heres a question for you!

[mexicanjoe]

Ive got a little issue with LuLuBelle my '89 F-250 with a ZF5. IN the mornings when its cool and I take off to go to work I hear a rumbling/ somewhat whining sound emanating from the chassis . Ive checked the drive shaft, and its tight. The fluids in the tranny and diff and full( although I have added any limited slip additive since I changed the gear oil)
But here's the kicker: when it warms up, the sound generally goes away or its greatly diminished. [ years of competitive shootings will rob you of high pitch hearing.]So far the tranny shifts quite well, and I'm afraid it may be the throw-out starting to sing its swan song................Give me your opinions oh learned ones ! Your reader sits with bated breath

 

[Clb]

Only when moving?
Down low or high?
Front/rear?
Rpm/speed dependant?

Some thoughts...
Wheel bearings
Belt tensioner
Carrier bearing (driveline)
E brake gear for the rust belt guys


And then stupid long shot stuff like a loose centercap in a hub cap ( remember those?)
My v series square body has a shrill squeal emenation from the lower dash sometimes
( usualy when cold) not often so it freaks you out at first when ya hear it.....
These trucks keep power to the hvac fan motor when key is on, yup dry/worn bushes .

 

[mexicanjoe]

When moving forward, doesnt matter of rpms, clutch engaged or disengaged......

 

[DaveBen]

How about coasting?

 

[mexicanjoe]

coasting same thing......im thinking either throwout bearing, rear axle bearings or tranny fixing to give up the ghost. What bothers me it that it is not always constant, especially when the engine warms up or I travel a few miles. Pivot arm bushings???? May be the fan motor? Ill try and tear into the thing this weekend.

 

[Clb]

Envisioning humpty dumpty here

 

[Old Goat]

Check the Differential Yoke Nut.
Mine got loose, and I had this sort of rumble sound.
Dropped the DL and tightened it up. Rumble went away,
and also seemed like the clutch was grabby when starting
off. After it was tight, the Clutch became smooth.


Goat

 

[Selahdoor]

Joe I'm afraid you and I have the same problem. I've been trying to figure it out for years. And it is only getting worse.

I don't see how it can be anything in the front dif, or the axle shafts, if the front is manual, and unlocked, and the transfer case is out of gear.

But I have replaced ALL the axle and wheel bearings. The rotors, all brakes, drums, etc. Drained and filled both diffs. Checked all fluid levels. Checked for loose things like maybe the rubber inner fender shields maybe being loose and rubbing on a tire. I've checked everything I have been able to think of.

Fan motor. I dunno. I DO know that my fan is always blowing. It never stops or coasts. And it really doesn't seem to be coming from there.

It rumbles or roars, seemingly in time with the rolling of the truck. Doesn't seem like it speeds up or slows down with engine revolutions, only with the rolling of the truck.

The other day, though, while walking around the truck right after a cold start, I heard a rumble like you hear if a plane is high overhead. Only I quickly realized it seemed it was coming from the truck.

I replaced the belt tensioner less than a year and a half ago. That didn't make the rumbling stop. I have a new clutch for the AC, just haven't had the time to replace it yet.

Pretty sure it isn't the vacuum pump. Not sure about the power steering pump. If it was the water pump, I'd be losing water...

It just really sounds for all the world like the front bearings are metal on metal. Or even the front brakes. But like I said, I replaced all those!

 

[mexicanjoe]

Thanks for the info guys! Gonna try to get her back up to ***** this weekend if the creek dont rise and it gets above 55 degree......

.This morning I woke up and it was 90%+ humidity. Go the old gal started and warmed up before coming to work...... LuLuBelle ran like a veritable top!!! idled sooooo smoothly and no roaring noise!!
It appears she really likes cool humid mornings, so I let her have the reins!!!! I drove 2 miles into town while she was putting real estate behind her at a fast clip....