Caliper and Rotor ID.

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custodian

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I'm having a hard time cross referencing the rotor numbers and caliper numbers.

My truck is an 85 C10 that was originally a 6.2 with hydro-boost, the brake RPO code is J55 (heavy duty brakes), 5600 GVWR, 2WD.

The rotor casting number is either 3963996 or 3863886

I only looked at the right caliper and it's 18007153.

The calipers are big bore, I tried to measure the piston with a tape measure and it was around 2 15/16".

Any help cross referencing so I can buy the correct parts would be helpful.
 
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idahovette

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Could possibly be NAPA#CAL N4678 and CAL N4677 for the calipers and NAPA# 4885537 for the thicker rotors? NAPA #4885596 is the thinner rotors?
 

Keith Seymore

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The code you are interested in is JD3.

J55 is the "merchandised" option code for power brakes. Once the customer chooses that the engineering charts choose the specific system (the "unmerchandised" RPO) based on GVW and other considerations.

Yours is JD3 based on the 5600 lb GVW (thank you for that). "JB" codes are vacuum brakes, "JD" codes are hydroboost.

Your vehicle is represented by column 15 on the attached chart. This chart is what the engineers developed and used in order to release the specific part numbers for production and for service.

K
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MikeB

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RockAuto shows calipers are the same for JB5, JD3, and JD5.

CARDONE 184127 {#18005245, 18007947, 18015383} Remanufactured; Includes Installation Hardware
FitsFront Left; with Brake Code JB5; with Metal Piston
orFront Left; with Brake Code JD3; with Metal Piston
orFront Left; with Brake Code JD5; with Metal Piston

CARDONE 184126 {#18005246, 18007948, 18015384} Remanufactured; Includes Installation Hardware
FitsFront Right; with Brake Code JB5; with Metal Piston
orFront Right; with Brake Code JD3; with Metal Piston
orFront Right; with Brake Code JD5; with Metal Piston

I think that means that rotors are also the same for all three codes.
 

custodian

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Thanks for the info. A lot of different part numbers out there from different sources that's supposed to fit and work.
 

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