Aftermarket Spindles and Rotors

[Cody the Roady]

I have a 1987 Chevy Silverado R10, 2WD. My mechanic gave me a set of drop spindles for free. I took off the old spindles and put on the new ones. However, after replacing the wheel bearings, the rotors do not fit all the way on. I have been researching the meaning of "1 inch or 1 1/4 inch" here and other places...and I'm still confused. I do not know the brand of the new spindles. My son "the expert" says I am replacing 1" spindles with 1 1/4" spindles. Does this mean I need 1 1/4" rotors? Does this also mean I will need new calipers? Thanks, guys.

[jetmech]

The reference to 1" vs 1 1/4" is the rotor thickness. The spindle, rotor and caliper have to be matched for one or the other. If you are removing spindles made for 1" rotors and replacing with 1 1/4" spindles then you will also need 1 1/4" rotors and calipers. When I do this conversion I also change to a dual diaphram brake booster and Suburban rear brakes and backing plates. This makes an excellent braking system for a half ton truck.

[Cody the Roady]

Makes sense. Thanks for the response.

[Captkaos]

I thought I put a post in the tech section on the HD vs std brakes, but I don't see it...
I will try and get it posted, but as stated, if your spindles are for HD (1-1/4") brakes, you will need to change out your rotors/calipers

[Cody the Roady]

Looking closer at the spindle I have with me right now, it is stamped "C-10D" (I assume D is Driver's side), and "C10-HD", which I bet is, per Capt. Kaos, short for heavy duty. Now we're cookin' with gas! Again, I appreciate all y'all's help.

[Captkaos]

Posted the pic comparison...
http://forum.73-87chevytrucks.com/smforum/index.php?topic=30569

[Cody the Roady]

Thanks, Capt! Now, if I can only get my local parts store to understand this. I've shown them the new spindle. I've printed out y'all's explanation. I have just printed your pictures for a graphic display. I'm confident that, though I am mechanically deficient, explaining it correctly. Any advise on what I need to "say" to my parts guy? He seems to be under the impression that the HD spindle will require a different bolt pattern.

[Captkaos]

Tell them you need rotors for JB5 brakes

JB3 = power brakes, 1" rotors
JB5 = power brakes, 1.25" rotors

[Cody the Roady]

We have a success story! I finally got through to a local parts guy. Before him, everyone kept looking stuff up on their computer. Then came Steve, the manager at the local O'Reilly's. He pulled rotors and calipers out from the back and played with my spindles for an hour. They're on the truck now. Again, I thank you gentlemen for all the pics and answers. Now, on to the rear....