Is your steering wheel quakin' in its boots? Tie the laces!
The newest BMW E46 is now 10 years old. Many are older. These cars are built to high standards but they're also built as light as possible with light and sometimes thin materials. These can make it easy for slight imperfections to cause strong vibrations. The easy answer is to replace everything. But some are on a budget. So you'll have more work to do. It's important you fully maintain the suspension and verify the maintenance and operation of your vehicle. The basics of this apply to any car.
If your vibrations start around 60mph and get worse as you go faster, this is typically the result of poor balancing. You may say, "But Mango! My wheels ARE balanced." Try another shop. Not all balance jobs are created equal. Some shops do not regularly calibrate their machines. Yes, the machines that balance your wheels need to be "balanced" themselves. Go to a larger tire store for this as their equipment is more likely to be kept-in-check. Don't rely on some small shop all the time. Some people prefer road-force balancing where a load is placed on the wheel to replicate its intended use.
OEM wheels are your best bet as far as avoiding vibration. The reason is OEM wheels are hub-centric from the factory and this makes easy to center correctly prior to applying a clamping force (torque) to the wheels. Also be sure to thoroughly clean, and if necessary lightly sand, all mating surfaces. This includes the wheel mounting face where it touches the hub and the hub surface itself. There should not be any corrosion at this interface. It must be medical-grade clean for full safety and vibration free driving. Check periodically as corrosion can build. The corrosion could crush which would reduce the biting area of the wheel to hub. This can be dangerous. If you have aftermarket wheels, try purchasing the appropriate sized wheel mounting rings (aka hubcentric rings) to assist in centering the wheels. These, as far as I know, are not crucial to the loading of the wheel, but simply to assist in centering the wheel only. If you feel you need them for safety, by all means, buy them. Make sure wheels are true and round with no damage or bumps. Make sure the wheels are evenly torqued down in a star pattern using proper fasteners and torque values. 90 lbs is what I use. Make sure your torque wrench is accurate.
Needless to say, make sure your tires are of high quality and name brand. Make sure there's no bubbles or high or low spots on the sidewall or tread itself. Newer tires are better. Ensure they are inflated to the proper pressure and there's no flat spotting from donuts or track driving.
4) Control Arm Bushings
50k miles or you don't know how old they are, replace them. If visually worn, replace them. If there is movement in them when the wheel is grabbed, replace them. If you get a clunk when you tap the brake sharply, it's the control arm bushings usually. Replace them.
5) Control Arms
These have balljoints. Replace them if damaged or broken or loose.
I don't see these as a common cause for vibrations but I suppose in theory, it could happen. Replace them.
7) Wheel Bearings (at the request of the two posters who mentioned)
A wheel bearing can also cause vibrations. Particularly, you will hear a low rumble get louder as you turn left or right as the bearing is loaded up.
If your wheel shakes as you brake, all the above could contribute, however you might have Bunk Brakes. But Mango, I've replaced my brake pads and rotors! Ohh, did you now? Well I ask this. What brand? If you used low quality aftermarket, or aftermarket products generally perceived as "good" but suck anyway (BammerBrasCo, eBay, Autozone brand, Poodleman Drilled and Spotted and Dotted etc), then yes they can cause your brake shakes. What causes brake shakes, Mango?
Not warping. Not that rotors CAN'T warp, it's just next to virtually impossible. Particularly with our large rotors. The problem is PAD DEPOSITS. With quality brake parts, it's HARD to get pad deposits to the point of causing brake shakes. CrappyBoy pads can overheat QUICKLY causing DEPOSITS to form. This is why your generic BunkBoy pads caused deposits which caused vibration.
QUALITY BRAKE PARTS ONLY, ya hear?
Here are my recommendations for brakes. Check yourself to see what works best for you.
BEST: Genuine BMW Factory Pads and Rotors
Very good: Brembo, ATE, Jurid
Acceptable: Meyle, Stoptech, Zimmerman, BMW Performance rotors
Poor: eBay generic, Autozone, BimmerBro etc. (generic BMW store enthusiast brands), anything non-BMW drilled/slotted
Also if you still get vibrations using QUALITY brake parts, you could also have a stuck caliper which is causing your pad to glaze the rotor. You can also be highlighting any other deficiencies in your suspension as noted above.
