FORD F450 VIBRATION ???

[79 HUSTLER]

I have a 2008 F450 4x4 with the 6.4 and low miles. I am having a vibration in the seat that starts once I hit 40-45 mph and I cannot diagnose. Below is what I have done so far:
-new rear driveshaft built and balanced up to 3,500 rpms (even removed and took back in to double check) .
-all new u-joints as well as new carrier bearing.
-rebalanced all tires (only 800ish miles since new) and one was a little off but still no help.
-ran a dial indicator on all four rear rims with zero movement.
-ran a dial indicator on the rear transfercase flange with zero movement.
-ran a dial indicator on the rear diff. flange with zero movement.
-placed the rear of truck on blocks with all four rear tires on and ran it up to 45-50 and vibration was still there.
-removed all four rear tires while blocked up and was able to run up to 80mph with zero vibration (points to the tires being the problem I would assume ).
-took the truck into another shop to balance tires (again) and they did not need to add a single weight as the tires are balanced.

What am I missing before I tear into this rear end ???

**UPDATE** I wanted to see if I could rule out the rims/tires so I used a pair that are definitely good and just ran one on each side. Hit the highway and the vibration started at 45 just as it had before. Might just end up being a long weekend effen with the rear end.

 

[HALLETT BOY]

Tires may be balanced but out of round , find a tire shop that can true them .

 

[79 HUSTLER]

Tires may be balanced but out of round , find a tire shop that can true them .

True, but they were smooth as shit up to 80mph before this little issue.

 

[oldschool]

Is it the Ford in your avatar?

 

[Lunatic Fringe]

Is it possible with that sudden load of going into low range, it twisted or slightly bent an axle shaft?

 

[79 HUSTLER]

Is it the Ford in your avatar?

No, that one vibrates from the moment it starts until it shuts down. But that one is do too the CAT Diesel. :tbi

 

[79 HUSTLER]

Is it possible with that sudden load of going into low range, it twisted or slightly bent an axle shaft?

Possibly, just hoping to find something else before ripping the rear end apart. But with no wheels on I would believe I would have some (although possibly less) vibration.

 

[oldschool]

No, that one vibrates from the moment it starts until it shuts down. But that one is due too the CAT Diesel. :tbi

Gotcha and I would imagine so. Sounds like something got tweaked when you had the transfercase issue.

 

[Lunatic Fringe]

I have the same truck.
Was yours shift on the fly? I assume it had to be.

 

[glamis0812]

Wow I had that same thing happen to me on a 2008 F250 while I was towing. I guess I got lucky on mine it only blew apart the front diff and destroyed the front shaft. Mine always had a weird noise in the driveline I could never figure out. I ended up selling it with only 15k miles.

 

[79 HUSTLER]

Wow I had that same thing happen to me on a 2008 F350 while I was towing. I guess I got lucky on mine it only blew apart the front diff and destroyed the front shaft. Mine always had a weird noise in the driveline I could never figure out. I ended up selling it with only 15k miles.

Just a little Internet searching and its a lot more common then I ever would imagine. Sounds like you got lucky. This was just a portion of my aftermath.
View attachment 513290 View attachment 513291 View attachment 513292

 

[Hullbilly]

(If you have not already)
Try having a dynamic balance done, where they match the rim run out to the tire runout. Just because they "balance out" doesnt always mean they will be smooth.

Other possibility could be a slipped or busted belt in one of those tires, no guessing what all took a good hit when the tcase decided to lock up.

 

[Hullbilly]

Just a little Internet searching and its a lot more common then I ever would imagine. Sounds like you got lucky. This was just a portion of my aftermath.
View attachment 513289 View attachment 513290 View attachment 513291 View attachment 513292

Some serious carnage!

 

[glamis0812]

It was a cool truck but it had to go plus I'm a Chevy guy

 

[Angler]

Did you have the main drive shafts balanced? If not, I would start there.

