Last post on Mar 24, 2013 at 10:51 AM
You are in the BMW 3-Series
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BMW 3 Series, Sedan
#29736 of 30250 Me too...
Mar 06, 2007 (3:51 am)
While I've never experienced any heat related rotor problems on either of my BMWs (they always seem to make'um beefy enough for the job), I have on other cars. Take our 1998 DGC for example, in the first 115,000 miles, that van hand no fewer than six sets of front rotors (due to heat warping), while our 2003 DGC managed nearly 60,000 miles on its first set (and no warping when I yanked them due to pad thinness). The difference? While the diameter was the same for both, the thickness of the friction surfaces (i.e. the rotor portion itself) is significantly thicker on the 2003.
Think about it this way, rotors are nothing but a big metallic thermal battery, they absorb the heat generated by braking, and then gradually (relatively speaking) release that heat, hopefully in time for the next brake event. If any one brake event over burdens the rotor's ability to store the heat, it (or they) will warp. If any series of brake events over burdens the rotor's cooling abilities, then the series of events will saturate the rotor(s) with too much heat and it (or they) will warp. Said warping happens little by little and no amount of “turning” will correct the problem, quite simply, once warped, they need to be scrapped.
For our 1998 DGC I mounted a set of cross drilled rotors that were otherwise identical to the OEM part, and now, today, a full 20,000 miles later, no warping. That's never happened before, not even once with this van. Normally by 10,000 miles a little pulsing could be felt through the pedal. By the 20,000 mile mark the pulsing was getting annoying, and by the 25,000 mile mark the van was getting dangerous. Prior to the drilled rotors I tried three sets of OEM (counting the set that came from the factory) rotors (one set only lasted 8,000 miles), two sets of top of the line NAPA rotors and even a set of Brembo solid rotors to no avail. In desperation I tried the drilled rotors (having heard all of the stories of cracking and other failures I was reticent to even give them a try), and so far at least, I couldn't be more delighted.
Getting back to BMWs in general, if my car was never to take a turn on the track, I'd stick with the OEM part. If I was to track my car and found that the rotors could still go the distance, I'd still stick with the OEM part. However, if I was to track the car and experience rotor warpage, I wouldn't hesitate for a moment to put cross drilled rotors on it.
#29738 of 30250 Re: I placed the order [kominsky]
Mar 06, 2007 (9:16 pm)
A fine choice!
#29739 of 30250 Tires - Help Please
Mar 07, 2007 (1:09 pm)
I have E46 325i with SP. I have had Pirelli P6000 on them which need to be replaced. Was thinking on getting All season performance tires since I live in the CT now where it snows. I am worried about the performance deterioration. I don't push the car hard any more but I don't want it to feel too mushy. Wanted to get opinions on how much of a performance downgrade would it be. Also, any reccomendations on Tires would be welcome. thanks
#29740 of 30250 Re: Tires - Help Please [memphis10]
Mar 07, 2007 (1:39 pm)
Personally, aI live in Seattle and last year, I decided to try out an all-season tire as an all-around solution to our weather conditions. I don't drive my BMW in snow, so I wasn't concerned with "winter traction."
I did a lot of research and chose what I think is the best all-season ultra-high performance tire on the market, the Pirelli PZero Nero. Now, after driving them through the tail end of summer, the fall, and most of our winter, I tend to think of them as "jack of all trades, master of none" tires.
OK, snow first - If you will be driving your E46 in snow, don't mess around with anything short of a dedicated snow/traction tire during the winter. An all-season tire will be marginally better than a summer tire in the white stuff, but not much.
Now, the rest of the year - The decision between summer and all-season tires should be based on how hard you will drive, and how long you want your tires to last. The performance downgrade from summer tires to all-seasons will be noticeable, but only when you're really pushing the car. On my M3, I only notice the difference during very aggressive, steady-state cornering. Turn-in, road feedback, and responsiveness otherwise feel very much the same. Since the all-seasons will last longer (better treadwear rating) and also work a better during those cold (but above-freezing) fall and winter days, then I'd say, based on your description of the way you drive, the trade-off is worth it.
Based on my research last year, I'd recommend checking out the Pirelli PZero Nero M+S (I am very impressed with them overall) and the Kumho ASX. I don't think the P6000 is a particularly impressive tire anyways, and I suspect that either of these all-season choices might just outperform your current tires.
#29741 of 30250 Intermitant oil light quick flash
Mar 08, 2007 (6:15 pm)
My 03 325i I recently purchased oil light flashed really quickly and went away. It did it again every 30 minutes or so. I than added a quart of oil and after a month it flashed for like two seconds today and not after. There is no sign of oil leaking. I sure hope it's not burning oil.
The last owner just changed the oil and had the light reset 2k miles ago. Should I be afraid of the light and keep adding oil? This is not normal.
#29742 of 30250 Re: Intermitant oil light quick flash [tnguyen74]
Mar 08, 2007 (6:27 pm)
Did you check the dipstick before you added the oil? How low was the oil level? Did you check your oil level again today? How low as it then?
#29743 of 30250 Re: Intermitant oil light quick flash [shipo]
Mar 08, 2007 (9:01 pm)
The first time I checked it and it was a little low than I added a quart. The light just came on today but I'll monitor it and check the oil tommorow.
Shipo, do you know where the cabin filter is located? Is it easy to get to to inspect for replacement?
#29744 of 30250 Re: Intermitant oil light quick flash [tnguyen74]
Mar 08, 2007 (9:48 pm)
The cabin filter is on top of the engine at the back of the engine bay (towards the windshield). There are 3 1/4-turn retaining screws. Turn them and the cover pulls off. Put in the new filter. I did mine today and it took ~5 minutes.
#29745 of 30250 Re: Me too... [shipo]
Mar 14, 2007 (7:50 pm)
Even at the track, the type of rotors is not nearly as important as pads and brake ducts to keep the brakes from overheating. At the bigger tracks like WGI and Mont-Tremblant, anything less than PFC 97 pads overheats in my E46 325i. The front rotors (11.8" I think) are simply not big enough for advanced track work but the PFC pads compensate for that pretty well ;o)