[giddyup]

I just bought a 1993 Bronco with a 351. Great truck and I like this website.

My truck starts shaking at 65-70 on the highway. When I bought it it had very worn and cracked tires. I figured that was the problem. I had some half worn 31x10.5 general grabbers. I had those put on and balanced and the same thing. I haven't had an alignment yet, but it is next.
I don't have a steering stabilizer. It has dual rancho shocks up front. Doesn't look like anything is bent and this truck has seen little to no 4 wheeling. The driveshaft looks to be OK and U-joints look OK.

I am not very familiar with these suspensions. Is there anything else that could cause the vibration

 

[abra]

check your ideler arm, bushings and also driveshaft at the eyes.

 

[broncoguy1993]

This might sounds a little scary but go faster and see if the shaking drops off. On my 1993 with the 351 I get a vibration from 48ish to 52ish. Before and after its fine. It started after the 4" lift though. Actully at 70 mph my Bronco runs really nice.
-Luke-

 

[1clean5.8]

how many Weights did they have to put on your wheels ? mine stops shaking @ 75 but your wheels could be slightly bent

 

[waltman]

What kind of rims do you have, steel or aluminum alloy?
Eye balling your drive shaft wont tell you if it is out of balance. Are the u-joints in your drive shaft greaseable? If not you may have to replace them.

 

[Million$dragon]

Mine used to shake on the freeway like that....but not at lower speeds. I replaced my radius arm brackets and bushings. And I haven't felt the problem since and my steering wheel is in the 12:00 position now instead of the 11:00 position. So you might want to take a look at those. It's pretty easy to see if they are bad.

 

[ToddACimer]

are your u-joints lined up on the drive shaft?

 

[waltman]

are your u-joints lined up on the drive shaft?

That's a good question.

 

[ToddACimer]

That's a good question.

I learned that one from experience

 

[giddyup]

Thanks for the suggestions. I will check that stuff tomorrow and update.

 

[WJR]

Sorry to but in on the thread, but I am having the same problem. Also, after taking about a 45 minute trip on the highway, I have a strange noise on the front driver side. On a smooth road, I do not hear a noise, but on a bumpy road it sounds (to me) like the TTB is not attached to something or something is creaking back and forth.

I really am a complete mechanical moron and usually have to take the Bronco to a shop for anything. How can I tell if my ball joints are bad or if it is the radius arms that are bad? The steering is loose and the shop told me that they could not get a good alignment on it. The steering wheel is at 11:00 as someone else mentioned. I have a new steering box to get installed, but have not had time/money to take it somewhere.

Since I bought the Bronco I put new 31 BFG ATs on it, new shocks, and had the bearings greased and packed.

I also had new front brake pads, rotors, and cables and new shoes on the back. By the way, the shop that did all of this for me told me that my suspension looked good. I asked them several times and got the same answer.

Please help!!!

WJR

 

[Bronco Rob]

Mine is at 11:00, loose steering and it's my ball joints. Just haven't had the time or $$ to replace them.

It sounds like that shop wants to be honest with you, at least they aren't replacing good parts. Go tell them exactly what you told us and see if they will check your ball joints and your steering.

Your suspension being good doesn't necessarily mean that your steering is good.

 

[WJR]

Thanks Bronco Rob. I guess that is what I am going to do.

WJR

 

[giddyup]

So, I checked everything and it all looks good. I'm going tomorrow to get an alignment and see if it aligns OK. It seems to start shaking at 65 and gets worse at 70 and stays about the same to 80. Thats what my speedo goes to. It does seem to get worse around gradual turns on the highway.

I also noticed there were far too many weights used to balance the wheels and they are all on the inside. Two of them have 3 weights. I'm not sure that they are supposed to have that many. I am going to have the tires balanced again.