50K mile maitenance

[JohnD]

Well the odometer on my 2001 4.4 X5 just hit 50K so I decided to perform the following maintenance items:

- spark plugs - except for having to take the warsher reservoir out to get at the back two plugs it was fairly easy
- replaced both cam sensors - Thanks to Joe at Crevier - Good guy
- Gas filter - pain in the but
- Air Filter - easy enough
- Cleaned the MAF
- Belts
- Cabin Filter
- Oil Change - Synthetic
- Fuel additive

Overall, the truck is running pretty well... The CV boots look fine - is there anything else I might have missed?

Thanks
JD

[JCL]

Brake fluid. It is scheduled more frequently for changing than the other items you have listed, but perhaps you did it in the past year.

Also, I trust you changed the oil filter when you did the engine oil.

Engine coolant if you haven't done it recently. While doing it, consider replacing the coolant hoses (including the heater hoses) as they can go soft.

Battery if you are on the original.

And just an aside, but I recommend you be careful with the fuel additive. it is not recommended or required, and can cause other problems, but if you have a specific problem from poor quality gasoline it can help temporarily (the permanent fix is to use better gasoline).

Jeff

[JohnD]

JCL - Thanks for the input... I have seen a few threads about changing the waterpump, but am not sure if it is needed. One the E36 boards the recommended changing the waterpump every 45K, which seemed excessive. I finally changed the one in my 328IS out at 110K - not because I had to but because I figured it was on borrowed time

[Kendall]

Originally Posted by JohnD

JCL - Thanks for the input... I have seen a few threads about changing the waterpump, but am not sure if it is needed. One the E36 boards the recommended changing the waterpump every 45K, which seemed excessive. I finally changed the one in my 328IS out at 110K - not because I had to but because I figured it was on borrowed time

I'd change waterpumps when they start leaking... I changed a waterpump once as preventive maintenance and it leaked after 10k miles... Every replacement waterpump seems to last only 40-50k miles or so.. I've put on 200k + miles on a couple BMW's I owned so I would know..

[JCL]

I would not change a waterpump at 50k miles, I would wait until it leaked. I don't plan to drive my X5 to 100,000 miles, but if I did I suppose I would do a waterpump then as a PM item, considering the risk of overheating upon waterpump failure.

IMO waterpump failures often have more to do with lack of regular coolant changes (resulting in a lack of effective coolant conditioner, and resulting potential cavitation), and/or problems with belt tension (leading to bearing failure, and subsequent leakage), than with the design or manufacturing process. I don't think the waterpump on the X5 is particularly weak, but I do agree with many that the result of a water pump failure is often more catastrophic in a BMW engine than some others, so decide for yourself.

[Kendall]

Originally Posted by JohnD

Well the odometer on my 2001 4.4 X5 just hit 50K so I decided to perform the following maintenance items:

- spark plugs - except for having to take the warsher reservoir out to get at the back two plugs it was fairly easy
- replaced both cam sensors - Thanks to Joe at Crevier - Good guy
- Gas filter - pain in the but
- Air Filter - easy enough
- Cleaned the MAF
- Belts
- Cabin Filter
- Oil Change - Synthetic
- Fuel additive

Overall, the truck is running pretty well... The CV boots look fine - is there anything else I might have missed?

Thanks
JD

Differential fluid should be replaced sometime as well.

[toohotdoc]

Will changing the brake fluid help to increase the braking power (less force needed to brake)? I had changed my brakes from the stock set-up to brembo drilled rotors and got deluxe pads and the brakes are not as sensitive as before, what could the reason be, brake fluid? or something else.

[dkl]

Well...cross-drilled rotors look great and dissipate heat well, which prevents fade after repeated use. But due to the drilled out holes, it has less surface area than the stock non-drilled rotors. This is the reason for the difference in feels. If you're going with cross-drilled rotors, consider upgrading to the big brake kit (larger rotors and pads) to compensate for the loss area in the holes.

[Kendall]

Originally Posted by toohotdoc

Will changing the brake fluid help to increase the braking power (less force needed to brake)? I had changed my brakes from the stock set-up to brembo drilled rotors and got deluxe pads and the brakes are not as sensitive as before, what could the reason be, brake fluid? or something else.

Definitely, if your brake fluid is old and contaminated, a full brake flush will restore brake firmness in the brake pedal and also increase braking power.

People who race or track their cars frequently replace brake fluid...

[JCL]

I don't agree that old brake fluid has any effect on pedal feel. If you have air in the system, certainly, but you could just bleed them if that was the problem. You need to change the fluid to get the water out, which sits at the low point and damages the calipers over time. The result of not changing brake fluid is having to replace calipers when you do a brake job. Racers change brake fluid because they tend to boil it due to extreme heat, not generally an issue on the street.

The different pedal feel is most likely due to the combination of the pad material, and the friction surface of the rotor. The cross-drilling reduces performance slightly, but you shouldn't feel it. It is the surface finish that matters more.

Not sure why the cross-drilled rotors would change the pedal feel much simply due to being drilled; friction is a result of clamping force and co-efficient of friction, it doesn't depend on the surface area being clamped. I think you would get a bigger impact from the reduced thermal mass and faster overheating, if in fact you are getting fade. I read the post as different pedal feel even when cold, thought.