belt makers don't do that anymore. there is enough precision in belt making that any 2 of the same brand will be the same. there are many different belt qualities however and some may only last for a few years while others will last for tens of years. my truck does not use std length belts, so i cannot confirm size. original belt was 9470 and if you could get them in HD they would last forever
Parts guys will tell you that they don't make matched sets anymore, but that is not true, their just being lazy or don't know any better. If you call them on it, they just get POed, and probably won't help you out. If you are lucky enough to find a real parts guy, instead of some kid that can only find parts in the computer by make, model and year, you can still get matched sets with the little red tape around the set. Since real parts guys are as hard to find as hens teeth, have the kid bring out several belts and look for the production numbers on them. Belts are made in super wide bands and then cut into individual belts. There is a production number repeatedly printed across the entire width of the original belt. Different manufactures use different formats, but for instance Gates will use a format like 4914 163. There will be three or four of the numbers printed in a column across the belt with the last group progressing each time.
Like this:
4914 163
4914 164
4914 165
This is not the part number and is listed separately on the belt. The first group of numbers is the production number, the last group is that individual belts location in the original wide belt.
To get a matched set, get two belts that have the same production number. It is not uncommon to find belts that were next to each other, which is even better, such as:
4914 163
4914 164
4914 165
===========
4914 166
4914 167
4914 168
If your wondering how I know this, it's 25+ years experience has a professional heavy equipment mechanic. Heavy equipment uses a lot of matched sets. About 15 years ago the bs of no matched sets popped up with the excuse that production quality eliminated the need. Try running a 425 amp alternator on a fire truck without a matched set and you'll find out real quick what a crock that is.