 

[JDKRXW]

Did you replace the flex-plate when the trans was out?

 

[Flying_Lavey]

F-450 so it's not dually, we're the inner and outer wheels indexed correctly to each other when installed? Typically just having the valve stems opposite each other is correct but not always. And usually well balanced wheel/tire assemblies aren't sensitive to this but it's possible. If not, I'd check the axles. Without the wheels & tires there could be not enough mass to cause the axles to actually vibrate

 

[Havaduner]

Tires may be balanced but out of round , find a tire shop that can true them .

True, but they were smooth as shit up to 80mph before this little issue.

I'll second finding a tire shop that can true the tires.... I had one on my Kodiak go bad after they'd been on the truck for about a 1000 miles. It wouldn't vibrate till about 60-65, over 65 it would go away. It would be a quick and pretty cheap thing to check before you started tearing the truck down again....

 

[2FORCEFULL]

So to preface this, FUCK THIS FORD, but I need to get this fixed. I have a 2008 F450 4x4 with the 6.4 and very, very low miles. 4th of July we were coming home across the desert towing about 15k pounds and the transfercase decided it wanted to go into 4 low at 70mph. Grenaded the transfercase, transmission, front driveshaft, rear driveshaft, wiped out the fuel lines, fuel pump, and wiring harness. So I have everything back together (minus front drive shaft) but I am having a vibration in the seat that starts once I hit 40-45 mph and I cannot diagnose. Below is what I have done so far:
-new rear driveshaft built and balanced up to 3,500 rpms (even removed and took back in to double check) .
-all new u-joints as well as new carrier bearing.
-rebalanced all tires (only 800ish miles since new) and one was a little off but still no help.
-ran a dial indicator on all four rear rims with zero movement.
-ran a dial indicator on the rear transfercase flange with zero movement.
-ran a dial indicator on the rear diff. flange with zero movement.
-placed the rear of truck on blocks with all four rear tires on and ran it up to 45-50 and vibration was still there.
-removed all four rear tires while blocked up and was able to run up to 80mph with zero vibration (points to the tires being the problem I would assume ).
-took the truck into another shop to balance tires (again) and they did not need to add a single weight as the tires are balanced.

What am I missing before I tear into this rear end ???

what I have seen happen is the paint on the hub centric keeps the inner wheel from going on straight... them they torgue the wheel and it cut a crooked groove

are they 10 lug?

 

[OCMerrill]

Can the rear driveshafts be installed out of phase? Don't know if that's possible on a F450.

 

[79 HUSTLER]

Did you replace the flex-plate when the trans was out?

No, still the original.

 

[79 HUSTLER]

Can the rear driveshafts be installed out of phase? Don't know if that's possible on a F450.

It is a 2 piece shaft but it was balanced with both pieces together and the boot installed. Was removed and double checked if balanced up to 3,500 rpm's then put back in.

 

[79 HUSTLER]

what I have seen happen is the paint on the hub centric keeps the inner wheel from going on straight... them they torgue the wheel and it cut a crooked groove

are they 10 lug?

Yes, 10 lug and they are seating completely on the hub.

 

[79 HUSTLER]

**UPDATE** I wanted to see if I could rule out the rims/tires so I used a pair that are definitely good and just ran one on each side. Hit the highway and the vibration started at 45 just as it had before. Might just end up being a long weekend effen with the rear end.

 

[2FORCEFULL]

**UPDATE** I wanted to see if I could rule out the rims/tires so I used a pair that are definitely good and just ran one on each side. Hit the highway and the vibration started at 45 just as it had before. Might just end up being a long weekend effen with the rear end.

I have a set of 10 lug 22.5's that fit that truck with no adapters...tires and wheels:thumbsup

could the drive shaft be out of phase???

 

[2FORCEFULL]

i'm betting on drive shaft issue... missing shims on the trans mount... bad carrier bearing or shims missing... out of phase drive shaft joints..


put a go pro under there..

