Were the rotors on it when purchased or did you do an OOPS?

 

They were on the truck when I bought it. I bought it from a dealer and one of the selling points was that they run truck thought the shop and check it over. It's about the third Captain obvious issue I have found with truck.

 

That's a safety issue right there and someone messed up with looking up the parts. GM is weird with parts combinations and why I don't mind the parts counter person asking for VIN and playing 20 questions.

 

4 wheel disc get smaller fronts

disc/drum get bigger rotors in front

Makes sense

 

After working at Auto Zone for a year I can not tell you the number of people that gave me attitude when I asked questions like "2 piston or 1 piston caliper?" All the companies mix and match parts. Just a fact that different trucks even though appearing to be the same may not be. One manufacturer gets a big blue F specifically because of buying parts in bulk and using them until they run out then just switching to what they have on hand. Many of their vehicles we had to ask build date. As mentioned above the rear drum vs disk brakes was one reason for a different size rotor. Even trucks with 4 corner rotors from certain years also have different size rear rotors. NBS trucks could come with 12.99" or 12.76" rear rotors and 12.01 front to both sets. This seems to be due to the trailer tow rating and intertwined with both engine size and gear ratio.

 

Here's some discrepancies I've noticed when I went digging around GM trucks and overhearing part counterperson parts requests:

99-02 and some 03 and 04's will have disk/disk brakes. Supposedly 03 was the disk/drum switchover when they did the redesign. SS Silverados were released in 2003 and will have front disk and dual piston rear calipers.
There are two different rear two piston caliper designs depending if it's 2WD or 4WD. They both use the same rotor.
If you have a Tahoe/Yukon you better know what drivetrain you have per the above discrepancy.
The rotors on the disk/drum trucks will have 11 holes, there's 3 for the set screw and two threaded holes to run a bolt through to help remove a stuck rotor.

 

thats false its the other way around its the front with bigger brakes and the rear with the smaller i know for a fact because I bought the wrong brake pads 3 times because i thought the same as you

 

Thanks for this tidbit, even if 8 years later... 🤷‍♂️ Everybody who posted in this thread haven't been on here in years.