2004 VW Jetta - Rear Brake System Question

[FatguyRacer]

Wow. Seems like I should be glad I got a Mk V. I did the rears on it two months ago and the only drama to be had was needing special tools to do the job.

[acalles]

Positive on them being oem. We bought the car new, and it was the first time anything in the front had been changed.

We do both have entry level models though, the GTIs and VR6s are probably better. And both cars could use a fluid flush. But that still doesn't change the fact that I'm not happy with the poor breaking.

I still can't explain why the front rotors wore so fast. I saw it once on a Honda Accord that I put non oem pads on, and they ate the rotors up. Wrong compound, the dealer told me. Understandable

GTI and Golf had the same brakes, only 337, 20th AE, GLI and R32 had bigger brakes.

Did any one turn them? thats a big no-no. they will warp and wear quick. Lots of people think I'm full of it on this one, then they go to $99 brake job down the street, 2 weeks there back rotors warped and brakes squeeling, giving me the $350 they could have given me in the first place

If your braking is sub par, and you've got the 2.0, check the vaccum line that leads to the booster, they crack and you don't get the correct amount of vacuum, so the brakes will suck.

have them flushed, you should do it every 2 years or 40k which ever comes first. I live in the desert and the fluid gets nasty after two years, if you live some place humid I can imagine there really nasty. If your vehicle has steel wheels rather then aluminum, your braking will be even worse, they don't get a lot of air threw them and get pretty hot.

[Howie]

Rotors wear faster than usual on most European cars because they use a softer cast iron with a pretty aggressive pad.  If a VW rotor has mileage on it there is no way you will machine it and not go below minimum thickness.  As far as rear brake wear goes, acalles is correct about the proportioning, many 4 wheel disc cars do not even use proportioning valves, just a fixed difference in pressure between front and rear.  Also look at the difference in brake size between the front and rear.  The back brakes do not need to be big on a front wheel drive car since most of the braking from high speed is done with the front brakes.  Smaller brakes, less unsprung weight.

Positive on them being oem. We bought the car new, and it was the first time anything in the front had been changed.

We do both have entry level models though, the GTIs and VR6s are probably better. And both cars could use a fluid flush. But that still doesn't change the fact that I'm not happy with the poor breaking.

I still can't explain why the front rotors wore so fast. I saw it once on a Honda Accord that I put non oem pads on, and they ate the rotors up. Wrong compound, the dealer told me. Understandable

The difference in rotor size between your "entry level Golf and a GTI is .3" and rotor thickness is the same, also larger than many more powerfull, heavier cars and more than adequate for stopping your car.  If you are having brake fade problems, there is something seriously wrong with your car.  Even old brake fluid shouldn't make that much of a difference in normal driving.  My guess is dragging brakes, perhaps from brake fluid contaminated with oil, binding calipers or a brake booster that is not releasing vacuum.  This would explain rapid wear, fade, and other problems. 

[acalles]

The difference in rotor size between your "entry level Golf and a GTI is .3" and rotor thickness is the same, also larger than many more powerfull, heavier cars and more than adequate for stopping your car. 

your right, I totally spaced the different wheel bearing housing on the golf and beetle, where the caliper bolts directly to the wheel bearing housing rather then the caliper bracket. they have the 280x22, the other cars had 288x25's. different pads too..

the lower end ones have a problem with leaving a lip on the out side of the rotor. I've seen lots of shops just pad slap (rather then change the rotor) with that lip, and the pad gets cought on the lip making it hard for the pads to contact the rotor fully. that'll make your brakes feel like shit too.

[OverCaffeinated]

Yes steering knucke and hubs are different. Then some golf vr6 have 312mm and the r32 has 334mm rotors.

But I think I thread jacked enough. I'm gonna flush the fluid and call it a day.

Thanks for the interesting facts guys 

[cyrus buelton]

I just confirmed with several different sources that if one Caliper is bad, there is no reason to replace the other.



Amazing how these shops are in business selling this bullshit.

[Howie]

I just confirmed with several different sources that if one Caliper is bad, there is no reason to replace the other.



Amazing how these shops are in business selling this bullshit.

Text book with hydraulics is replace both since they have equal mileage, wear and age.  This certainly made sense in the days of the $12 wheel cylinder, but today we may be dealing with calipers costing up to $600 and possibly more new that are often replaced with rebuilts of dubious quality, so it becomes the tech's call.  In the case of your relatively Golf, first I would check the parking brake cable and caliper hardware on that side.  After pinpointing the caliper, unless I had reason to suspect the other caliper might cause a problem i would just change that side.

[cyrus buelton]

Thanks everyone for your help!

Just waiting for my rotors and pads to get in, then taking it to my guy Capt Hook for the work


or

if Metallimonster wants to come over and do it...........

[acalles]

In the case of your relatively Golf, first I would check the parking brake cable and caliper hardware on that side.  After pinpointing the caliper, unless I had reason to suspect the other caliper might cause a problem i would just change that side.

FWIW, I've never had a dragging brake problem caused by the caliper. Although I did once replaced brake lines that were causing the brakes to drag, they were worn out, the rubber on the inside was cracking and would peel back acting like a check valve, causing a small amount of pressure to keep the pads contacting the rotors with more force the usual.

you'd crack the bleeder and a bit of fluid would spray out, then the wheel was free again. replaced the lines and it worked fine after that.

only time I've replaced calipers is due to leakage.

[Howie]

FWIW, I've never had a dragging brake problem caused by the caliper. Although I did once replaced brake lines that were causing the brakes to drag, they were worn out, the rubber on the inside was cracking and would peel back acting like a check valve, causing a small amount of pressure to keep the pads contacting the rotors with more force the usual.

you'd crack the bleeder and a bit of fluid would spray out, then the wheel was free again. replaced the lines and it worked fine after that.

only time I've replaced calipers is due to leakage.

Exactly why I said check everything else first.