Topic: What's vibrating???

[Nimyad]

About a month ago I had my rear driveline flange come loose on the freeway and after i tightened it all was well again. But a couple days ago I started getting a bad vibration. It only happens if I'm holding a speed or accelerating, if I let off the gas and let it do compression it goes away, but if I just put in the clutch it's still there. It doesn't do it at lower speeds so I don't think it's my driveline. Rigs a 94 standard cab with a 22re, w56, dual 2.28s, and 5.29s. Lock right in the back. I'm thinking it's my pinion bearing or seal because it's slightly leaking but there's no pinion movement if I grab my driveline and try to move it. My tcase is also leaking a bit so I'm going to try to tighten down the flange more today.

[2manytoys]

Was it the rear diff flange?  If it was, you may be right about the pinion bearing. See if you have any metal in the rear diff.

[Nimyad [OP]]

It was the rear tcase flange.

[Rocksurfer]

When it came loose the 1st time the pinion will drop onto the carrier and grind against it, you may have damaged it and it has now damaged the ring gear too.

[Nimyad [OP]]

Well I took off the driveline and tightened the t case flange to probably 120lb and the vibe is gone now. But I have a crazy noise coming from the very edge of the pinion, almost sounds like it comes from where the seal is. It's not my locker because it does it only under absolutely no load and it doesn't sound like a locker popping. It almost sounds like something metallic tinging or pinging. I'm draining the fluid tomorrow and looking for shaving so we'll see.

[Rocksurfer]

The pinion may have dropped onto the carrier, when mine did that it acted exactly the same. Under power it lifted off the carrier and on coast it dropped back on to it. If it did you will clearly see the gear marks on the carrier.

[fordh8r]

if it's a very light metallic sound...is the dust shield bent on the flange? they can be easily dented and with some deflection under load it may rub the housing a bit.

[Nimyad [OP]]

I don't think the pinion dropped, the axle flange never got loose, there's no side to side or up and down movement at all in the pinion. Also it's a loud metallic sound, almost like there's something in the dust shield, it's a really hard noise to explain. I guess it sounds like a lunchbox locker popping, or pinging, but it has no effect of the vehicle, just sounds bad.

[fordh8r]

I had a similar noise not too long ago in my rig and it turned out to be the rear u-joint was starting to seize. Worth a look to see.

[Nimyad [OP]]

Thanks for the replies everybody. It's my rear u joint. Almost completely seized.

[fordh8r]

Don't ya just love an easy fix?

[Nimyad [OP]]

Very much so!