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Mustang II Disc Brake Rotor, 5 on 4-3/4 Inch

Specs
Material Type:
Cast Iron
Weight:
14.60
Sold in Quantity:
Each
Finish:
Natural
Bolt Pattern:
5 on 4.75"
Stud Length:
0.93
Stud Diameter:
0.44
Thread Pitch:
7/16"-20
Flange Diameter:
5.74
Rotor Diameter:
9.25
MFG. Part #:
910-31002
Rotor Thickness:
0.884
Rotor Construction:
Vented
Garage Sale:
No
Rotor Location:
Front
Rotor Shape:
Round
Drilled:
No
Slotted:
No
Notes
Fits Mustang II/Pinto/Bobcat spindles. Replacement bearing cups for OEM: 912TLM12710 (cup, outer), 912TL68110 (cup, inner), Knurl dia. 0.475".
Mustang II Disc Brake Rotor, 5 on 4-3/4 Inch
Product Video
Mustang II Disc Brake Rotor, 5 on 4-3/4 Inch

Click image to enlarge

Watch the video below to learn how to correctly measure your wheel bolt pattern.

Details

Reviews

Q & A

What's in the Box

Vented stock 9-1/4" diameter brake rotors for 1974-1980 Mustang II, Pinto, or Bobcat spindles (or Speedway brake kits using '49-'54 Chevy spindles). Brake rotors are new, not plugged or re-drilled. Has a 5 on 4-3/4" bolt pattern with corresponding 7/16" diameter fine thread wheel studs.

  • Outside Diameter of rotor disc - 9.256"
  • Thickness of vented disc - .884"
  • I.D. of back side of rotor - 6.256"
  • Rear rotor face to bearing hub - .290"
  • Outer hub diameter where wheel will mount - 5.834"
  • Outer hub height - 1.450"
  • Bearing snout is 1.60" tall, 2.55" diameter at bottom and 2.384" at outer
    end.


Be sure to install new bearings and seals (910-31000) with your new disc brake rotors.

Customer Reviews

Rated 4.4 out of 5 by 10 reviewers.
RATING BREAKDOWN
10 reviews
5 Stars
7
4 Stars
2
3 Stars
0
2 Stars
0
1 Star
1
RECOMMEND THIS PRODUCT:

Denny1934
Chico, CA
Product Rating

Made them fit my 1973 Pinto

September 26, 2014
I took them to a brake shop and had them turned down to the minimum allowable thickness so they would fit my 1973 Pinto front suspension on my 1934 Chevy. They work great and I can now bolt on Ansen Sprint mags.
Yes, I recommend this product.
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mrchevy2u
Erie, PA, USA
Product Rating

great bang for your buck !!

September 21, 2013
this was a great way to keep in budget when wanting to upgrade my 34 ford kit car brakes to a 5 bolt chevy bolt pattern without the cost of a complete front suspension set up !
Yes, I recommend this product.
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circlehillb
Verified Purchaser
Tennessee
Product Rating

One &done

October 15, 2011
This was a good experience as always. Shipping was less than expected.
Yes, I recommend this product.
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Don
Verified Purchaser
Newberg, Oregon
Product Rating

Perfect Fit

June 15, 2011
Quick and easy like any job on your street rod should be! Got the rotor's, Bearing kits and dust covers and removed the old 4 luggers and had the new 5 luggers installed with in 2 hours of reciept of the goods from delivery. Wish all my upgrades went this way! Thanks Speedway
Yes, I recommend this product.
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1941 chevy
Staples,MN
Product Rating

Best product for the money!

January 23, 2010
The machine quality is not the best but for the price you can't beat them.
Yes, I recommend this product.
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krezkey
Painesville,Ohio
Product Rating

Perfect fit

August 30, 2010
Used to run GM 5 lug 4 3/4BC rims on my 1937 International D2 pickup with mustang II front suspension.Nice product for GM wheels to Ford Mustang II suspension without using wheel adapters.Great setup when used with the bearing and seal kit and new dust caps also sold here at Speedway
Pros:
  • Low Cost
  • Nice machine finish
Yes, I recommend this product.
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Uncle Buck
Scranton, PA
Product Rating

great products. are true and straight

July 05, 2010
great asset to my 30 coupe
Yes, I recommend this product.
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Rivi_the_racer
Verified Purchaser
San Ramon, CA
Product Rating

Small 9" GM rotors (mustang II)

January 20, 2012
these are low quality.. I decided to keep my US made rotors and was able to get them turned... While these rotors would have worked I really was disapointed in the quality
Pros:
  • Low Price
  • Would do the job
No, I would not recommend this product.
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Hot rod nut
Verified Purchaser
Burlington, Iowa
Product Rating

