[Glenn44]

I have one bolt but was missing one. So I ordered one off eBay and it is smaller than the one I already have. Did they send me the wrong one or is one supposed to be smaller than the other?

The caliper is 40 miles away so I can't just go take off one of the other calipers and check. A quick answer would be greatly appreciated.

 

[spiderserie4]

if you mean the 2 ATE caliper mounting bolts on the one caliper, then yes, same

my S4 parts book gives two PNs, one for fronts and another for rears

or did you mean the special bolts that hold the caliper halves together?
like these?


OH, I see this was just answered very precisely


Edit: If I am not mistaken the fronts have a shoulder

 

[bobcor]

I have one bolt but was missing one. So I ordered one off eBay and it is smaller than the one I already have. Did they send me the wrong one or is one supposed to be smaller than the other?

The caliper is 40 miles away so I can't just go take off one of the other calipers and check. A quick answer would be greatly appreciated.

The front caliper bolts are 12mm x 1.5 x 34mm . The rears ar smaller 10mm x 1.25 x 28mm

 

[bobcor]

The front caliper bolts are 12mm x 1.5 x 34mm . The rears ar smaller 10mm x 1.25 x 28mm

if you mean the 2 ATE caliper mounting bolts on the one caliper, then yes, same

my S4 parts book gives two PNs, one for fronts and another for rears

or did you mean the special bolts that hold the caliper halves together?
like these?
View attachment 1668993

OH, I see this was just answered very precisely


Edit: If I am not mistaken the fronts have a shoulder

Yes you are correct

 

[Glenn44]

I am referring to the two bolts that mount the caliper on the disk. I had them rebuilt, now to mount them I attach the brake line and then use the two bolts to attach them to the car.

 

[bobcor]

I am referring to the two bolts that mount the caliper on the disk. I had them rebuilt, now to mount them I attach the brake line and then use the two bolts to attach them to the car.

The bolts referenced above are the ones that mount the caliper on the car ( the steering knuckle to be precise ) The disk and wheel hub are mounted as a unit on the steering knuckle so that when the caliper is mounted to the knuckle the disk spins between the caliper.

 

[Glenn44]

Right. So both bolts the same size? Or different sizes for the front and rear ones?

 

[bobcor]

Right. So both bolts the same size? Or different sizes for the front and rear ones?

Re-read post #3. Different sizes for front and rear. Both bolts for front are the same and both bolts for the rear are the same. The size difference relates to the front vs. the rear.

 

[Alfajay]

I have one bolt but was missing one. So I ordered one off eBay and it is smaller than the one I already have. Did they send me the wrong one or is one supposed to be smaller than the other?

Before anyone can give you a reasonable answer, you'll have to tell us what you mean by "size". Is the ebay bolt:

• Shorter?
• Smaller in diameter?
• Length and shank diameter are OK, but the head size is smaller?

 

[spiderserie4]

I am referring to the two bolts that mount the caliper on the disk. I had them rebuilt, now to mount them I attach the brake line and then use the two bolts to attach them to the car.

I have one bolt but was missing one.

yes, but which caliper is missing a bolt, the front or the rear caliper...........?

So I ordered one off eBay and it is smaller than the one I already have. Did they send me the wrong one ........

more likely you ordered the wrong one, because you did not know they were a different size for front and rear caliper

 

[Glenn44]

Got it all cleared up. eBay didn’t specify as the selle didn’t know front and rears were differentent sizes. He’s sending another. Thanks to all.