Here whats messed up. Balljoints, tie rods, drag link, all related steering components are new and the front end has been aligned. tires are new as well.

 

If you lift the front end up and grab to top and bottom of the tires and try to move, is there any "free play" or slop??

 

No play at all in front end.

 

I had a bad u-joint a while back and it caused the truck to shake. MAybe the problem is not in the front?? Just throwing ideas out there....

 

Just got a call from my friend. They are going to go for a roadtest while someone keeps and eye on thefront wheels. My concern is that it comes and goes. She just told me it was a brand new paved road no bumps no brake input and it started to shake.

 

Just found out last night the truck does not have a steering stabilizer on it. Also during a 20 mile road test the truck never exhibited the shake. My friend told me it started when there were to round bails of hay in the bed. Unfortunately the round bails were not in the bed when I test drove the truck. This is some really weird stuff. Any other ideas?

 

2 round bales isn't really alot(for a Ford), but it sounds like it may just need some new heavy duty shock absorbers. He probably just hit a little bump or pothole & the tire bounced a little too much. Adding a steering damper also will keep the steering wheel from "locking up" when you get the tire bounce.

Just for ****s & giggles, you could roll a couple bales in it & test drive. When it bounces, stop & drop the front tire pressures down to 30-40psi. Try to duplicate it again. If it doesn't do it at all or does it alot less, you should just need new shocks.

 

Commonly known as "the death wobble", this is a malady that plagues many straight axle 4x4 trucks. If you'll search this forum (and others), you'll find lots and lots of discussion about it (I've even seen videos on you tube), but no single absolute definitive cause. I think it's usually mostly a combination of a little wear here and there, but as others have said, the single biggest help seems to be a new steering stabilizer. That and rotating and balancing the tires resolved it for me. In this case, I'd add a steering stabilizer since there's not one present - it's relatively cheap and easy and it can't hurt anything. Another often overlooked factor is proper inflation of the front tires - just a little underinflation can contribute to the shake tremendously. I was running 65 lbs. in my fronts, when we balanced and rotated we brought them up to 75 and haven't had any problem since. You might try rebalancing those new tires, could even be one of them's a little out of round...

Hope some of this helps.


On edit; I also agree with what DLP posted while I was typing - a new set of shocks might help, too.
I first noticed mine shaking with a load too (loaded 24' gooseneck stock trailer), but as it got worse, it would do it without a load as well.

 

Have the truck inspected at a "proffesional" alignment shop.

 

You guys are great!!!! Lots of excellent input, really do appreciate it. I am going to keep plugging away at this rig and keep you guys posted. Real happy to see there are still some good people in this crazy world we live in. Thanks again for all of your responses.

 

I had a very bad vibration in the front end that was linked to the wheel hub. The front axle shaft (4x4) hub bearing was bad. Every now and then the whole front would shake very violently. You can verify it this is the issue by grabbing the axle at the u-joint and trying to move it up/down or side to side. I found that if I kept the axle turning by manually locking the 4x4 hub it would keep the axle turning and not shake. Later I just used ty-wire to keep the hub locked in position untill I could put a new hub on.

 

you know I have the same problem with a two wheel drive unit 99 350 drw
I installed a new stabilizer two to three weeks later shake is back. haven't replaced shocks yet. Shake usually happens at or around 35 to 40 miles per hour when shake happens I let it slow down at 30mph it stops. roads here are paved but a little pothole ridden. any help will be stop me from going bald
thanks

 

Saxjet, That sounds like out of balance tires to me. Does it go away at a higher speed, or just get worse / same?

 

Ditto!!!!.

 

Ok.... Dealing with the same issue....

I found mine today....

Belive it or not it's the u joints.....

you stated that you just replaced them.... well guess what my friend, you did NOT mark the drive shaft, now the shaft is out of balance.......

it will do this at diffrent speeds, then it will clear up..... RIGHT ?

if so, then if it's a 4 X 4, and if your still not convinced, remove the drive shift, put it in 4 wheel drv, and try to dupelacte the issue, if ya cant,,,,, BINGO.

Best of luck