I'm having problems with replacement drive belts on my 2001 Chevy Malibu 3.1L V6..?

[John]

The belt seems to be aligned correctly and seated in the pulley grooves, but slips a couple of grooves toward the engine (back of the crank pulley) after a short amount of driving. I've replaced the tensioner and both idler pulleys, to no avail. so far, I've gone through 4(!) DAYCO belts. Should I try an OEM belt?

 

[Kenny D]

Check that the harmonic balancer crankshaft pulley is properly torqued. It may have slid forward if the retaining bolt securing it to the crankshaft was not properly torqued and has loosened, which occurs often after replacing the crankshaft position sensor which is behind the harmonic balancer. That engine has 2 crankshaft position sensors, one mounted to the side of the block and one behind the harmonic balancer crankshaft pulley and a misaligned serpentine belt can occur if the balancer is not installed properly after replacing the crankshaft position sensor behind it, causing the retaining bolt securing it to the crankshaft to loosen and the harmonic balancer crankshaft pulley to slide forward. The harmonic balancer crankshaft pulley looks like this:
http://info.rockauto.com/getimage/getimage.php?imagekey=515475&imageurl=http%3A//info.rockauto.com/RB/594-148-007.jpg

Proper installation requires the use of Loctite 771 or a similar thread-locking compound on the harmonic balancer retaining bolt and torquing it to 110 ft pounds.

 

[The-Razors-Edge]

Are you absolutely sure the pulleys are aligned properly? Perhaps you should check them out again.

 

[blanderswake]

I agree that you should recheck the alignment of your pulleys. As far as replacement belts, I would definitely stick with DAYCO.