when cruising on the freeway, certain areas that are a bit washboard, to heavily washboard cause the front end to get in this sort of shake, gets to be quite rythmic.........scary even. more severe than I could possibly convey here.....lets just say, if you had a drink in the holder, it would hit the headliner.
steering wheel starts to shake.....

certain speeds get it going to worse, say 65-70. at 75, it goes away, but i fear for my wifes safety when she drives it, as her commute is down a 10 mile stretch of the 99 freeway that is full of big rigs, meaning the freeway is horrible, even in a car it's bad. in this truck......OMG.


anyway, i had the stealership check the ball joints, they say they are ok. im going to jack it up this weekend and check them myself.

I have only one other problem up front, but i think that is a wheel bearing......get kind of grinding noise, but never when on throttle accelerating, only when going a constant, light throttle speed. if i let off, it kinda goes away.....


tires have been balanced, and rotated with zero change.


shocks are rancho rs9000x, on setting 7, and tire pressure i have varied from 35front, to 50 front, with no change in this problem.


any suggestions for where else to look??
the problem has been getting worse day by day it seems, started about 3 months ago.
now i get the death wobble in places i never thought were rough surfaces in this same truck.



sorry so long, trying to provide as much info as possible.



thanks!

 

Steering stabilizer maybe is bad. Pull one end off and check it. It should be real stiff through out its range. If you don't have one get one. also bad tierod ends, All this gets exaggerated with bigger than stock rubber, everything wears faster also....

Dick

 

I never ran my diesel Superduties with less than 70 PSI in the front and I never had a front end problem, Air up and see what happens. Good luck finding a fix.

 

Check to see if you have water in one or more of the tires. Some folks are bad about draining air compressors. If you got some air from a poorly maintained compressor recently, you'd be surprised at how much water can get in there and how fast it happens.

I suspect you may have some other problem but this is a chep and easy to check oddball source that would create this problem. Yes, it did happen to me once.

 

Low air pressure in the front tires causes the truck to wobble more. Its most noticable when hitting a blacktop patch that isn't square to the road or a high/low spot from underground pipes that aren't square to the roadway. I keep my tires at 70/80psi front/back and the problem isn't very noticable. Ever damn time the stealership services the truck and rotates the tires they drop the tires to 55/70 and i get the front end wobble back. I know someone is going to complain about keeping the tires that high. But it serves multiple purposes. I haul and tow on the drop of a dime and do not want to keep changing tire pressure. Better gas mileage with the tires inflated. And last but not least... the bouncing/wobble of the front end is mostly gone.

 

The only complaint anybody can have about running the max air pressure in tires is that the vehicle rides a little rougher. Everything else about higher tire pressure is a big plus, you get better mileage , tires run cooler, and you get better handling with heavy loads.
Now I am talking about normal highway conditions. We all know on ice or sand , lower pressure will help. If you have to run 35 PSI in the front of your Superduty to get the ride you want, you bought the wrong vehicle, get an F150 or a Crown Vic.

 

Matt,

I hear ya, the 99 sucks! I'd opt for checking the tierod ends, as noted above. What 6" lift do you have? How long have you had it on the truck? Have you always had it? If not, was the problem worse before or since adding the lift kit?

I would question "airing up" to 70 psi; Wrenchtraveler obviously isn't familiar with SoCal freeways, especially the 99 from Sacto to the Grapevine and I-10 from Palm Springs all the way west to the coast. No offense to him, but people just don't believe it 'til they experience it. I went from 80psi Load E 235/85 tires to Load D 285/75's with 60psi and that helped, too.

Before you jump at spending $$$ on hopeful "fixes", make sure it isn't just the roads that are getting worse and not your suspension. Your '03 PSD should still be in good shape, even with the nasty highways we frequent in these here parts! If you haven't done so already, maybe fiddle with the shock absorber settings and see if you get any relief from the "jack-hammer" effect of our highways!!!

Keep us posted, and me especially either here or via Private Message.

Daryl

side bar: I put the Lord's shackle kit on my (stock suspensioned) 2WD truck in the rear and it seemed to temper the jack-hammer effect a good deal. Just an FYI, though I doubt it'd help since you already have the 6" lift kit....

 

My 84 F250 does the "Death Wobble" REAL BAD around 45MPH.

One of the Radius Arm Bushings is SHOT.

Do 03 F250s still use Radius Arms underneath ??

 

Thanks guys, appreciate the suggestions!

well, to address some of these questions and whatnot...

water in the tires, not likely, but a very good suggestion. air in lines at a body shop is real bad, this is where i aired em up every time.of course, if it built up from the stealership adjusting my pressure every month.hmm.
will need to check.