By definition, if all the above are checked, verified, and ensured, then you should not have any vibrations.
Most high-end luxury-sporty car manufacturers design their cars with balance in mind. BMW is no exception. The E46 in its day was praised the world over by fans and automotive journalists alike. The reason for this praise is due to the high level of driveability, performance, and comfort BMW struck so well for its cars, particularly the E46 model. We all know this, and by and large the reason we all bought these cars.
Now, don't get me wrong, I love modding as much as the next guy. My very own 330i had many modifications done to it, but largely those that improved the driveability or performance, but not in such a way that would have excessive detriment or cost-efficacy. Some of my favorite mods were parts that BMW designed -- M3 engine/trans mounts, M3 RTABs, M3 quad balljoints. If you can grab your mods from your manufacturer's tuner parts bin, that's ideal. You know it's tested and proven. Other favorite mods of mine are Bilstein Sport dampers. These are a superior mod over other brands like Koni for several reasons. Here's my recommendations for the following popular mods.
Our non-M M54 engines have extremely well designed airboxes. They strike an effective balance between air flow, NVH control, induction temps. You affect one, you usually affect the other.
BMW has a full engineering staff at their disposal with nearly limitless resources and secret internal supercomputer-derived data on which they design their powertrain systems and sub-systems on. The stock intake is the business! The filter element used is more than large enough for the demand placed on it by our 2.5 and 3.0L engines. The stock intake is designed to pull in cold air with a ram air effect. Our engines are maximized for efficiency at low to mid RPMs in concert with VANOS and the DISA and as such, the intake is tuned with this overall system in mind. You wouldn't want to break up BMW's symphony, do you? Low to mid RPMs is the M54's happy spot. Why screw with that? Your VANOS, DISA, and manifold design work in harmony to provide low-mid range grunt and response and you want to throw a curveball into that with your untested filter on a stick? Any $200-300 intakes you buy (assuming it's a well designed one) may give you 1-3hp at the very top of the rev range at redline, but you'll likely suffer a bit at low RPM, particularly with throttle response as one of my good friends experienced with his high end < Insert popular expensive intake brand here >. The lesser of the evils is the BMW performance intake where it's said to make a good sound--however the draw back is these have been known to go over $1,000. With many aftermarket intakes, you have the threat of ingesting water and hydrolocking the engine. And finally, many are illegal, particularly in California. Is that expensive intake worth it for the added noise and attention from cops it just brought you? In my younger modding days, I had a cop ask me to pop my hood before. It's not fun! I've also removed my fair share of aftermarket intakes for E46 members here. In short, they got tired of the added noise, fitment issues, constantly having to jerk them off to stay on the car, etc. Most of all, they hated the throttle response.
Drop in dry filter from high end company
BMW Performance Intake
K&N or anything oiled
All aftermarket intake systems
Exhausts and headers
The stock system is well designed including heavy duty corrosion resistant materials and double wall design. And if you delete the stock butterfly valve on 330 models, you can get a nice deep rumble if you desire a sporty sound and maximum flow! If you must mod, go with stock ZHP exhaust which includes butterfly delete and different tips! The muffling chamber also creates a nice sound as well. As far as headers, only stock. If you must mod, pull from another BMW model. The point is you need high quality BMW parts with stock cats. Do the responsible thing for the environment! Also stay legal and avoid headaches.
Anything aftermarket* (Unless your car is full time race car or your state has no applicable laws or restrictions) Not worth it.
This type of mod I believe has a larger window of cost-effective modding. The stock suspension is wonderful beyond words. Strikes a nice balance. But particularly on non-M models, it's a bit more on the comfort side but still plenty capable especially with sport models. Believe me, I had a sport E46 brand new from the factory. Sublime handling! Go with BMW ///M or ///M3 parts if possible!