 

[79 HUSTLER]

i'm betting on drive shaft issue... missing shims on the trans mount... bad carrier bearing or shims missing... out of phase drive shaft joints..


put a go pro under there..

No shims missing, new carrier bearing came with drive shaft, drive shafts are phased. Driveshaft is not moving when its at 45mph.

 

[jb600]

How about the cross member that carrier bearing bolts up to for the rear drive shaft. Did that get bent? Possibly changing the angle of the drive shaft?

 

[OCMerrill]

i'm betting on drive shaft issue... missing shims on the trans mount... bad carrier bearing or shims missing... out of phase drive shaft joints..


put a go pro under there..

I have a set of 10 lug 22.5's that fit that truck with no adapters...tires and wheels:thumbsup

could the drive shaft be out of phase???

Next time I see you we will discuss my copyright on post 20.

 

[OCMerrill]

Take the prop shaft out. Start the truck and put it in D and run it up to 45-50 mph. See what that tells you.

You can also get real carried away and go top the top of a hill, remove the shaft, and coast down and see what you get.

I did that very thing with my motor-home because Ford said the vibration was in my head. Turns out the shaft was way out of balance. I had a driveline shop fix all that BS.

Ford is basically a fuckfest of issues they are no help with.

 

[pronstar]

How about the cross member that carrier bearing bolts up to for the rear drive shaft. Did that get bent? Possibly changing the angle of the drive shaft?

I had a similar dealio happen on my Dodge.
Was an ass-kicker trying to figure it out.

Also, have we eliminated death-wobble, even if a slight case, from the equation?
If the steering wheel isn't shaking, you're probably OK.

I had "death wobble without steering wheel shake" once, turns out I had blown the seals out of one of the the early Carli Commuter Kings I was evaluating.
The front wheel was oscilating, undamped.

 

[79 HUSTLER]

Take the prop shaft out. Start the truck and put it in D and run it up to 45-50 mph. See what that tells you.

You can also get real carried away and go top the top of a hill, remove the shaft, and coast down and see what you get.

Ran it up to 80mph without driveshaft and zero vibration. If I have to take it to the top of a hill the only thing I will be doing there is forgetting to put it in park and cracking open a beer while watching the ghost ride...

 

[79 HUSTLER]

I had a similar dealio happen on my Dodge.
Was an ass-kicker trying to figure it out.

Also, have we eliminated death-wobble, even if a slight case, from the equation?
If the steering wheel isn't shaking, you're probably OK.

I had "death wobble without steering wheel shake" once, turns out I had blown the seals out of one of the the early Carli Commuter Kings I was evaluating.
The front wheel was oscilating, undamped.

Zero vibration in the steering wheel. Just from the seat.

 

[79 HUSTLER]

How about the cross member that carrier bearing bolts up to for the rear drive shaft. Did that get bent? Possibly changing the angle of the drive shaft?

Going to head out and take a look at that now.

 

[28Eliminator]

Drive shaft is out of time (phase). Crosses (u joints) need to line up perfectly with each other, if not it will get a harmonic vibration at different speeds. I went through this years ago. Had the flange cut on one end of the driveshaft and lined up correctly and the vibration went away.

 

[79 HUSTLER]

Drive shaft is out of time (phase). Crosses (u joints) need to line up perfectly with each other, if not it will get a harmonic vibration at different speeds. I went through this years ago. Had the flange cut on one end of the driveshaft and lined up correctly and the vibration went away.

Drive shaft is phased. All three crosses are in lined up.

 

[2FORCEFULL]

I would just go to who ever did the drive shaft...

 

[28Eliminator]

Drive shaft is phased. All three crosses are in lined up.

Perfectly?

 

[pronstar]

Zero vibration in the steering wheel. Just from the seat.

Shocks are good, too?

 

[79 HUSTLER]

I would just go to who ever did the drive shaft...

