How to Change Engine Air Filter on BMW E39 530i

DIY: Change Engine Air Filter on E39 530i and 525i. May be applicable to E46s.

Parts: 

• Mann Air Filter or Bosch or Mahle.  

Steps: 

• Open hood

• Locate air filter box on the driver's side and right behind the headlamps

• Unlatch two clips (red circles)

Location of other clip closest to driver.

• Pull air filter tray upwards.

• Remove any leaves or debris in air box.

Leaves love to hide in here

• Remove old filter from tray and install new filter. 
• The previous owner used a Napa filter which is a lot thinner than the new Mann filter on the right. 

• Install air filter tray inside air box until the two clips latch into place. 

Notes: 
One my clips would not unlatch so I had to forcefully pull the tray out. Yours may or may not require the same technique.

Please change your engine air filter yourself. The job is very quick and easy. Do not overpay at quick lube places or the dealerships.

Inspect air filter every oil change or 10-15,000 miles. Replace as necessary.

Clean air filter results in better MPG and engine performance. Do not let a clogged air filter cost you money at the pump. 

How to Change Rear Differential Fluid on an BMW E39 530i

Changing rear differential oil on a BMW E39 530i. This DIY applies to non-M E39s with the same  rear differential.

Tools:

• 14 mm hex bit socket or 17 mm.
• Ratchet for 14 mm or 17 mm hex socket.
• Oil Drain Pan. I use the Lisle Black Pan.
• Ramps, Jack and Jack Stands
• Oil transfer pump or suction gun.

Parts:

• Differential oil. I prefer Red Line 75w90 since Mike Miller (Roundel & Bimmer columnist) uses Red Line in his maintenance schedule. Buy two quarts.
• New fill and drain plugs. Part #33117525064
• Plug washers for fill and drain plugs. Part #07119963355

 Recommended: 

• Rags, gloves, respirator (differential fluid is foul smelling), degreaser or kitty litter to clean any spills. Wear old clothes that you can throw away, you do not want to stink up your house or washer with differential oil. 

Steps:

• Jack up E39 and place on jack stands. I drove up on RhinoRhamps and jacked up the rear. 
• Make sure the car is level by using the same jack stands or ramps at all four points. If you do not the same jack stands or ramps, a torpedo level will help in getting the car level.
• I highly recommend jack pad adapters to avoid crushing side plastic jack points.
• I use a low profile jack like Arcan's to avoid damage to the bumpers and rocker panels
• Use wheel chocks to prevent car from sliding while jacking. 

•  Locate the fill and drain plugs on the rear differential. See picture below

The plugs are wet because I sprayed PB blaster on them

• Remove the fill plug FIRST with the 14 mm hex bit and ratchet. You want to make sure the fill plug can be removed before the drain plug. 
• My plugs were badly rusted as the previous owner did not maintain the differential. I sprayed PB Blaster and let it soak for an hour to help loosen the plugs. A breaker bar may also be needed. 

• Remove the drain plug with the same 14 mm hex bit and drain fluid into a drain pan. Draining will take a while as differential fluid is thick. 

  

  Old and new plugs.

• Place new washer on drain plug and install. Torque to 52 ft-lbs. 

• Add differential oil through fill plug hole. Use a quart pump, transfer pump, or suction gun to transfer oil. I used about 1.5 quarts to fill my differential.

• Place new washer on fill plug and install. Torque to 52 ft-lbs.  

• Check for leaks and lower car by removing jacks, ramps, wheel chocks. 

Here are some of the tools I used for this job. 

That's it. Pretty simply job to do yourself and it is a lot cheaper than going to the dealership.

Notes: 

• Mike Miller recommends performing this service every 30,000 miles to maintain the differentials. 

• Some E39 drivers have said changing the differential fluid has stopped the humming or purring noise.

• Please be safe in lifting your E39, if you have never done it or don't feel comfortable, bring your car into the shop to have the service performed.

MTC Magnetic Oil Drain Plug

Drain plug packaging from Amazon

I pulled the trigger and bought the MTC Magnetic Oil Drain Plug from Amazon after reading generally positive reviews.

The MTC plug is the first magnetic one I have purchased and will replace the stock plug on my E39 530i. I want to clear out as much metallic flakes floating around the oil and this plug will be a good indicator by checking how much metallic junk is attached at each oil change.

There are some critics on BMW forums that say the MTC drain plug is snake oil and don't bother buying because the oil filter will collect all the particles. They may be right, but for $5 it's not a huge loss if the evidence doesn't support MTC's claims.

I have not installed the plug because I am not yet due for an oil change. I will post updates and take pictures between oil changes to see if it really works. So far,  I tested the magnet strength by picking up various metallic objects and was able to grabbed large screw drivers with no difficulty. I eagerly wait my next oil change.

Mobil 1 Super Rebate. Up to $15 Off!

