Bad vibration in 4hi

[dentexpowerstroke]

Truck started having a bad vibration in 4hi when racing. Feels almost like wheel hop yet there isn't any. Only does it in 4x4 when I'm on it hard in high tunes, doesn't do it if I just cruise in 4hi also won't do it in 2wd at all. Anyone had this issue? I got under it this weekend and tried to see if anything was loose or rattling, came up with nothing. I'm figuring it's probably u joints that need replace but wanted some opinions.

 

[TrailerHauler]

Would you be able to narrow it down by, driving with just the hubs locked in 2wd, or hubs unlocked in 4x4, or does it need to have a load before it will vibrate? That could help point to axle shaft joins, or a drive shaft joint. The slip joint on my front drive shaft need to be replaced because its all blow out, gives me a nice vibration at high speed in 4x4.

 

[dentexpowerstroke]

Hubs stay locked all the time. It only does it in 4x4 on wot runs. It usually happens close to 40ish mph. I've tried to make it happen any other time and it doesn't, I tried all other variables.

 

[Arisley]

I would look at axle shafts. How long has it been since you tore your hubs apart and cleaned them out?

 

[dentexpowerstroke]

Never have. What would I be looking for with axle shafts

 

[Jarrod B]

why are your hubs locked all the time? you damage many parts doing that.

 

[Fordkid]

why are your hubs locked all the time? you damage many parts doing that.

Explain. Been doing for many years with no issues. 200,000k plus on one of the trucks. Unless your in 4x it just free spins

 

[Jarrod B]

Explain. Been doing for many years with no issues. 200,000k plus on one of the trucks. Unless your in 4x it just free spins

Ahhhh that might be the difference then. I was always told from others not to have locked hubs or locked transfercase on dry road due to the binding it does on the drivetrain up front. Ford even said not to be in 4wd on dry roads.

Now having the hubs locked and transfercase in 2wd idunno. In my case, my hubs are frozen on auto so they are not able to be turned. But still hold the vacuum and works with the switch.

 

[Fordkid]

It makes your turning radius worse.

 

[dentexpowerstroke]

I do it because whenever it rains even a little I get 0 traction.

 

[TrailerHauler]

Unlock your hubs and run it in 4x4, see if it still vibrates.

 

[Jarrod B]

I do it because whenever it rains even a little I get 0 traction.

go easier on the gogo pedal :slap:

 

[Arisley]

I have a rain tune. I call it "stock".

 

[Jarrod B]

I have a rain tune. I call it "stock".

in my case not so easy to flip to that setting lol.