rear brakes hotter than the fronts

[kenjisak]

hey guys, i have a 2011 a4 quattro. i was just curious to see if everyone elses quattros have the rear brakes hotter than the fronts. after a 5 min drive my fronts are still cold while my rears are scorching hot where i cant leave my fingers on the rotors even for half a second. been to a couple shops and theyve all couldnt find an issue but i do remember going on a trip awhile back using the highway and the rears were cold.so curious to know if this is a normal thing.

Sent from my SM-N950W using Audizine Forum mobile app

[A4x]

I've never gone poking at hot brake calipers before (actually I did one time, and I won't do it again).

I do know that the fronts use a vented rotor, while the rears use a solid rotor. So the fronts are much better at cooling down.

The fronts are also a lot larger which will help with cooling.

[morris39]

hey guys, i have a 2011 a4 quattro. i was just curious to see if everyone elses quattros have the rear brakes hotter than the fronts. after a 5 min drive my fronts are still cold while my rears are scorching hot where i cant leave my fingers on the rotors even for half a second. been to a couple shops and theyve all couldnt find an issue but i do remember going on a trip awhile back using the highway and the rears were cold.so curious to know if this is a normal thing.

Sent from my SM-N950W using Audizine Forum mobile app

If you are using ACC routinely in traffic the rear brakes are the ones used to control separation distance. That minimizes pitching but is usually fairly mild so there could be other reasons.

[kenjisak]

If you are using ACC routinely in traffic the rear brakes are the ones used to control separation distance. That minimizes pitching but is usually fairly mild so there could be other reasons.

there could be but after going to 3 shops and tried diag and replacing parts myself im just hoping this is a normal thing. im getting 550km for a full tank which is almost all highway. dk if thats reasonable mileage for the winter. already replaced the master,rear left caliper, changed all slide pin boots so they move freely and rebled brakes about 3 times. dk what would cause the dragging if this isnt a normal thing

Sent from my SM-N950W using Audizine Forum mobile app

[Traptalk]

I’ve noticed with my bbk set up (q5/macan front / s4 rear / ecs wave 2 piece drilled & slotted rotors) that only my rear rotors have cracks...

[A4B8 2.0tfsi]

......im getting 550km for a full tank which is almost all highway. dk if thats reasonable mileage for the winter.[/URL]

That is not especially good milage numbers. If rears are seizing up due to old break fluid or other, than I would understand your numbers, but all highway, you should get in the 700's

[kenjisak]

That is not especially good milage numbers. If rears are seizing up due to old break fluid or other, than I would understand your numbers, but all highway, you should get in the 700's

new brakes,new fluids, new slide pin boots,carriers wire brushed and serviced, replaced master and rl caliper. no abs codes show up. anything that you might think could be the cause? ive been to reputable shops and they all think its fine cus the wheel moves and turns but i just think theres an ever so slightly bit of constant contact thats making it so hot. i did 3 kms of driving last night and the rears were untouchable vs fronts were ice cold

Sent from my SM-N950W using Audizine Forum mobile app

[Theiceman]

if you are driving without touching the brakes and they are untouchable , something is wrong... but .... with new calipers it is likely the rubber boot on the caliper is not retracting and that will take a bit of time. did you have this issue before you replaced the calipers ?

[Theiceman]

also invest in a laser thermometer , there are cheap these days will save your fingers

[kenjisak]

if you are driving without touching the brakes and they are untouchable , something is wrong... but .... with new calipers it is likely the rubber boot on the caliper is not retracting and that will take a bit of time. did you have this issue before you replaced the calipers ?

dont think so, fronts were dragging instead of rears after replacing the brakes and that same time i replaced rear left caliper which piston moves freely. but fixed that , problem was slide pins and boots were seized. but awhile after that car started feeling slugish and noticed the rears were hotter than the fronts now instead.

Sent from my SM-N950W using Audizine Forum mobile app

[Theiceman]

So you have only replace one caliper at the back or both ?.
And with new or breaker yard units ?
I rebuild the calipers on my 911 and had this issue for about a week..
The rubber bellows was stopping the caliper piston from sliding back in.
Once it was a little used it was fine

Sent from my SM-G973W using Audizine Forum mobile app

[kenjisak]

So you have only replace one caliper at the back or both ?.
And with new or breaker yard units ?
I rebuild the calipers on my 911 and had this issue for about a week..
The rubber bellows was stopping the caliper piston from sliding back in.
Once it was a little used it was fine

Sent from my SM-G973W using Audizine Forum mobile app

what are breaker yard units? i did grab one from a scrap yard and replaced it with that. i used the old electric motor from the old caliper. i was planning to rebuild the rears in the spring if this issue doesnt get fixed this winter. that and replace the hoses with braided lines.