Offer is valid until May 31, 2016.

$12 rebate with five quarts of Mobil 1 synthetic oil! $15 if you include a filter.

Amazon is selling the 0W-40 oil for $22.88, that is only $10.88 for five quarts! What a steal. The 5W-30 is priced at $25.47 and the oil filters around $10.

Here is the Mobil 1 promo link with details. Other shoppers say the deal is limited to 2 five quart jugs.

Mobil 1 rebate may not work on Amazon purchases. I have ordered from Walmart online and Exxon Mobil has never turned down my rebate.

Cougar Vortex PWM 120 Cooling CF-V12HPB Black Fan

The Cougar Vortex CF-V12HPB is the best 120mm fans I have purchased.

These fans replace the annoyingly loud stock fans on my Corsair H100i CPU cooler. The Corsair fans sound like jet engines on startup and scream under load. The Vortexes produce a soft whir on startup and hum at idle which is barely noticeable. It is eerily quiet on startup after being used to the super loud startup. I wish Corsair didn't cheaped out on their fans because I really like their coolers. 

I prefer the Cougars over my Noctua NF-F12 PWM because of its value ($13 vs. $20). Going with the Cougars will save a bit of money if you decide to run the push/pull setup on the Corsair coolers. They are both great and the Noctua has nicer packaging and fit, but I feel the Cougar Vortex is better all around.

I have noticed a 3-6 Celsius drop according to the Asus Thermal Radar on my Sabertooth Motherboard at idle and full load. I believe the longer and steeper blades move more air over the stock stubby Corsair blades.

I am very happy with my purchase and suggest anyone to replace the stock Corsair cooling fans with Cougar Vortexes.

BMW Transmission Malfunction Warning

BMW Transmission woes.

I was driving a E90 335i and merging onto the highway when a yellow gear with an exclamation showed up on my dash. iDrive said "Transmission Malfunction. Drive moderately and Reduced Acceleration."

The transmission was stuck in gear and would not downshift or upshift. This was particularly scary going from 75 mph to 45 mph and driving way too slow on the highway. I got off at the nearest exit and quickly pulled over. I shut the car down and then restarted and the warning went away.

Everything seems normal and I have made a service appointment at the dealer to see what is going on. The 335i is under CPO warranty. I will keep you posted on what BMW says.

Symptoms: I noticed the 335i was awkwardly shifting and slipping before I got on the highway. A month ago I was stopped at an intersection and when the light turned green, I took my foot off the brake and the car lurched forward. When I am coming to a stop on a downhill road, the car will shudder and I hear a grinding noise.

Result: Transmission fluid was two quarts low and the fault only occurred once.

BMW Oil Filler Cap Leak - E90

The seal in the BMW oil filler cap will begin to harden and deteriorate which allows oil to leak. Judging by the amount of posts I see in BMW forums, this seems to be a very common issue.

To stop the leaking:

1. Buy and replace the oil filler cap. The new cap comes with a seal. 
• Part # 11128507153 for E9X BMWs with the round oil filler cap. Earlier E90, E60, E85, and late model E46s use this square oil filler cap.
• Part # 11127509328 for earlier model BMWs with the square oil filler cap.  
2. Carefully remove the existing seal. Clean and reinstall by reversing the ring. I would only try this if the leak is very small and I don't want to spend $15.

My leaking oil filler cap:  

I changed my oil and the oil level read max in iDrive. A couple of weeks later, the oil level dropped and it didn't seem right that I would lose oil that quickly.

I noticed dried oil around the oil filler cap and oil leaking down onto the valve cover area. I pulled my oil cap and it looked like mustard. After doing some research and asking some friends, I came to the conclusion that my oil filler seal was bad and condensation was coming in and mixing with the oil and looking like mustard on the cap. I replaced the oil filler cap and oil consumption is now normal and no more weird mustard looking oil under the cap.

Below is what my old oil cap looks like and the seal that is indented. There is caked oil all around.

N55 HPFP Failure

Can the HPFP fail on a N55?

• Yes, my HPFP failed at 38,000 miles. 

What were the symptoms? 

• Very long cranks, rough idle, engine would randomly surge between 600 - 1800 rpm at idle and low speeds. The latter is particularly scary when pulling into or out of tight parking spots and the car would lurch. 

What did I do?

• I believed failing HPFP were confined to the N54 and were resolved with the N55, I was wrong. I brought my car into the dealer and they diagnosed my HPFP was failing and replaced it. My car issues went away with the new HPFP.

Why am I posting this? 

• Every once in a while I will see a post on the internet asking if the N55 fixed all the HPFP issues. I would say probably with the newer BMWs. Model years built right after N54 may still have the faulty HPFPs. 
• If you are looking to buy a used early model N55, the HPFP has a warranty of 10 years/120,000 miles and yes it can prematurely fail on you.