Stock BMW sport
Rogue Engineering (RSM)
(May have missed a few big/high end names but you get the idea)
Any generic stuff from ebay including those aftermarket R9, TR, GH, or whatever coilovers kids use. They've been known to bust welds while going 90 mph and flip BMWs over. Not to mention perform like poo. Stay away from generic. Any other unknown custom "enthusiast" put together kits unless those parts are publicly listed online so we know how safe it is. You see stuff from certain stores that make you scratch your head, sometimes they throw in meh stuff with good stuff?
I'll quote the takeaway here: For 99.99% of your driving, the stock BMW brakes are optimum, in my opinion. Sure you can get some race pads and gain marginal increases in pedal feel, consistency namely after high-speed repetitive stops, but for a daily driven car, consider that these upgraded "race" brake pads may not provide the consistency and quality of braking stock pads deliver, particularly in "cold" temperatures you will normally see on the street.
The last thing you want is to T-bone a car that pulled out in front of you on the way to work because your "race" pads needed 10 repetitive stops on the track in order to become immediately effective. Race pads also tear into rotors and make a ton of noise. There's usually a price to pay when you gain performance.
These are my personal recommendations on these BMW E46 brake parts:
BEST: Genuine BMW Factory Pads and Rotors Very good: Brembo, ATE, Jurid Acceptable: Meyle, Stoptech, Zimmerman, BMW Performance rotors Poor: eBay generic, Autozone, BimmerBro etc. (generic BMW store enthusiast brands), anything non-BMW drilled/slotted
Keep it stock or go with the pre-designed direct plug and play system by popular companies. I think the name starts with a B?
Stay away from those dyna-whatevers, android whatevers, and cheesy single din-enclosures. I stayed stock and installed an adapted aux interface and called it a day.
Everyone obviously can spend their money how they want. But I would say here are...
Mango's rules to modding!
1) Spend wisely. Make sure your mods are worth it relative to what they give you. On a performance car, you should emphasize performance. Does $300 get you 3HP? Ask yourself, "is it worth it?" That's money you'll never get back. At least make sure it delivers a return on performance!
2) Stay legal. Not worth risking spending even MORE money on top of already poorly spent money when you get a ticket and have to face a judge.
3) Stay responsible. Your mod might be cheap and legal, such as heavily stanced and cambered wheels. But it may not be responsible. Are you risking spinning your E46 out of control as soon as your overly stiff, overly low, overly wheeled and tired, and overly cambered E46 spins into a tree or worse yet, into a family of four? Remember your choices can affect others.
When servicing your E46, be sure to follow proper procedures! Many love this BMW service manual--rave reviews
This blog post is for you if you just purchased your E46 3-Series and/or have more than 75,000 miles on your current cooling system on your E46 3-Series BMW.
The BMW E46 3-Series is among certain BMW models that are known to to suffer from cooling-related failures, often times catastrophic due to warping the engine block.
The 6-cylinder in your E46 is a straight six design featuring an aluminum head and block. This design has inherent benefits for which BMW engines are known for. However this design also has inherent drawbacks. When overheated even for seconds, the long aluminum head on a BMW straight six is particularly vulnerable to warping. The fix is a risky and costly top end engine rebuild or a complete engine replacement. The cost is $3,500 and up.
When a BMW 3-Series overheats, the result is usually a blown headgasket causing coolant consumption, coolant/oil mixing, or an overpressure situation in the cooling system. Either way, the car will not run long during any of these three conditions. This happens to so many people on a daily basis but can easily be prevented with $500-750 worth of parts every 75,000 miles.
As such, it is absolutely imperative that you maintain your BMW E36/E46 3-Series cooling system.
If your temperature gauge does go into the red zone, shut off the car immediately and have it towed.
BMW E46 Complete Cooling System List 9-26-16
Mangos Engine including Rebuilt Cooling System
Here is the complete parts list or you can just go to the Amazon e-store I set up to have them all ready to go!
Alternative:**Thanks To Terra, you can also buy BMW X5 part for your hydraulic tensioner. #11287549557 it comes with a backing plate you won't be using. Discard it. Just reuse your bolt** Link to buy X5 A/C Hydraulic Tensioner Pulley
Automatic Transmission Cooler O-Rings. (Highly recommended as the old ones tend to not seal the same) Order two of these for the transmission cooler.
