[niko05]

I have seen this mentioned here and on other boards. I now have almost 2000 miles on my S40 2.4i. I have noticed that it is true that the rear wheels get more brake dust residue that the front ones (a lot more). This is the only car I have ever owned that does this. Anyone know what may cause this? Has anyone changed brakes on the new S40 with any good results? On most cars I have owned, the front wheels will be almost black before the rear ones get too dirty

Also, just an FYI for those of you that may be looking at the S40. The 17" Sagittas do look really great but if you want them to stay that way, be prepared to put in some time keeping them clean. They are tough to clean due to their design. IMO they are worth it. I still get lots of complements on them.

 

[Tech]

I think the S40's are setup for more braking from the rear thats why there is more dust in the rear.

 

[Danish]

The front brakes got a shield that keeps the dust away, the rear brakes dont...

 

[niko05]

Any thoughts on how difficult it would be to add the guards to the rear wheels? Or should I just consider switching brake pads. (of course you know that just washing the wheels is not an option)

 

[Tech]

If you change the rear pads to harder pads you may not like they way it stops and there is a great chance of them squealing.
I would not install a dust sheild or anything like that it will cause the brakes to overheat and warp the rotors.

 

[Volvocular manslaughter]

Braking is of course a safety feature and I hear that S40 ABS Systems are programmed to do just that. BRAKE! and they brake well. So live with a little dust, and live a long life.

 

[niko05]

True. As to the looks, since my first post, I have started adding some Mquires wheel cleaner after washing my car to the outside of the rim. Really keeps the dust off but does not affect the breaking

 

[kuyohtay]

Rear braking in front wheel drive (fwd) cars has evolved. With anti-dive suspension geometry up front and "mechanical" or "passive" rear wheel steering (as the wheel travels upward, it turns in -or- out slightly, "steering" the car) in the rear. The engineers now have the opportunity to utilize the rear brakes more effectively. Independent rear suspension designs are now so complex - the old beam is gone and good riddance.

On older front-drive cars, as the car braked for the corner and turned in, the inside rear wheel would lift (and lock up!). Still like that but much less pronounced. Engineers have now taken advantage of fwd technology in racing and use the rear brakes much more. Because they can!!

One, for assisting in slowing down the cars in a shorter distance and two, assisting in "rotating" the car under designed circumstances. There is now much more demand on the brakes. However....

The demand is still much less on the rears than the front, hence, smaller diameter and thickness of the disk, smaller / less pistons in calipers and smaller pads for weight and cost savings to suit the "need". Relative to the front brakes that is.

But the demand is not that high at the rear and they still do not heat up like the fronts. Like Tech said, the hardness or compound of the pad is compromised for efficience under those circumstances. The pads simply have to be softer to do this work and therefore, more dust.

I've had 2 VW B5 platforms (Passat) and they did the same thing except, VW sacrificed the brake disc in their design. Very little dust, very $$expensive repairs at the rear every 25K. It seems Volvo is sacrificing the pads. Better choice, but dirty wheels. Compromise!

Keep those parts stock unless you have a racing shop engineer your solution. Compromises are made in all designs, I'll take the dust - and the slower cars behind me can eat it!!! LOL

Kuyohtay...
OHWhwhwhwhWWWWa- oowwwhh OUUAhhwwwww

 

[Volvocular manslaughter]

LOL! That's good info.

 

[niko05]

I definately plan to keep the brakes stock (they just work really well). Thank you for the info. It explains a lot and makes me realize part of the reason the S40 corners so well. I would much rather clean the rear wheels once a week than pay to have major service every 25k!

 

[scotts05s40]

I have an 05 S40 AWD, I notice more dust on the rears than other cars but not more dust than the fronts.
On a side note the S40 has EBD Emergency Brake Distribution which under heavy braking engages the parking brakes as well as the rear pads to bring the wheels to a stop in a hurry.
Yes technology has enabled the brakes on all corners of the car to be used more effectively.