fatjet00

My belts started squeaking the other day. I remember reading on hear about the tensioner pulleys bearings needing re-packed with grease. Well I removed all the pulleys and sure enough they were all dry, both the serpentine ones, as well as the AC compressor pulleys. I re-packed them with wheel bearing grease. The noise quietened up a bit, but was still there. I go to Advance Auto parts to buy replacement belts. The belt they sold me was a Dayco 5060790. This belt was too long. The old belt # was 5060755. I bought this car used. Do you think someone installed an underdrive crank pulley.Thanks.

fatjet00

To those that have underdrive pulleys, Besides being smaller in outside diameter is there any other obvious differences between them and the stock pulleys? I know they sell a crank pulley what others do they sell that are underdriven? I even checked the crank pulley to see if there was an aftermarket name on it. I couldn't find one. This just baffles me that the stock part # serpentine belt was way longer than my old belt. I could literally put the belt over all the pulleys routed how it goes including the tensioner.

redls1bird

iTrader: (1)

The belt could have been boxed wrong. Its also a good reason to go to another store and cross reference with them.

Under drive pullies can be had for the power steering, alternator, possibly waterpump (cant specifically recall) and crank. It is not recommended to use an under drive crank pulley with any other pulley.

MrElectric03

iTrader: (71)

The stocker is cast and its pretty rough cast. Any aftermarket I have ever seen is smooth and looks much difference from stock.

fatjet00

The belt was not boxed wrong. My old belt I took off I could still read the #'s on it. The new belt I bought at Advance was a different #. I even looked up the #'s on Advances web site. Why is it not recommended to use an under drive crank pulley with any other pulley? For all you that are running under drive pulleys what is the last two numbers on the belt that fits properly? The belt that came off mine is 55' long. Thanks guys.

transambandit

iTrader: (6)

heres a big question, does your a/c work? if not i would bet your a/c compressor is going out, eventually the whole thing will freeze up and burn up your belt. You can either replace the compressor for about 300 bucks or you can get a replacement pulley from autozone for 40 bucks, a/c wont work. Thats what happened to mine, i thought it was the alternator bearing squealing but it wasnt.

redls1bird

iTrader: (1)

The a/c belt is separate from the rest of the pulleys on LSx motors. That would not cause the new belt to be too long even if it was included though.

You shouldnt use a UD crank pulley with any other UD pulley because the the crank pulley is designed to slow down the rotation of all the accessory drive components. If you slow down the rotation of lets say the alt pulley by the use of a UD crank, and then slow it down even more with the use of a UD alt pulley, it will no longer be able to charge the car at idle. Same goes for something like the water pump or power steering.

Check the length of your new and old belts compared to each other. Are you sure you had the routing correct?

fatjet00

Yeah I'm positive on the length of the belts. The one that is supposed to fit it is about 3" longer than the old one that came off. yes I'm also aware that the A.C has it's own seperate belt. That one was also longer as well. And my A.C blows ice cold. I took a tape measure and measured my crank pulley and got 5 3/4". Thanks guys. The things you come across when you buy a used performance car from a car dealer, and not an individual person. You have no clue as to whats been changed and what hasn't.