Had the serp belt go on my wife's 1996 Seville STS. The knockout on the tensioner that a ratchet normally fits into to draw back the tensioner while routing the belt is an odd size. 3/8 drive is to small and 1/2 is to large. Do they make a special tool for this? Also the pulley that runs along side of the tensioner is "wobbley" which I'm assuming means the bearings are bad and it needs to be replaced. Any special name for this particular pulley. Got some buds at the Caddy dealership I can talk to tomorrow but thought I would post it here also. Got the car home so I can work on it in peace instead of in the gas station parking lot. Since the water pump is driven by it's own belt I was able to drive it without any overheating problems. Just REAL hard to turn. Thanks for any help.

Should be 1/2" AFAIK. Mine was tight. Gave the breaker bar a smack and in it went.

1/2 inch did work just needed a little "persuasion" to get it in. The pulley I was speaking of is the idler pulley. Is there a spacer behind it? The replacement did not have it. I cannot reuse the old one as it is shot. I'm thinking a dealer item. I'll find out tomorrow.