Serpentine Belt Size Differential

[ursinaa]

I'm researching serpentine belts and found that belt sizes vary depending on the manufacturer of the interchangeable belts.
Yes, yes, I know. If I am so concerned, I can get the OEM belt and be done. But I like to learn all I can about a topic.

Not counting Continental's two belt option, the effective lengths run between 60" to 59.724" greater than 1/4" (0.276") difference.
In metric, 1531-1520mm, with ~the same 7mm or 0.27559" difference.
The top width has a much smaller differential at 0.033".

So, what is an acceptable size differential tolerance?
Some interchangeable belt makes for my car, a 2019 Subaru XV 6M 2.0L:

-Subaru OEM part 23780AA070​

I cannot locate the size online, and the print on my current belt has faded.​

​

-Goodyear Multi V-Belt 1060600 or 6PK1524​

Effective Length and Top Width (in): 60" by .82"
Effective Length and Top Width (mm): 1524mm by 20.8mm​

​

-DAYCO 5060597 or​

Effective Length and Top Width (in): 59.724" by .82"​

Effective Length and Top Width (mm): 1517mm by 20.8mm​

​

-GATES K060598​

Effective Length and Top Width (in): 59.83" by 0.807"​

Effective Length and Top Width (mm): 1520mm by 20mm​

​

-ACDelco 6K598​

Effective Length and Top Width (in): 59.84" by 0.807"​

Effective Length and Top Width (mm): 1520mm by 20mm​

​

-BANDO 6PK1525​

Effective Length and Top Width (in): 60" by 0.84"​

Effective Length and Top Width (mm): 1525mm by 21.336mm​

​

And the outlier award goes to Continental's two belt options:​

- MULTI-V 4060772​

Effective Length and Top Width (in): 77.20" by 0.83"​

Effective Length and Top Width (mm): 1964mm by 20.82mm​

- Metric Program 6PK1965​

Effective Length and Top Width (in): 77.36" by 0.81"​

Effective Length and Top Width (mm): 1965mm by 20.57mm​

 

[atikovi]

Go to the manufacturer's website for details. Most part numbers contain the belt's measurements.

ACDelco 6K598 = 6 ribs wide, K = shape of ribs or thickness, 598- 59.8 inches circumference.
Bando 6PK1525 = 6 ribs wide, PK = shape of ribs or thickness, 1525 mm circumference.

 

[IndianaDIY]

I think you're overthinking this.
I researched belts a while back and it seemed the Continental Multi-V was the best and most premium of everything.
Just go to Autozone, get a Multi-V, pull your old belt off, put the new one on and move on. The belt tensioner will make up a 0.0001 inch difference if there really is one at the end of the day.
I've put Continental Multi-V on Subarus/Toyotas/Rams/etc and they are pretty premo from the OEM.

Again, Go to Autozone, get a Belt, Take a picture of your old belt before removal, match the old vs new before you put it on to make sure they look similar in length....the old one will have stretched just a tad...then put the new one on.
You'll paralyze yourself otherwise over a 15min job.

Nice ride by the way. Subarus with Manual Transmissions are choice. My ideal would be an older Turbocharged Forester, manual, cloth seats and I'd drive it hard until it blew up.

 

[SHOZ]

I have an aftermarket one on now for the Gen Coupe. it fits really tight but fits. I ordered another one longer based on the speced length and it came it too short to put on..... Rock Auto closeout specials!!!!

 

[slacktide_bitog]

According to this image, it's a Mitsuboshi 6PK1517

 

[ursinaa]

According to this image, it's a Mitsuboshi 6PK1517

Sweet, thanks!

 

[Hall]

The belt tensioner can make up for all of the variations you list. The belt manufacturers know this and it's why they say those particular belts "fit". The Continental is clearly a mistake.