I would buy this product again and again

June 13, 2011
Great product
Yes, I recommend this product.
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dkr
Verified Purchaser
St. Louis, MO
Product Rating

Perfect Hard to Find Part

May 11, 2015
Ordered new rotors on Friday. Delivered around noon on Saturday. Good fit for stock mustang 2 drop spindles. GM wheel fit 4-3/4 bolt pattern good as well.
Pros:
  • very good price
  • Next Day Delivery
  • Great Oem Replacement
Cons:
  • None
Yes, I recommend this product.
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Page 1 of 1
91031002

Product Q&A

6 questions : 7 answers

1 answers

Would these fit on a 64 Mustang? Would these rotors and the calipers 91031045 be able to fit on the front of a 64 Mustang? Or is it very specific to a 1974 to 1980 Mustang? Changing from drums to disk.

neble
neble
October 09, 2013

Would these fit on a 64 Mustang? Would these rotors and the calipers 91031045 be able to fit on the front of a 64 Mustang? Or is it very specific to a 1974 to 1980 Mustang? Changing from drums to disk.

Answers

October 11, 2013
Jason
Brake rotor number 91031002 are for the Mustang II spindles and will not work on the standard Mustang. Speedway Motors does offer a complete disc brake conversion for the 64 to 66 Mustang under part number 91031971 which may be of interest.
2 answers

Races on new rotor Hello do these new rotors already have the bearing races installed? I am replacing my old mustang 2 rotors hopefully with your new setup and figured I'd replace bearings as well just wasn't sure if I needed the bearing kit with races or the 910-31000 kit thanks

Docerz
New Mexico, USA
July 07, 2013

Races on new rotor Hello do these new rotors already have the bearing races installed? I am replacing my old mustang 2 rotors hopefully with your new setup and figured I'd replace bearings as well just wasn't sure if I needed the bearing kit with races or the 910-31000 kit thanks

Answers

September 22, 2013
mrchevy2u
these rotors do not come with races in them . your new bearings should come with races manufactured for your particular bearings . I would never mix and match bearings and races do to manufactures using different tolerances during the making of products . going with a bearing/race kit is the way to go !
July 08, 2013
Jason
Yes, the races are installed on these new Mustang II rotors for the Mustang II/Pinto/Bobcat spindles.
1 answers

Can you tell me the stud size and thread size used on these hubs?

Wayno
Benton City, WA
January 06, 2011

Can you tell me the stud size and thread size used on these hubs?

Answers

January 10, 2011
Craig
These rotors part # 91031002 have 7/16" studs in them.
1 answers

What size are the rotors and can you get them crossdrilled and slotted?

Murphy
Maryville,Tn
September 14, 2011

What size are the rotors and can you get them crossdrilled and slotted?

Answers

September 14, 2011
Jason
This is a 9-1/4" rotor, sorry we do not offer this drilled or slotted
1 answers

do you get the pair or just one rotor when you order?

September 21, 2011

do you get the pair or just one rotor when you order?

Answers

September 22, 2011
Jason
These rotors are sold as each(1)
1 answers

Dust cap?? what is the correct p/n dust cap to use with these rotors?

Jnizzer
Plant City, FL, USA
April 11, 2015

Dust cap?? what is the correct p/n dust cap to use with these rotors?

Answers

April 13, 2015
EricM
Dust caps 91031071 or 91031072 fit this hub.
Page 1 of 1

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  • Outside Diameter of rotor disc - 9.256"
  • Thickness of vented disc - .884"
  • I.D. of back side of rotor - 6.256"
  • Rear rotor face to bearing hub - .290"
  • Outer hub diameter where wheel will mount - 5.834"
  • Outer hub height - 1.450"
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This bearing and seal kit includes two inner wheel bearings, two outer wheel bearings and two inner grease seals. This kit is enough for two brake rotors and is intended to be used with a new rotor installation as this kit does not include the bearing races or cups.

If your project willl be making use of used rotors, you will require new bearing races or cups.  Therefore you will need to purchase the bearing and seal kit # 910-31052 suggested below in place of kit # 910-31000.

Works with Mustang II/Pinto and Granada rotors using Mustang II/Pinto spindles only. It will not work for installing Mustang II/Pinto brake rotors on 1949-1954 Chevy spindles. Not for use with early Chevy spindle brake conversion kits.

-Large Bearing-
Thickness: .656"
Upper OD: 1.900"
Lower OD: 2.150"
Bearing ID: 1.375"

-Small Bearing-
Thickness: .651"
Upper OD: 1.380"
Lower OD: 1.570"
Bearing ID: 0.864"

Never install new hubs with old bearings.