Little help please

[dmax_ty]

Have an 03 LB7 w/ 147XXX on the clock. It has started to squeak/squeal, but only when in gear, and driving.

Sounds like it is coming from the passenger side of the motor/dash and is more prevalent as you gain RPM's. Above 2k and it screeches like a banshee.

No loss of power, smoke, nada. Just an annoying squeak when driving.

Any help is greatly appreciated.

 

[catman3126]

do you have a EGR on this vehicle? sounds like the sound that comes from a exhaust leak before the turbo.

 

[catman3126]

if you have an egr cooler some LB7's had them the two bolt flang by the passenger side on the engine back by the turbo could be leaking of an uppipe either at the turbo or at the pass side manifold. look for some black soot at these joints and the ones behine the turbo with a mirror and light. those are hard to see.

 

[dmax_ty]

No EGR on this truck.

 

[The Neens]

leaking of an uppipe either at the turbo or at the pass side manifold. look for some black soot at these joints and the ones behine the turbo with a mirror and light. those are hard to see.

Ours was leaking at the turbo...12mm-12 point socket IIRC...

 

[Kspen90]

Have you checked the idler pulleys?

 

[dmax_ty]

Ours was leaking at the turbo...12mm-12 point socket IIRC...

10-4 will check it out.

Have you checked the idler pulleys?

First thing I did. Neither made any noise, and also replaced the tensioner just because I had one, but to no avail.

 

[catman3126]

sounds like an uppipe gasket then.

 

[Kspen90]

sounds like an uppipe gasket then.

For the OP's sake I hope not I'd just assume blow my own head off than unbolt the up pipes from the turbo again.

 

[catman3126]

For the OP's sake I hope not I'd just assume blow my own head off than unbolt the up pipes from the turbo again.

Really that bad Eh? I mean they are tight but yours must have really sucked. LOL

 

[Kspen90]

Really that bad Eh? I mean they are tight but yours must have really sucked. LOL

3 of the 6 broke they were so tight and one of the downpipe bolts broke too so yeah it definitely was no walk in the park.

 

[TheBac]

Have you checked the idler pulleys?

x2 Idler and tensioner pulleys. Nothing else.


PWI on my computer.

 

[dmax_ty]

x2 Idler and tensioner pulleys. Nothing else.


PWI on my computer.

Would they make noise if you just rev it up in park? It will only do under a "load" so to speak.

I couldn't get it to do it just free revving.

 

[Texas Chevy]

My vote is Some kind of exhaust leak. Is it a screech?

 

[dmax_ty]

Kind of a screech/squeal yes. I was leaning towards the idler/tensioner bearings as well being that it has 147k and still on the stock belt/bearings.

If it is an exhaust leak then lucky me lol. Those up-pipes sure are fun. :woott: