Ah yes, the vibration topic again. So here is the run down.

For Reference, Its a 1996 F250 CCSB, 7.3, 333K Miles, TTB front end, no lift. In JAN 2022, installed new 4600s and new 285s Open Country Tires.

Surprisingly didnt have a vibration that was worth chasing before March 2022- actually drove pretty good all things considering. Well, Went on a 300mile round trip and the first 150miles, normal. Parked for a few hours and immediately getting back on the road and on the highway, very noticeable vibration between 60-70mpg that wasnt there before. But the steering wheel wasnt vibrating, more like the cab. It was annoying but chalked it up to the TTB and needing to replace the pivot bushing and all others in the front suspension bushings. Ive put a camera on the frame pointing at the wheels, pitman arm, suspension and nothing looks like a mini death wobble or shocks.

Replaced the TTB D50 Ball joints and axle U joints back the following week... Same Vibration.

Fast Forward to today:

In June, I Completely rebuilt a 04 Superduty D60 (all new seals, bearings, BJs, UJoints, Sway bar bushings,...) up front with Sky 2" RSK and New V Code springs from ATS. Includes 5125 shocks and bilstien steering stabilizer, Sky track bar and bracket, and new Powerstop Rotors/calipers - EVERYTHING NEW UP FRONT.
*Since it's a 8x170 hub, I had an adapter to keep the Alcoas. I still need to do the rear axle to match the front SD D60 and wheel pattern. Then buy proper 8x170 wheels.

First drive, no more vibration. Woohoo! Yea, that lasted about a week.

Week later... vibration. At exactly the same speed, 60-70mph and didnt feel like the wheels, no steering wheel movement. Same cab vibration.

2 weeks later, I Put in a new Carrier bearing (whole assembly), all new U Joints in the rear drive shaft and 2" over stock rear blocks with 2.5* taper from PMF with new UBolts. Same Vibration. *I did mark the driveshaft to get it back together as it came off.

Few Weeks Later, Balanced and rotated alcoas... Same Vibration

Last week, I Bought a pair of new 16" 8x170 steels wheels for the front to remove the spacers, had the tires swapped over from the Alcoas to the 16" 8x170 wheels, balanced... Same vibration at 60-70mpg.

I put the camera under again and dont see the wheels and or suspension doing anything noticeable that hints a death wobble.



My next step: Going to remove the rear drive shaft and just drive it with the front and see if its always been the drive shaft being out of phase/balance. **Just went to go look at the rear axle and its not phased properly. I did mark it before I took it apart but didnt notice if it wasnt phased before... HMM.


Question: Can body bushings and or engine mounts be the cause of this vibration? Cab bushings dont look cracked and or hard. I can actually squeeze one. Been Planning to install the S&B Silicon Body mounts.

What Else should I consider inspecting? Is test driving it with the front Drive Shaft alone a bad idea?

Thanks in advance.

 

Mine was a bent rim .

 

i had a worn ujoint strap on the axle yoke causing my vibration

 

Wow, the timing of this thread is perfect.

01 F250, 7.3, Crew Cab, LB, 2wd

I took a trip from Dallas to Austin today. On the way back, I experienced the exact same vibration that Vasq1 described. It obviously wasn't coming from the front end. Steering wheel was not moving and no vibration from the front end. I've never felt a truck cab shake like that before. But it did feel like it was coming from the back of the truck.

After getting home, I found that my back left tire is badly worn on the outer edges, as if it had been driven under inflated. But the air pressure is fine. I also noticed that my LT Rear Tire is sitting 1 inch forward of the RT Rear Tire in the wheel opening. So, I'm starting to suspect a worn U Joint Strap like knottyrope found. But I don't see any movement or damage in that area.

I've run out of daylight, so I'll look closer tomorrow. Any other ideas?

 

So I got back under my truck this morning. The yoke on the drive shaft seems firm, and I found no looseness at either u-joint. Pretty sure I'm headed to the shop.

 

I have seen welded on balance weights come off in the past

 

You around the DFW area? What shop do you have to inspect this vibration?

I still need to phase my rear drive shaft. Not sure if when I assembled it I didnt phase it right, but I did mark it. Who knows. But tomorrow Im gonna drop the rear drive shaft to phase it properly and will just drive it with the front to see if it the drive shaft as a whole is the issue.

 

Ill check that or just replace it.

 

See if a local transmission shop is able to lift the truck and also strap it down so that it is possible to spin the driveline and visually (eyeball) inspect it.

Recently did this to find a vibration and it was traced to the transmission's tail.

 

It's definitely the driveshaft. I took it off, rotated the front piece 180* (since it only has two positions it will fit due to the wider spline) and reinstalled. Vibration was greatly reduced but still have a little. Think this is a result of the carrier bearing bracket bolts having a little bit of side to side play/adjustment. So not sure how to get the driveshaft perfectly aligned.

Gonna do the transmission shop suggestion. Found one that another OBS member suggested here in DFW.

But that's decent news. Still going to replace the cab mount bushings with the S&B kit.

 

mrbudtender2
1995 F150 5.0 2wd automatic
Hello all, I'm having same issue 😕 on a vibration can't pin down.
New rotors New pads New rear brakes drums shoes, New cyclenders, new front bearings, had an alignment done 3 weeks ago they said no issues 😳.
Now I've done everything to this truck since I'm 2nd owner crate 5.0 engine in 2008 150,000 trucks got maybe 200,000 .
Just installed new performance wires cap rotor coil egr and switch, sensors New, removed smog pump no catts, shorter strap 94 1/2 inch, but 30 to 45 mph vibration, then smooths out at 42 decelerate below 40 vibration begins below 30 mph smooth, then accelerate passed 30 vibration starts ends at 40 to 42 mph any ideas or point me please .

 

if you got a 2 piece drive shaft, and the truck is lifted in any way, the carrier bearing needs to be dropped to match that lift.

Or the carrier bearing is bad in genreal.

But there are lots of older threads on driveshaft phase, and driveshaft proper angles for the 2 piece drive shafts. But a majority of the issues came from bad carrier bearings or improper bearing height to the truck causing a bad driveshaft angle, blah balh.

 

Yup, have a 1" bracket to drop the carrier bearing to get the right DS angle. Carrier bearing and rubber "dampener" is new. The holes on the frame are what give about 1/4" lateral play in the carrier bearing bracket. Gonna check the angles at the rear yoke, DS and front yoke again.

I have some vid from under the truck after I turned the front piece of the shaft 180*. Definitely vibration looks like its coming from the front part of the Drive shaft and or xfer/trans side. Need to get more vid on that and check transmission mounts.

 

Driveshaft King in Dallas.

A few of us are in the area.

 

Sweet. Thanks.

*If y'all meet up somewhere to talk about OBS', let me know.