OEM link to buy
Prices, information, and brands/prices/links subject to change. These are current as of 9-25-16 The total cost for manual cars is around $500. For automatic cars, around $750 which includes the fan blade/clutch.
Read about the individual parts below or skip straight to Amazon where I've put together a list of cooling parts. These are some of the best prices I've found and most if not all parts are available with free prime shipping.
How, why, and when do the failures typically occur?
The number one cause of cooling failure for the E46 3-Series is the expansion tank. This tank has a 100% failure rate and fails on every single E46, usually around or before 90,000 miles. This can be installed in your driveway in 45 minutes or less using simple hand tools. If you can change a light bulb, you can change your expansion tank.
Some fail sooner than that while some last longer. These tanks fail because of heat cycling of the plastic material they are made of. Typically the failure will make itself known when you see a yellow low coolant light on your gauge cluster. You will open the hood and the tank will look fine but what you don't see is the hairline crack that formed down the side of it, usually invisible to the naked eye. This crack expands under pressure and water spews out either while driving or when the car is parked. Come back to your E46 and there's a puddle under it? Yep that's your expansion take 9/10 times. If the water/coolant level becomes low enough, there will not be enough coolant for the water pump to circulate. No circulation means no flow through the engine/radiator. No flow through the radiator/engine means overheating and a $5,000 engine replacement and lost down time, towing fees, rental car fees, headaches, etc. Again, buy here. DO NOT BUY THIS AFTERMARKET IF OU CAN AVOID IT. GENUINE BMW ONLY. Genuine BMW is maybe $20 more but it's worth it. If you do not buy Genuine BMW, you may buy OEM which as of time of writing, is the brand CoolXpert.
If you just need the expansion tank cap, buy here. It's good to keep a spare cap or replace at 25,000 mile intervals because the seals on the cap are known to harden and lose their ability to seal, even between tank replacements. They're around $12 -- good investment.
Pulleys and belt(s) systems
Our M5X and S54 engines have three belt-driven tensioner pulleys. The role of the tensioner is either to provide belt-spacing/traction and to quell crankshaft vibrations due to irregular accelerations from the crankshaft. This is done to prolong the life of belt-driven accessories and likely to quiet engine operation.
When should you replace your pulleys?
If your pulleys are original: replace them.
If you don't know how old they are: replace them.
If they are noisy or have excess play: replace them.
If they have 60,000 or more miles: replace them.
This is a crude diagram of the front of an M5X engine:
The main belt drives the water pump, alternator, and power steering pump. This belt is guided by pulleys. These pulleys contain ball bearings and grease. After around 60k miles, this grease dries up and the pulleys are vulnerable to failure. The belts are then thrown off once this pulley fails and you now have no cooling system, no power steering, and no charging system.Your dashboard will light up like a christmas tree and your temp needle will fly into the red zone.
Belts. Obviously the belts themselves can fail causing an otherwise brand new cooling system to not operate. Replace every 35k miles. You can find it here.
This belt system is no joke. E46s are prone to pulley failure. I've seen it time and time again. Is your E46 squealing and whistling? Replace your pulleys. They're cheap and very easy to replace.
The water pump is another potential failure point but admittedly not as common. It can fail in at least three ways. 1) The impellar itself will break and cannot continue to push water. 2) The seal may leak and, 3) The bearings will fail causing the shaft to wobble and break which will in turn throw the belts off effectively rendering your cooling system useless.
You might hear nightmares of water pumps with plastic impellars, but don't pay attention to this. Replace your water pump due to age and/or mileage, not because what its made out of. The latest BMW water pump design (at least 10-15 years old) features a plastic composite impellar. BMW did once try metal impellars but quickly phased those out due to premature balancing and bearing failures. Design is more important than physical materials. Some people insist on installing the Stewart water pump. Some recent reports suggest that these are low-volume production items and may fail prematurely. Others report success. It's up to you. If you insist on the Stewart water pump, it can be found here.
