Hey fellas, need some help. Bought a set of "like new" calipers, rotors, lines etc etc from a fellow forum member whom has been helpful but when installing I ran into a problem.

The front caliper bolts are hitting the rotors, not all of them but a couple of them are. What does that mean, and what do I do?? My shop has suggested that I send these back to the seller and buy all new Calipers, not sure what to do have never had a problem on hear with anything I bought. The shop has tried everything from new bolts and just says these are worn and probably best not to use.

ADVICE!!! I paid really good money for them, so I expected a bolt on "like new" system.

Thanks for your help

Gerry

 

Hi Gerry

First of all - what bolts are you talking about???

Are you talking about the pad pin bolts (4 on each side of each front caliper, 3 on each side of the rear calipers) that screw in the side of the caliper and separate the padlets???

If that's what you're talking about, did the original owner put in some type of aftermarket bolts??? The OE bolts have either indentation for an Allen wrench bit or a Torx bit (early ones had the Allen wrench and starting in about 2008 they switched to the Torx). There are some aftermarket ones with a "bolt head" that you use a socket on.

You say "The front caliper bolts are hitting the rotors, not all of them but a couple of them are". Which ones are hitting - are the ones touching the rotor on the outside of the rotor, inside, or both sides???

Did you put on new aftermarket rotors along with the calipers???

What model car did you put them on - a Z06???

If not a Z06, are you using OE Z06 rotors???

I doubt it's a problem with the calipers at all.

If you're using an aftermarket rotor, it could well be that the offset is not precisely correct (a problem RB had with their rear rotors when they first came out).

So.....after we get some more info we can maybe come up some ideas!!

Bob

 

They are OEM calipers, but ARP racing bolts, does that sound correct??

Brakes are going on an 05 C6 Z51 with 3 piece forged wheels.

The rotors are not OEM they are Centric Rotors. My shop says its the calipers but I"m not sure.

 

Still not sure which bolts you are talking about. The caliper mounting bolts or the pad pin bolts. The calipers bolt directly to the knuckle using two bolts. The calipers will bolt to any C5/C6 knuckle. If one or both caliper mounting bolts are hitting the rotor on the inside the bolt/bolts are too long and can be replaced with GM bolts. Unless somebody milled down the caliper mounting ear a stock rotor should pretty much sit in the center of the caliper opening and stock pad pin bolts would not hit a stock rotor. If somebody stripped out some of the threads where the pad pin bolts mount in the caliper and repaired them by installing new thread inserts the pins may go further into the caliper and thus strike the rotor. This could be checked by inspecting the calipers to see if the thread inserts in various holes are at different depths.

Bill

 

Thanks you guys, it was the the non OEM bolts. Looks like the problem is Resolved.

Thanks again for your help.

 

As far as I know, ARP does not make the pad pin bolts for the calipers.

ARP does make lug studs. They are commonly installed to get a longer lug so that a spacer can be used with a wheel that may not have the correct backspacing/offset, and in racing applications open ended lug nuts are used so they will seat all the way down onto the wheel properly.

If you have longer ARP lug studs, are you using OE lug nuts? If you have extended lugs, the stock lug nuts may not be tightening down on the wheel all the way. It may seem like they're tight because the end of the lug is hitting the inside/end of the lug nut before the cone of the lug nut is seating into the cone-seat of the wheel.

Racing Brake makes some aftermarket pad pin bolts (the ones with the "bolt head"), but I have used them on my Z06 calipers with no problems at all. The RB bolt is on the right in the picture below:




However......take a look at this thread:

http://forums.corvetteforum.com/c6-z...-advisory.html


In the case of those Racing Brake rotors, I think RB just made the rotors with a wrong offset for our cars. Their solution to use a washer as a shim appears to work but seems kinda ghetto and should not be necessary with a correctly designed rotor.

I have not heard of any problems with Centric rotors, but I would suspect that they are the problem.

Were you having problems on the outboard side of the rotor, as in the case of the RB rear rotors???

If the problem is a very slight scraping on the outside of the rotor, are you sure the rotor is seated all the way against the hub???

If there is the slightest rust/corrosion on the hub, or if the rotor is just a little tight on the hub flange (they are hubcentric), and the rotor isn't perfectly flushly mated against the face of the hub, then you'll experience a problem similar to that RB rotor problem.

So.....I don't know exactly what the problem is, but I would bet it's not the calipers. I would suspect the rotors don't have the correct offset, or they aren't seating on the hub properly. If you have extended length lug studs, I'd also make sure your lug nuts aren't bottoming out before they seat properly on the wheel.

Bob

 

After hitting enter for my post above, I see that you say the problem is resolved.

However.....like Bill says - we're still not positive about what you're talking about.

What bolts were hitting the rotor???

This thread needs to be resolved as well, so that anybody having a similar problem in the future may have some info to work with!!!

What aftermarket bolts are you talking about???

Lug studs, pad pin bolts, or the 2 large caliper mounting bolts???

Bob

 

Using the RB bolts, and switched the rotors and was fine. They were the Pad Pin Bolts I was having problems with.

I still have the RB bolts and there is no problem now after switching to OEM rotors, not sure why the centrics had a problem.

 

Okay, so you switched back to OE rotors and pad pin bolts, and that solved the problem.

EXCELLENT!!

Still not sure what caused your problem.

I have used the RB pad pin bolts with no problem.

So.....I still suspect that the Centric rotors aren't the correct ones for the car, or Centric builds their rotors with a wrong offset.

Glad you got the situation solved!!

Bob

 

Thanks much