Sent from my SM-N950W using Audizine Forum mobile app

[kenjisak]

also invest in a laser thermometer , there are cheap these days will save your fingers

yee sure thing. ill try to measure the temps and report back

Sent from my SM-N950W using Audizine Forum mobile app

[Theiceman]

Yes a breaker/scrap yard . They should work fine . Should not have any drag at all.
The one thing I have no experience with on these cars is the electric parking brake.
Other than that I have no idea.
I could compare for you with my car next time out. But I don't drive it that often

Sent from my SM-G973W using Audizine Forum mobile app

[kenjisak]

Yes a breaker/scrap yard . They should work fine . Should not have any drag at all.
The one thing I have no experience with on these cars is the electric parking brake.
Other than that I have no idea.
I could compare for you with my car next time out. But I don't drive it that often

Sent from my SM-G973W using Audizine Forum mobile app

yeaa they didnt at first. but both sides drag i feel. this is my first electric parking brake and so far im not liking it xD id still prefer the ol ebrake cable over electric anyday. less variables for problems and just prefer it in general

Sent from my SM-N950W using Audizine Forum mobile app

[Theiceman]

Maybe someone who is more knowledgeable may chime in, butbibwonder if they have to be adapted somehow. ( The rear parking brake )

Sent from my SM-G973W using Audizine Forum mobile app

[morris39]

So used parts of unverified copmpatibility replaced by someone inexperienced in that area. This maybe should have been stated upfront? How useful can advice be w/o that?

[Theiceman]

So used parts of unverified copmpatibility replaced by someone inexperienced in that area. This maybe should have been stated upfront? How useful can advice be w/o that?

calipers are pretty plug and play ... people with zero experience do them successfully... not sure it applies here.. especially both sides, something else is up in my mind .

[kenjisak]

So used parts of unverified copmpatibility replaced by someone inexperienced in that area. This maybe should have been stated upfront? How useful can advice be w/o that?

ive replaced calipers before. i also kept the same electric motor that was originally in the car just in case if electronics might go wonky. also if it was just the caliper that i replaced that was dragging i wouldve figured it out quickly and go ahead and replace it again. but both sides are dragging and the caliper i used to replace is in much better condition than the other side so dont understand why it would drag. other than the e brake not being calibrated properly which i hope is the case but i cant find any info on how to do that.most point to the direction of the cae being able to auto calibrate its brakes itself .i used carista for brake jobs as well

Sent from my SM-N950W using Audizine Forum mobile app

[kenjisak]

calipers are pretty plug and play ... people with zero experience do them successfully... not sure it applies here.. especially both sides, something else is up in my mind .

i replaced the brakes in august and ive done about 20k km, and the fronts were measured at 10mm and the rears were 7mm when i went for an alignment a couple days ago. do you think the rears are wearing too fast?

Sent from my SM-N950W using Audizine Forum mobile app

[A4B8 2.0tfsi]

Just redo the e-brake pad change sequence, and see if that cures the issue, but if none of the three?? workshops haven't already done it, well...

How did you change the motors? Proper sequence or just replaced them and nothing else?

[kenjisak]

Just redo the e-brake pad change sequence, and see if that cures the issue, but if none of the three?? workshops haven't already done it, well...

How did you change the motors? Proper sequence or just replaced them and nothing else?

serviced the rears a couple times and whats the proper sequence for the motors?

Sent from my SM-N950W using Audizine Forum mobile app

[BrianVan]

The simplest solution is usually correct. As several had said, the slide pins are probably not retracting enough or one is stuck. If the ebrake was engaged, or even slightly, it would be smoking the pads. No brake shop will go thru the effort any of us would for our cars. One has to remove the pin rubber boots, (they should be really be vacuum sealed on there) and should "pop" off. Pull the pins...sand them down to a shine, and get a wire bristle brush and scrub inside the pin holder "hole" or drill wire brush in there of course with a cheapo Freight Harbor pencil size wire brush. Then lube them up with high temp grease, any will do. Like the above comments, anyone can change the brakes with minimal wrench skills, but the extra effort is what counts. No shop will do that as they are "book time". In and Out.....with your 10yr old car and harsh Canada winters, (salted roads??). either way...A rusted pin doesn't release any slight pressure from not releasing will cause that heat. Maybe the now winter cold will keep them cooler (lol), but I'd hate to do that work in the freezing cold...

[kenjisak]

The simplest solution is usually correct. As several had said, the slide pins are probably not retracting enough or one is stuck. If the ebrake was engaged, or even slightly, it would be smoking the pads. No brake shop will go thru the effort any of us would for our cars. One has to remove the pin rubber boots, (they should be really be vacuum sealed on there) and should "pop" off. Pull the pins...sand them down to a shine, and get a wire bristle brush and scrub inside the pin holder "hole" or drill wire brush in there of course with a cheapo Freight Harbor pencil size wire brush. Then lube them up with high temp grease, any will do. Like the above comments, anyone can change the brakes with minimal wrench skills, but the extra effort is what counts. No shop will do that as they are "book time". In and Out.....with your 10yr old car and harsh Canada winters, (salted roads??). either way...A rusted pin doesn't release any slight pressure from not releasing will cause that heat. Maybe the now winter cold will keep them cooler (lol), but I'd hate to do that work in the freezing cold...

sure ill try this. i did make sure to grease the pins and they werent rusted at all and serviced the rears a couple times. i made the mistake of putting too much grease to the point where the pins push out and that cause even more drag. but i didnt take a wire brush to the inside of the the slide pin hole so ill try it out when it gets a bit warmer. ottawa weathers bipolar and its about -15 rn but might get closer to 0 sooner.

Sent from my SM-N950W using Audizine Forum mobile app