Drive shaft was built by ccidriveline ( http://www.ccidriveline.com/ ) in Michigan. They were contacted about the drive shaft after it was installed and I asked what rpm they run the machine up to and they stated 3,500 rpm. Since I still had vibration after installing I took it to a local shop to check for balance and they ran their machine up to 3500rpm's as well and did not have to do a thing to the shaft. At 45mph in the truck the rpms are around 1500 while driving.

 

[79 HUSTLER]

Perfectly?

While I have not personally ran it across my lathe, I would assume so. As was stated earlier in the thread the second shop also ran it up to 3500 rpms on their machine and if they were out of phase, the problems would have shown at that time. I would assume.

 

[79 HUSTLER]

Shocks are good, too?

Same shocks as before the little incident. Cannot see any visual damage to them but I do not believe the shocks play any part in this.

 

[Cray Paper]

Why only 3500 RPM on the driveshaft? Maybe I'm not thinking clearly here but engine RPM has little to do with drive shaft rpm when considering vibrations. There's a transmission with 6 - 8 different gear ratios, fixed differential gear ratio and tire size that matter more than engine RPM. An out of balance drive shaft will be felt much more as speeds advance. All that vibration gets compounded by the stuff down stream as speeds increase.

 

[79 HUSTLER]

Why only 3500 RPM on the driveshaft? Maybe I'm not thinking clearly here but engine RPM has little to do with drive shaft rpm when considering vibrations. There's a transmission with 6 - 8 different gear ratios, fixed differential gear ratio and tire size that matter more than engine RPM. An out of balance drive shaft will be felt much more as speeds advance. All that vibration gets compounded by the stuff down stream as speeds increase.

Correct. But that is what both companies spin them to. I would assume just like balancing a tire they do not spin very high rpms when balancing but they are fine when spinning much higher rpms on a vehicle. Both stated balancing the shaft at 3500 was plenty for a diesel.

 

[Flying_Lavey]

Both stated balancing the shaft at 3500 was plenty for a diesel.

What does the diesel have anything to do with it? A diesel truck goes the same speed as a gas truck and the drive shaft speed is ground speed dependant. There is no 2 speed axle in a F-450 so the diesel aspect has no bearing on the shaft speed

 

[79 HUSTLER]

What does the diesel have anything to do with it? A diesel truck goes the same speed as a gas truck and the drive shaft speed is ground speed dependant. There is no 2 speed axle in a F-450 so the diesel aspect has no bearing on the shaft speed

I never said it did, just stating what they stated to me. When I'm trying to figure something out I try to list as much info as possible. CCI builds drive shafts for race cars which spin some serious rpm so they stated that balancing on their machine to 3500 rpms was plenty for a "diesel". The second shop also made the same statement.

 

[Flying_Lavey]

I never said it did, just stating what they stated to me. When I'm trying to figure something out I try to list as much info as possible. CCI builds drive shafts for race cars which spin some serious rpm so they stated that balancing on their machine to 3500 rpms was plenty for a "diesel". The second shop also made the same statement.

Yeah, I understand that's what they said. That's why I brought it up. The fact that they would state that is odd. Do they balance their race car shafts to a higher RPM.

 

[Your ad here]

Are the front hubs unlocked? If you have the dash switch 4x4 the hubs should be on auto to be unlocked. If you have 4x4 on the floor the hub should be on free to be unlocked.

 

[79 HUSTLER]

Are the front hubs unlocked? If you have the dash switch 4x4 the hubs should be on auto to be unlocked. If you have 4x4 on the floor the hub should be on free to be unlocked.

Yes front hubs unlocked as well as no front drive shaft yet. It's a electric knob for 4x and manual locking hubs.

 

[Angler]

I take it the front tires locked up for a few seconds when it went into 4 low? There could possibly be a very small flat spot on the tires causing the vibration, happened to a friends truck.