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What Size are my Front Rotors?

A mid-size luxury crossover SUV, the Volvo XC90 made its debut in 2002 at the Detroit Motor Show. Recognized for its safety, practicality, and comfort, the XC90 is a popular vehicle around the world. The XC90 proved to be very popular, and very good for Volvo's sales numbers, since its introduction in model year 2003 (North America).
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ggleavitt
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What Size are my Front Rotors?

Post by ggleavitt »

What size front rotors does my Gen1 XC90 have?

Very common problem for XC90 owners is to determine the size of their front brake rotors.

Volvo built front rotors in 3 sizes for the XC90- 316mm, 328mm, and 336mm. A number of folks have tried over the years to get a solid "rule" about which vehicle gets which size as based on wheel size, engine, and MY. A few visual cues can help.

The 328mm front has double pot caliper, and the pad damper looks like this-
328mm caliper damper.jpg
328mm caliper damper.jpg (73.81 KiB) Viewed 677 times
If you have this damper on your front brakes, you have a 328mm rotor. That's it.

The 316 and 336mm fronts have a single pot caliper, and the pad damper looks like this-
316 336 mm caliper damper.jpg
316 336 mm caliper damper.jpg (86.35 KiB) Viewed 677 times
If you have this damper on your brakes, then it's a matter of determining the rotor size. See this photo for visual cues-
316 rear 336.jpg
316 rear 336.jpg (112.48 KiB) Viewed 677 times
316mm front on the left, 308mm rear in center and 336 mm front on the right.

316mm has no visual fins at the base of the center, 336mm has fins at the base of the center with approx. 1 inch between them. Photos are of OE rotors, aftermarket may be different.

Hope this helps.
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RickHaleParker  
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Post by RickHaleParker »

I would do something silly like measure them.
1998 C70, B5234T3, 16T, AW50-42, Bosch Motronic 4.4, Special Edition package.
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ggleavitt
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Post by ggleavitt »

You probably would. And I would pick up the phone and call Wayne Lyng over at Lisle and ask him so to each their own.

Many folks don't have the opportunity to easily measure, and it's a question that's been asked repeatedly since I joined this forum in 2006.

If someone sees something inaccurate in this post, please let me know, I'm happy to cover any other variances.
2006 V8 AWD Ocean Race-138k
2008 V8 AWD Sport-137k

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