Brake Rotors Hairline Cracks..

[Destination Unknown]

Had a good luck at the rear Rotas and on the outside pad face there seems to be hair line Cracks right in centre line of where the pads run.

So is it a fit new pair ASAP.

[Dav L]

Probably due to overheat / too many heat cycles.

Time for new rotors and pads!

[TeJay]

You did not tell us where you were when you discovered the cracks. Dav L is correct inhis assessment. They need to be replaced.

I just want to let you know that it is not an immediate emergency. You have time so don't rush home or rush to get it done. Do your research as far as new rotors and pads.

This is a truck and you know that. There are differences in the quality of metal used in replacement rotors. Don't just search for the best price. The same is true for pads.


I don't know your background or repair expertise so if I insult your intelligence it was no my plan.

Go to several truck repair facilities and talk to the service manager and see if he can recommend a rotor or pad. What do they use?? If you find a semi truck repair facility that also services things like ambulances and delivery trucks based on the F-53 chassis. Those trucks are not making $$$$ if they are setting in a shop or if they require constant repairs because the shop does not fix it correctly. Those shops won't stay in business. Consequently they will use good parts that are of decent quality.

[Destination Unknown]

Originally Posted by TeJay

You did not tell us where you were when you discovered the cracks. Dav L is correct inhis assessment. They need to be replaced.

I just want to let you know that it is not an immediate emergency. You have time so don't rush home or rush to get it done. Do your research as far as new rotors and pads.

This is a truck and you know that. There are differences in the quality of metal used in replacement rotors. Don't just search for the best price. The same is true for pads.


I don't know your background or repair expertise so if I insult your intelligence it was no my plan.

Go to several truck repair facilities and talk to the service manager and see if he can recommend a rotor or pad. What do they use?? If you find a semi truck repair facility that also services things like ambulances and delivery trucks based on the F-53 chassis. Those trucks are not making $$$$ if they are setting in a shop or if they require constant repairs because the shop does not fix it correctly. Those shops won't stay in business. Consequently they will use good parts that are of decent quality.

Thanks you
We are in the UK so F53 American Service Garages are well not here. We would buy from Rockauto as they ship to UK and will go for OE speck on Rotas.
Just a shame that the Shipping is twice the price of the parts , then it's the dreaded import tax and vat to add at this end.

It's the rears which we will change first, which is the more evasive end to do and then set up.

[Philswrench]

Originally Posted by Destination

Thanks you

We are in the UK so F53 American Service Garages are well not here. We would buy from Rockauto as they ship to UK and will go for OE speck on Rotas.

Just a shame that the Shipping is twice the price of the parts , then it's the dreaded import tax and vat to add at this end.



It's the rears which we will change first, which is the more evasive end to do and then set up.

Have one of your local mechanics measure the thickness of your rotors,it has a minimum thickness as long as you stay .30 thousand above that you are ok, those little cracks are from heat they will machine out, depending on the rotor thickness, if you can give me the year of you coach I can give you the specs

[Dav L]

These are heavy rotors...no doubt the shipping would be the same as the price of the part to the UK.

I have always been surprised at the relatively modest cost these rotors are considering the weight.

You might want to add brake fluid flush to your service.

If you can't have the RV down due to parts not available locally, you might want to pull the wheels and see if the caliper pistons are not frozen. If they are, you want to add new calipers to your parts order.

To do so, take a screwdriver the try to push the pads apart (try not to damage the friction material with the screwdriver). If they loosen, then they are likely not frozen.

You might want to see if the bleeder screw can be opened in case that too is frozen.

You have to wonder why the rotors are cracking...overheat...frozen calipers....makes you think...

[Destination Unknown]

Originally Posted by Dav L

These are heavy rotors...no doubt the shipping would be the same as the price of the part to the UK.

I have always been surprised at the relatively modest cost these rotors are considering the weight.

You might want to add brake fluid flush to your service.

If you can't have the RV down due to parts not available locally, you might want to pull the wheels and see if the caliper pistons are not frozen. If they are, you want to add new calipers to your parts order.

To do so, take a screwdriver the try to push the pads apart (try not to damage the friction material with the screwdriver). If they loosen, then they are likely not frozen.

You might want to see if the bleeder screw can be opened in case that too is frozen.

You have to wonder why the rotors are cracking...overheat...frozen calipers....makes you think...

Calipers ect have been cleaned all round and new pads in rear, That is how I noticed the marks on the rotas.
Also had a full fluid change at same time.

[tderonne]

Have a picture? Some hairline cracks are normal. They are not very deep and do no harm.

[BarryG20]

As tederonne stated hairlines cracks are pretty normal just heat checking. They will turn out however I haven't turned a rotor in over 40 years. I run them until they get close to the min thickness then replace them. I have had a caliper freeze which in fairly short order trashed the pad and then started going into the rotor which required a replacement(well 2, if one rotor gets replaced I change both on that axle so they are the same and I do same with calipers) there was no turning that thing back into usable shape.

[Philswrench]

Minimum machine thickness is 28mm or 1".120 and lug nut torque is 140 ft.lbs.

[AITG]

Cracks on the face are not particularly serious. Cracks that extend out to the edge of the rotor should be out of service.

[Destination Unknown]

Hoping to get wheels balanced next week , so will try and get some pics of the discs (Roras)