squeak squeak squeak!?!?!?!?!

[toddtheodd]

So.
Specs are.
72 custom 10 deluxe lwb.
350 engine, 350 trans, 2 piece drive shaft, 3.08 gears. Coil springs.
No a/c. :P

This just started yesterday, and it is not a "everytime" type thing.
My truck started squeaking on me under acceleration. It is at moderate acceleration only. WOT and DMD (DMD = Driving Miss Daisy) doesn't cause the squeak.
It does not squeak in neutral. Neither at the rpm nor at the mph. Only in gear. Which leads me to believe that this is not an engine thing. When I rolled down the window it sounded like it was coming from either directly under me to the rear of the truck. But we all know that sound locations can be deceiving at 40.
When I say that this does not happen everytime, I mean that I drove all the way to work today, and all the way to a resturant for lunch without any noise whatsoever. But while leaving I had to make a sharp left turn, and it started squeaking and continued to squeak (under moderate acceleration) for a little while, then eventually stopped again.

What the hell is this squeak. It is loud enough to be heard over my exhaust which sets off car alarms.

Also noticed that when I take a hard turn I would feel something go "thump" under the floor board. Could this be a related issue?

Any help would be great as this is my daily driver and I can't have it be down.

Todd

[WaitingImpatiently]

Sounds like a Drive Shaft U Joint to me, but then again, I'm an ammatuer at these things, just kinda figure em' out as I go.

[toddtheodd]

I can check the u-joints by trying to twist the driveshaft by hand yes? A little wiggle wiggle back and forth?

[kaycee]

Could be your center carrier bearing allso,and it could be your A-Arm bushings.

[toddtheodd]

A-Arm bushings? That would cause a squeak in gear under acceleration? Or could that be the thump under the floor boards?
I'm so confused.

[Super Duck]

Is it a 2 piece drive shaft?

[Longhorn Man]

I agree, it sounds like your U-joints to me. You can try shooting some grease in there, but if they are making noise, then it is probably too late to try and save them.

[toddtheodd]

2 piece yes. It has a carrier bearing.

[toddtheodd]

I must also point out that there is no vibration what so ever.
And this is also not an "all the time" or "everytime" squeak.

[Super Duck]

that would be my guess (caririor bearing) or just a gremlin

[WaitingImpatiently]

you can try twisting it, but on the other hand I had 1 worn out before and twisting on it I couldn't tell it was worn out. I would also try shooting some grease in them and see if it gets quiter???????

[WaitingImpatiently]

sorry, quieter...........

[toddtheodd]

Oh, and I don't know if this would matter or not, but it was kinda rainy the day before and it was also around 60 to 55 degrees last night when I first heard this.

[724wdcopper]

might check the bolts on the trans crossmember, too. had one side drop on me one time, not a pretty sound! could be a thump.

[toddtheodd]

Ok, so if it's the carrier... how do I fix that?
If it's the u-joints... how do I fix that?

[Super Duck]

Change them

[toddtheodd]

How would I be able to tell if it is the Carrier bearing over the u-joints? Any fancy stuff I can do to tell (like twisting the driveshaft)?
Todd

[Super Duck]

if you have never done it can be interesting. get a haynes manual for your truck and have fun

[toddtheodd]

Haynes is better than chilton I take it?

[Super Duck]

no just easer to get I personaly like chiltons better

[jlmtrout]

I used to hear that same noise just before my carrier bearing went out. Be sure you mark the drive shaft/yoke orientations before disassembly so that everything goes back together without having to re-balance the drive shaft. It's not hard, just time consuming and dirty. I used a large vice and a 3/4 in. socket to press the u-joints in and out. Good luck and keep on truckin'......Jerry

[68C15]

it sounds to me like a carrier brg. crawl under there & grab shaft ahead of it & try to wobble shaft. if it moves inside of U shaped cage then replace. remove complete shaft assy & try to turn joints by hand. if any roughness then replace. remove brg caps on rear joint & inspect. any rust or places where the rollers are dimpling the cross then replace. the carrier brg is hard to do without a press & some attachments so I suggest having the assy rebuilt by a driveshaft shop. much less down time & it is done right. (we have a cust who decided to do his own joints & ended up spending over $2000 in consequential repairs)
I am in no way implying that you are incapable, just saying because of the available timeframe it may be the best way.

[toddtheodd]

I figured out what it was and you'll never believe it.
...


Driver's side motor mount.

Which brings me to this...
I've never changed motor mounts before. What's the easiest way to do it? Any special tools I need, or will my regular socket set be enough.

Todd

[Brainchild]

Regular socket should be enough,but you will need to raise the engine to remove,and replace it.

One bolt comes through the bottom,and 3 hold the rubber pad to the block,and that's about it.Unless you have a bracket or something bolted in there.