Transfercase Vibration????? (1 Viewer)

[PF]

Still trying to chase down a vibration in my FJ62. It's like a whaaaawhaaaawhaaaa at 60 through 70 mph. Tonight I put the rear wheels up on jackstands, removed the tires and the brake drums, put it in drive and spun everything up to 65 mph. With the throttle lock engaged and everything spinning on I looked underneath (no I didn't crawl under it). The driveshaft looked smooth (plus I just had it serviced and balanced) so I used a broom stick to see if I could feel vibration in the casing of the other parts. After polking a few components the vibration seemed to be coming from the transfer case. I think the vibration was transferred through the rear motor mount and into the frame and body of the truck.

Is there anything in the TC that could go out of balance? Could it be the rear motor mount (probably never replaced)? Thing is driving me nuts.

 

[whitetaco95]

i would start by changing fluid in the rear end and transfer. Are your u-joints clocked the same way on the shaft? Basically so the ears line up.

 

[torfab]

also, make sure the front hubs are in free mode, and the front driveline spins freely

 

[Methusalem]

Hi, PF!
I had the same problem, but with another car. If you crawl under your car and try to move the drive shaft up and down, you feel play? Can be the drive shaft output bearing.

Wim

 

[alaska60]

check
fluid level...
U-joints...
flanges for play...



I'm rolling with a bad u joint on the rear shaft up at the TC.

 

[alaska60]

check
fluid level...
U-joints...
flanges for play...



I'm rolling with a bad u joint on the rear shaft up at the TC.

Im not personally rolling that way......
I think you may be though!!!

 

[elripster]

Often vibrations only show up when the powertrain is under load. However, even that can tell you something.

Since U-Joints are relatively cheap and easy to replace you might start there unless you know they are good. If that doesn't do it you might have a bad output flange bearing.

In my case I'm in the middle of chaning both. My output flange bearing looked all beat up and I could feel that the U-Joint was no longer pivoting through the range smoothly.

Frank

 

[PF]

Thanks, I have to rule out the driveshaft. I just had it overhauled and even had a CV installed to take care of the 30mph rumble.

I ran the whole drivetrain through the speed range with the tires off on jackstands and the vibration is definitely still there even without load. I'm leaning toward the last caller's suggestion of TC output bearing or spline. That would cover the fluid change, too.

Has anyone had sucess just changing the rear motor mount? That would be great, though I'm not holding out hope it's that simple.

 

[whitetaco95]

Is it lifted? is your pinion angle set perfectly to your driveshaft stlye?
Tom Wood's Custom Drive Shafts - Tom Woods Custom Drive Shafts Custom Driveshafts Specialist

 

[PF]

Yes, it's a 3" lift. My pinion angle is set to 1° down from straight at my TC. The -1° is to comp for axle wrap.

 

[wengejor]

I had a similar thing and I could get it to go away if I would release the clutch at speed and slowly engage it which would re-center it. I just got a new clutch, TO, pilot bearing and resurfaced the flywheel and had the trans & transfer rebuilt with new bearings and seals...

it seems to have gone away but I haven't done any long trips yet so we'll see.

 

[Kynot62]

Yes, it's a 3" lift. My pinion angle is set to 1° down from straight at my TC. The -1° is to comp for axle wrap.

I am not sure you can get axle wrap with a 62... On a serious note check the stake nut at the transfer case they do come loose on occasion. How many miles on the t-case? Is it full of 90wt or ATF? I have seen both, Atf tends to let things wear faster so things could be worn out. But even with 90 wt things wear.

If you have the original driveshaft I would put that back in and see if it still does it. CV joint seems a bit of overkill for a 3 in lift and one of the guys comments is still valid, make sure the slip yoke is in phase with the flange at the other end.

Tony

 

[PF]

I know what you mean about the axle wrap and I absolutely agree that the CV should be overkill for a 3in lift. But that's what it took to make the 30mph rumble go away. I tried all different axle shim setups and new u-joints before I finally gave up and had the CV put on.

Maybe that rumble loosened the outputflange or killed the output bearing. Or maybe it's the 230k miles.

I run 90wt. The CV is part of the old driveshaft so making that switch is kind of not an option.

Maybe it's time to learn how to rebuild the TC and cross my fingers that's where the vibs are coming from.

 

[PF]

Forgot to mention that the shaft is in phase.

 

[FJota]

What did you find in regards to your vibration. I have the same problem.