AC belt size?

[GM-power]

What's the right v-belt size for a all stock AC compressor? It has a 15545 on it now and that to small and a little long. What's the other size that will work? Its on a sbc.
Posted via Mobile Device

[raceman6135]

The 15 series belt (13/32" wide) should be the proper belt as GM used that on millions of small block and big block engines over a few decades.

Without knowing what year engine, what model of truck, what other accessories it has, etc it's difficult to tell what belt you need, but another common belt listed is a 15470 and also a 15480. Buy longer or shorter than those, depending on just how much "a little long" is.

[GM-power]

Its on the the truck in my sig with the rebuilt original engine,it has ps and alt. What was confusing when looking at the belts some say their for a brake booster, I thought those weren't belt driven. The 15545 on there is just to long. I've adjusted it as far as I can. It also rides down into the rides which makes it twist. Everything works but it chirps like crazy.
Posted via Mobile Device

[D13]

The diesels do not use 15 series standard belts, they are wider and industrial rated. Standard belts bottom in the pulleys. I'll have to search on one of the other boards to find out what I used. I was able to get mine at NAPA. Brake booster means when you have hydroboost (power steering ) assisted brakes. That is true on all 6.2's in squares. I don't remeber what belt I ended up with but mine has CuCV solid crank pulley which takes a little different length belt.

With props to my friends at dieselplace.com:

IIRC, the A/C belt was listed as 17/32" wide in the GM parts manual.

DAYCO and Delco Part # 15480, HC41, or #88934343 { Effective Length 48" / Outside Circ 48.57" / Top Width .44" / Angle 36 degrees. for Fan & Alt. This one is the proper width.

GATES Part # 7480 {High Capacity V-Belt (Standard) HC41 3/8" x 48 5/8"}
Fan & Alt., Optional Belt This one is too thin and will slip.

GATES Part # 5725 {Special Belt HC47 7/16" x 48 7/8"}
Fan & Alt., Preferred Belt. Proper width.

ACDELCO Part # 5725 {HC47 7/16" x 48 7/8" #88933926}
BELT,V FAN & ALT.; PREFERRED BELT; SPECIAL BELT This one is the correct width.