You'll need to remove the fan on your automatic E46 to access the water pump. I recommend this fan clutch tool here: http://amzn.to/2dWyHTU
Generally fails in the open position leading to a "cold" temperature needle on your gauge not allowing the car to warm up, this item can leak as well or worse yet, fail closed or partially closed. It's a good idea to replace it. Thermostat can be found here.
The E46 radiator is typically robust, but the end tank seals are rubber and harden over time. You'll notice staining or slight weeping. The radiator has thin passages which can become clogged with sediments as well and may cause water to flow slowly to where it needs to go. This may cause problems in traffic or while stopped. The plastic end tanks may also fail but this isn't that common of a failure mode for this part. They are cheap enough to replace anyway and is one of the most vital cooling parts--arguably the most important one. Don't skimp on this. Manual Trans unit here and Auto Trans unit here.
Fan blade and clutch
(for automatic transmission equipped vehicles).
Another failure point. If the blade chips or deteriorates, there goes its balance and will explode in your engine bay. There goes your belts, hoses, hood and whatever else it feels like taking out. The fan clutch is typically robust, but is good practice to replace it anyway. It controls the speed of the fan. You don't want it spinning too slowly or too quickly. A fan that cannot blow sufficient air over the radiator will fail to cool the water/coolant and thus the car will overheat. This typically happens when the car is stopped in traffic, say at a red light.
BONUS - WHY IS YOUR E46 OVERHEATING?
Written specifically by Mango
In order for your car to not overheat, these basic requirements have to be met:
1) Cooling system must be filled to capacity. That is to say the system must have no leaks and no air bubbles or pockets in it. Car must have correct amount of coolant/water.
2) Water must be able to be driven without any unnatural hindrance. That is to say the water pump must be able to push water throughout the system without added blockages or weakened drive force due to a damaged water pump or slipping/missing belt. The thermostat should also be opening and closing as designed.
3) Air must pass over the radiator in sufficient quantity at the correct moment. That is to say your mechanical and/or electrical-driven fans must be operating correctly when triggered by properly working sensors.
If your car is overheating, at least one of the above is not being met or you have bigger problems with the headgasket (unlikely if you've never overheated before)
If your car is overheating at idle (say in traffic) and you are sure that 1) you have adequate water in the system and 2) said water is air pocket/bubble free, then air is failing to blow over the radiator. You need to investigate why. Either the fan(s) aren't operating properly (not blowing air or enough air) or your fan switch isn't telling the fan to turn on. (or both) Or you have debris between your radiator and condenser. Time to break out the a toothbrush and garden hose. Remember you must have proper coolant/water flow and proper air flow!! You need both.
COOLING SYSTEM INSTALL TIPS: Bleeding the system: (VERY IMPORTANT-DANGER DO NOT SKIP!!)
This step is extremely important. No amount of brand new cooling parts in the world will work if you do not bleed the system properly. The point of bleeding is to remove air bubbles/pockets. The cooling system is most efficient when it is circulating only fluid. Heat cannot radiate away from the surface of the radiator if there's air pockets. You are essentially reducing the size of your radiator significantly if you have air pockets running through it.
Here is the official procedure per BMW TIS:
Here is a quick cheat sheet on how to bleed the BMW E46 Cooling System:
Raise front of car on ramps (Not necessary, but recommended)
CAUTION: ONLY DO THIS WHEN CAR IS COOL AND ENGINE IS OFF. At no point should the engine be turned on.
1) Remove expansion tank cap and bleed screw and set aside
2) Turn ignition to ON (dash lights on but do NOT start the car)
3) Set heat to MAXIMUM (90) and fan speed to low (this opens heater valve)
4) Begin to fill your expansion tank with ideally a 50/50 mix of Genuine BMW coolant and distilled water (do not use anything else--no reason to. The proper stuff is cheap) The system might take a while to swallow the water. Massage the hoses if you think it will help. Keep pouring. Water will begin to pour out of the bleed screw hole with air bubbles. The point is to keep filling and filling until the bubbles are gone. This may take a while--be patient.
5) Once you are satisfied that a continual stream of bubble-free water is emerging from the bleed hole and that your cooling system is adequately filled, go ahead and replace the bleed screw (do not overtighten). The expansion tank will be full to the top at this point so you'll need to siphon off any excess so that the appropriate tank level can be achieved.
