true if you ball joints are bad. To tell the state of the front end take a look at the tires. If you have bad radius arm, and, or worn axle bushings you will have cupping on the inside (see the illustration below) of your front tires and you can have vibration from out of balance tires. However the type of vibration you describe does sound like something in the drive shaft. Put the truck in neutral with some one help push the truck back and forth just enough to take all of the pressure off the drive line chock it up so you don't get run over and crawl under and move the drive shaft and check to see if your UJ are loose, if you have a carrier bearing make sure it is turning smooth. Check the drive shaft for dents, and inspect the shaft to make sure the little tabs spot welded on to balance it have not be knocked off. If it turns out you need to replace the drive shaft, very unlikely, there are aftermarket shafts that are much stronger and also have much less weight.