Today my 79 started to shack side to side, like a wheel was about to come off when I started brakeing on the hwy. I let off the brake, and it continued to do it until I was down to 25mph or so. Its done this three times, but all at different times. I am going to check front wheel bearings, and the steering box is loose, but anyone know what it might be? Need to get this fixed. Thanks.

 

warped rotors comes to mind

 

I think you hit the Nail on the head Tina It could also be a Bad Rag steering joint/coupler just above the steering gear box, I would look for bad tie rod ends, also check your tires, put the front tires on the rear and the rear tires on the front if you dont find anything mechanical wrong, and drive it, it could be a bad tire, hope that helps, Chellie

 

also a wheel weight could have come off of the front wheels

 

After checking everything suggested, look very carefully at the frame near the steering box. I have seen a few that were broken. Usually the steering just starts to feel sloppy and then it gets worse, sometimes pretty quickly.

 

Check the track bar bushings, if they are bad it will let the axle shift side to side and cause the condition you are describing. With the wheels on the ground have someone rock the steering wheel side to side and watch the steering and suspension parts for movement.

 

Thats exactly what I was going to post.

 

Sounds like the potential beginning of death wobble. And if it is, could be anywhere in the steering linkage or front suspension. Lift the vehicle, and have a buddy move the steering wheel slowly side to side back and forth until you're content you don't see any slop or binding. Then have him do the same thing but in a jerky fashion to see if impact plays a role. My guess is you'll see something moving or loose that shouldn't be. Also check your shock mounts, I had one loosen and caused the DW. Good luck.

 

I'm not so sure he's in the beginning of DW, I think he may be already there.
I've owned my '78 F150 nearly thirty years now, and I've had this exact same thing happen to me once. It took me quite a while to find it, and many parts were changed that probably didn't need to be. On my truck, it turned out to be the bracket that bolts to the frame (on the outside) directly between the power steering gear box and left front coil spring. This bracket is the mount for the bar that runs to the right side of the front axle and bolts to it next to the right spring. Sorry, but I don't the proper Ford terminology for that suspension component.
On my truck, that bracket being loose caused exactly what you described. It had been loose long enough to enlarge the holes, and I had to remove the bracket, drill the holes to the next size, and install new bolts.

I'm not saying that is the problem with your truck, and a previous poster already said to look for cracks in this very same area. Make sure the bolts are tight on the steering gearbox as well. I highly doubt it is your rotors, and as a previous poster said, check your rag joint too. I ripped one of those up many moons ago, and now keep a very close eye on that component as well.
Jim

 

Ehhh...I said beginning because it's only happened 3 times. I've known rigs that can't hit a bump/pot hole/RR track without the steering wheel almost breaking their thumbs, and then having to come to a complete stop. Definitely dumb...but that's why I said this seems to be in the beginning stages, cuz to this point seems relatively minor.

 

I think anyone that has had a truck do this will agree that just once is one too many times. I've not known anyone who had a truck go into DW classify this condition as 'minor', and I would guess the OP would agree.

 

Sounds about right guys. It could have broken a thumb for sure if i was holding the wheel wrong. I knew this was gonna happen sooner than later. I have quite a bit of play in the wheel. Doesn't L and L make a replacement column for our trucks. Also I know that the box needs rebuilt, and thinking of sending it to the guy outta washington named "RED" I think. You need a light hand to drive it for sure. Well my worries are what if it did it during winter, or worse when my wife needs it for the 4wd.

 

I didn't say it wasn't scary...but being that it's only happened 3 times to this point, I don't think any of the parts are to the point of catastrophic failure. That doesn't mean I'd push my luck and keep going with it, it should definitely be fixed...but it could still be alot worse.

 

also check the steering gear box adjustment, it could be loose, loosen the lock nut and back it out, hold the nut and turn the screw in untill it bottoms out, back out 1/2 turn, and retighten the lock nut, check to see how many turns it took to bottom out the adjusting screw, my steering gear box on my 1985 F-250 was way out of adjustment, i noticed that when i drove it home, a quick adjustment, and its all better now also, look to see if a hyd shock dampner is avalible for your truck, its basicly a shock absorber that attaches to your steering linkage, I dont know if your truck has twin I beams or not, if it does, use heavy duty front Gas Shock Absorbers, that will also help to keep your front tires from cupping real bad, Just my 2 cents worth, Take care, Chellie