801

2006 E350 4matic, serpentine belt is chirping very loudly for about 10 minutes upon start up (especially first thing in the morning). Not a constant whine or squeal, but a rythmic, methodic and very loud chirp. As stated, goes away and quiets down after about 5-10 minutes. So which is it:

a. nothing

b. need new serpentine belt

c. need new tensioner

d. needs new serpentine belt AND tensioner

For the record, I've got about 79k on the odo. 2nd owner and to my knowledge (via carfax), this is the original belt but the tensioner has been replaced once. Any advice would be appreciated. thx.

Plutoe

My WAG is C

vettdvr

D + idler

baggee

Replace belt and alternator pulley.It has a non sliping clutch on it and it's gone bad - that's the couse of loud sound that you hear ...

801

Decided to err on the side of caution.
Replacing Belt, Idler pulley, Tensioner and AC pulley (to correct the jet engine whine). Alternator pulley checked out okay.