03's do not have radius arms.



no steering stabilizer, never had one. time to get one................. problem was NOT there the whole time i had the lift tho.......only the last few months. had the lift for about a year, and about 36-38k miles.

i cannot run more than 55 in my tires, but i can try going back up to that. right now i have 40-42.

i do not need a crown vic ride, and i have plenty of experience with how an sd rides thank you very much! this is a new problem, and getting worse.

my lift is a full throttle, 9 leaf front spring, 5" block stacked on the f350 4" block.....yes, i get axle wrap

i checked the ball joints myself this weekend, no probs. same goes for the tie rods......


only conclusion i have, is the rancho's are junk..... must be "wearing out".....but, since i know how they work, i doubt it is even possible, other than seals, and they are not leaking.
my solution thus far, i ordered bilstien shocks valved for this beast for the front. summit said they do not have a listing for a 6" lift rear. my searches here gave me a part number, but the bilstien catalog states they are for 0-2" lift for the rears..........anyone have a good part number????


i am GOING to order a steering stabalizer..........will prolly go with a dual. any suggestions?


thanks again!!!!!!!!!!!!!!!!!!

 

Just a FYI...
I ordered the Heavy Duty Bilsteins for my 250 SD and found out Bilstein calls everything heavy duty, got the wrong ones.
They make "light duty" ones for the 250 they still call heavy duty.
Sent 'em back to be replaced with the correct ones.
You want part number 2818 & 2819.
The 2489 & 2284 (250 LD) have the wrong type mounts, won't work at all.

I'm interested in the steering stab, I need one too.
Starting a thread on it.

 

On the comment above about my not being familiar with South Cal highways, over the years I have pulled a 5th Wheel or hauled a slide in Camper down I-5 from the Canadian border to the Mexican border over 9 times and I know the clickety-clack of concrete highways. One thing all Canadians appreciate is the fact that your Freeways have no traffic lights although we have sat in gridlocks in Seattle for hours. Our lousy Trans Canada highway has 5 Traffic Light Intersections in my home town alone and what we call Freeways up here you guys would call goat trails. We also get many frost heaves in the spring months so I know all about rough roads.
I think the Bilstein shocks might be the way to go as I find my 05 coil spring front end to be a little rougher than my previous 3 Superduty 4X4s with the leaf spring front end. I'm keeping my tires at 70 pounds. I would never go lower than 60 with the E rated tires on an F350 and I found very little difference in ride at 60 PSI.

 

Get under the truck and look up at the steering box where the pittman arm connects to the steering shaft. Have someone turn the steering wheel back and forth slowly and check for play in the steering shaft.

Just a small amount of play can cause the problem you are having, as the small looseness is magnified by the time it gets to the wheel.

There is a lot of stress at the shafts, and they wear and get some play long before they ever leak.

A steering stabilizer will help a lot, especially a dual shock. Also, setting your toe at straight ahead to maybe 1/64 out. This should help keep the wobbles out.

What happens with too much toe in is that when the tire lifts off the ground on a bump, it comes down and is pointed inward very slighty. The edge of the tread catches and bounces up, causing the load pressure to transfer to the other side, which also has a slight toe in. This same reaction now happens on this side, causing the weight to shift back to the other side, and on and on, until you slow down enough for the wobble to quit.

When the tires are aired up high, there is not as much sidewall flex for tire to catch, roll under, and then bounce back.

I hope this makes sense, it's hard to fully explain. I have many years experience with straight axle trucks, and the toe setting helps when things start to wear.

Here is a link to a steering box, frame stiffening repair that seems to help the Dodge boys with the same problem.

http://www.solidsteel.ca/DSS.htm

 

thanks yourbird, that made perfect sense.......


Believe it or not, i diagnose suspension problems on a dailey basis, just not trucks usually......


the toe out idea is a very good one.

I am still looking for a dual stabalizer setup for the truck to install when i do the front bilstiens. I will also air them up to max, they are set low not for ride comfort really, but for tire wear, since they are 12" wide on a 7" wheel (stock wheel, 315/75 tire).



once again, thanks!

 

Got a new '02 F250 2wd for a work truck (fleet vehicle).A few times I'd hit a bump,and it would dribble like an out o control basketball.HAd to dang near stop and start over.Took it to our shop guys.They looked at each other and laughed.Went to the parts rack and grabbed an add on steering stabilizer kit.Said they had been getting lots of complaints.Seemed to have solved it.I got a '05,PSD crew 4X4 last month,and the front sometimes gets to wobbling.And this one's NOT the company's.Dave

 

I would suggest replacing the bushings in the track bar,or the whole bar it's self.
This is the bar that keeps the axle from moving side to side. The bushings may feel
OK but I can almost say for sure that is your problem. I am a auto tech and deal
with the "Death shake" on a regular basis!