4X4 vibration @ 45mph and up

[rickpilgrim]

Our 87 F-250 X-cab lwb 4x4 w/460 C-6 has developed a wierd vibration at 45 mph and above when in 4x4 w/hubs locked.
Took a look underneath today and all u-joints are like new, front and rear driveshafts are nice and tight, everything in the TTB passed the test with no slop whatsoever. There is a bit of back & forth in the hubs(manual) and the only thing we saw was where the front axle goes into the spindle there is .107 of up/down/side/side movement.
What's strange is no vibration in 2wd, none when hubs locked and in 2wd drive at any speed up to 85mph! Only when your in 4x4/hubs locked does it do it. She has never been wrecked, off roaded or anything since day one. The tires are in balance and everything else checks fine.
Does anyone know if that .107 is possibly the cause? My dealer is no help with how much play should be here, they just said" there is no spec for this, bring it in and we'll look at it".

 

[Skandocious]

It's possible that you threw a weight on the front driveshaft. Do you see a spot near one of the ends of the driveshaft where it looks like a weight used to be welded on but is now missing?

 

[blacksnapon]

Lock in your hubs, then remove your front driveshaft and see if its still there. That'll eliminate or confirm a bad driveshaft.

 

[Skandocious]

Lock in your hubs, then remove your front driveshaft and see if its still there. That'll eliminate or confirm a bad driveshaft.

Good call. Could also be some kinda of strange vibration in the t-case so I'd also try running it in 4wd with the front driveshaft removed and the hubs UNLOCKED. That would test to see if the vibration is in the tcase.

 

[rickpilgrim]

Looked for wieghts also on both driveshafts and the both have one still there, sorry, forgot to mention that. What would do that in the T-case?

 

[Skandocious]

Nothing should do that in the t-case unless you've got something really messed up. I would be willing to bet that the problem is NOT in the tcase, but I figured it'd be good to rule it out.

Follow Vince's advice-- remove the front driveshaft and drive with the hubs locked. That'll isolate the problem to the front axle.

 

[1985 Ford F-150]

Probly just goin too fast in 4wd would be my guess.

 

[wizzard351]

ive run 80 mph with my 96 F250 with a 460 and never had a vibration.(yes i forgot to unlock it when we come outa the woods). id jack one front wheel up and set on jack stand and recheck u-joints with a small crowbar,sometimes they'll "look" good but even if they got a minor flat spot they vibrate. if you can try and spay some oil into the joints and see if that helps

 

[Terrell460]

Are your ball joints ok? my truck developed a vibration when the ball joints started goin to hell.

 

[Lost]

Like all said . U jionts can look and show little play and be shot. The Outer can go in under 100000 miles on a truck that see s little 4x4 use.

 

[conanski]

It's MUCH more common for the front axle U-joints to dry out from lack of use and poor maintenance so the fact they are tight doesn't tell you anything, they could be dry and that will create a bad vibration problem. The outer joints are easy to test for binding, park the truck with the wheels turned to something less than full lock, jack up a wheel, lock the hub and spin the tire, you'll see and feel if the joint is operating smoothly or if it's binding.

 

[rickpilgrim]

Today I pulled the front shaft,went for a ride- no change in 2wd or 4wd on the T-case. Then I jacked up the left front w/hubs locked, took a paint marker and put lines accrost the joints and we then put the old Hunter wheel balancer powerhead(1 hp electric motor w/drum to rotate wheel) to it and either forward or backward no play in the joints. Jacked up both fronts and spun it again, the Hunter only spins 25mph or so no big vibe but I can feel a tiny bit by the hubs.
As far as u-joints go, they were all new last yr while the 460 was out for the rebuild, and this is WI where 5 months a yr there is snow and ice. With a trailer 4x4 is a must and gets used alot.

What I did notice was 1- a good 1/8 turn slop in the front diff unit input side and 2-you can see with your eyes the right output shaft move up and down with power on/off applications with the Hunter. Time for a new Dana?

 

[wizzard351]

sounds like a good place to look! the shaft shouldnt move up or down. where are you at in wi? im up by the manawa area and i do have a spare front end from a desiel f250

 

[bvanmcknight]

Just wanted to say hi to everyone, and thank you for letting me in,

 

[Truckin4life]

make an intoduction thread here.... CLICK

 

[rickpilgrim]

sounds like a good place to look! the shaft shouldnt move up or down. where are you at in wi? im up by the manawa area and i do have a spare front end from a desiel f250


I'm up in Wausau, WI. You can PM me anytime. I may be interested in that in a few months when I can take the time to tear her down.

 

[wizzard351]

check your PM. your only about 45 min from me

 

[Big92F150]

Our 87 F-250 X-cab lwb 4x4 w/460 C-6 has developed a wierd vibration at 45 mph and above when in 4x4 w/hubs locked.
Took a look underneath today and all u-joints are like new, front and rear driveshafts are nice and tight, everything in the TTB passed the test with no slop whatsoever. There is a bit of back & forth in the hubs(manual) and the only thing we saw was where the front axle goes into the spindle there is .107 of up/down/side/side movement.
What's strange is no vibration in 2wd, none when hubs locked and in 2wd drive at any speed up to 85mph! Only when your in 4x4/hubs locked does it do it. She has never been wrecked, off roaded or anything since day one. The tires are in balance and everything else checks fine.
Does anyone know if that .107 is possibly the cause? My dealer is no help with how much play should be here, they just said" there is no spec for this, bring it in and we'll look at it".

i have the same thing but in 2wd.

im going to try some of the mentioned things to see if that works. i thought i was the only one with this problem

 

[A_G]

i have the same thing but in 2wd.

im going to try some of the mentioned things to see if that works. i thought i was the only one with this problem

check ujoints...i dont know if had been mentioned

But i grenaded my rear ujoint the other day (my own fault) but after i replaced it all my vibrations went away...it was a cadillac again...

 

[Fellro]

I just got a C6 out of Wausau... Be aware that both D44 and D50's were used int he diesel trucks depending on a few different factors. I have two diesels with D44's and two with D50's. The two D44 are regular cab 250's, the two D50's are an extended cab 250 and a straight wheel 350.