Congratulations! Your E46 is now ready for another 75k miles of trouble-free driving. Never will you have to worry about being stranded with your wife, girlfriend, pets or kids in the car. Never will you have to worry about posting a thread asking why your car is overheating or why your engine is stained with coolant. Never again will you have to worry. (at least for another 75k miles) :thumbsup: The mileage is just a guide. Your results may vary.
Here is the complete shopping cart for the Mango E46 Cooling Kit:
Appreciate your support by using my links. I earn a small portion when you use them and it does not affect your price at all. I also encourage you to visit E46Fanatics.com for more E46 info and news--they run a great site! Hats off to them for a great community.
There's been a rash of coil packs going out lately. Your E46 stumbling? After many heat cycles, the coil pack expands and contracts several hundreds and thousands of times causing the internals to break electrical contact. This contact can become intermittent or complete broken causing your ignition failing to deliver spark to the combustion chamber resulting in poor performance and stumbling. Replace your coil packs! Keep in mind depending on your E46, the coil packs can be different. They're either the larger square coil packs or the newer smaller rounder coil packs. The valve cover is different! These are the exact Bosch units I had on my car. Free Prime Shipping! Note I recommend replacing all SIX! At about 150,000 miles, these have just about run the course. They're smoked by heat fatigue. These WILL leave you stranded or stumbling on the freeway--ask me how I know! Heat is their number one enemy. The pre 9/02 part is also the same for all BMW E36 models. The install is easy. A small 3/8" drive ratchet and 10mm socket is all you need. A flat tip screw driver helps lift the coil plug latch off on the older models. Newer models you just use your fingers. Voila!
This blog post will help you decide what pulleys you have and what to buy based on the setup of your particular car.
Your M5X and S54 engines have three belt-driven tensioner pulleys. The role of the tensioner is either to provide belt-spacing/traction and to quell crankshaft vibrations due to irregular accelerations from the crankshaft. This is done to prolong the life of belt-driven accessories and likely to quiet engine operation.
When should you replace your pulleys?
If your pulleys are original: replace them.
If you don't know how old they are: replace them.
If they are noisy or have excess play: replace them.
If they have 60,000 or more miles: replace them.
This is a crude diagram of the front of an M5X engine:
There is only ONE part number that all E46s share (E36 S50 and S52 as well). There are some rare instances where some people have reported their car doesn't have this pulley. Always check before you buy!!
You need the following: Dayco 89133 purchased at either Amazon or your local Autozone. It may be under a different part number or name, but if you ask for an a/c tensioner for your E46, it will be the correct part.
This is how the Mechanical Tensioner Dayco 89133 pulley looks (Note the size of center bearing race)
If your A/C pulley uses a MECHANICAL tensioner as well, you'll again use the Dayco 89133 pulley.
Remember: if the tensioner is round and has a 15mm or 5/8" hex-shaped nut sticking out of it, it's mechanical and you NEED the Dayco pulley.
Both types of tensioners use different pulleys and the BMW factory installs BOTH mechanical and hydraulic tensioners for the A/C through out the E46 model years 99-06.
If mechanical, you can use a 16mm or 5/8" socket turned clockwise to ease tension on the tensioner for purposes of removing the belt. Use an extension on your ratchet for extra leverage. Safely remove belt. Then insert appropriate torx or allen-head socket into actual tensioner bolt and turn counter-clockwise to remove bolt that holds the tensioner in.
If hydraulic, you use the bolt that goes through the tensioner to both relieve tension and remove the pulley.
If you want to change the ACTUAL tensioners themselves:
Common E46 setups: One alternator deflector pulley aka idler pulley, one hydraulic pulley for the main belt, one mechanical pulley for the a/c. (That's how my setup is on my 2002 330i)
Another setup I've seen is: One alternator deflector pulley aka idler pulley, and TWO mechanical pulleys (aka Dayco 89133 pulley) I've seen this on a 2004 330ci.
Your particular setup may vary!
Links and brands subject to change! Verify before buying!
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