50k mile maintenance: What's top priority, what can wait?

[karlskry]

Hey All- my 2015 M3 DCT just turned over 50k. Car is bone stock and will likely stay that way. I would like to get some preventative maintenance done before winter, which would be done by my buddy who is a BMW Master tech with OEM parts. Is there anything below that i'm missing, and would you move anything in the "maybe" category to "must have"?

Must have:
-New plugs
-New air filters
-Mishimoto charge pipes (worried about OEMS cracking due to age?)
-Oil/filter Change (last change was at 44k)
-Brake fluid flush
-coolant flush

Maybe:
-Full DCT service (filters, oil, pan)
-walnut blasting (no loss of power, but might be necessary for DI cars?)


Car is driven ~7k per year, spirited street driving only, no track. No tune.

[N1rve]

Your master tech buddy should advise on any other thing needed when he has the car.

[arashir]

According to the maintenance schedule you have the following at 50k:

- rear diff oil
- transmission fluid (bmw doesnt say to change for dct but I will change mine at 50k)

- spark plugs and air filter are every 30k
- cabin air filter is every 20k
- my personal oil change interval is 7500 mi as I have been advised I will not benefit from every 5k
- brake fluid is every 2 years

hope this helps

[richvalleykid]

Hello I just recently bought a used BMW M4 with just a Dinan exhaust and resonator delete .
I was told I was due for an oil change as well as spark plugs . I bought the car at 27xxx and I'm at about 34xxx and I do notice a decrease in performance .
I learned it's an electric power steering although sometimes turning the wheel I hear a moaning noise like a seesaw kind of sound or creaky bed .
Also , I'm very new to this and I really don't want to mess up my car so any advice on maintainence, handling , how to know coolant levels .
Also I recently changed my brakes because I was prompted to and the light is still on my dash .
Sorry for the bombarded post but thank you to anyone who replies

[richvalleykid]

Hello I just recently bought a used BMW M4 with just a Dinan exhaust and resonator delete .
I was told I was due for an oil change as well as spark plugs . I bought the car at 27xxx and I'm at about 34xxx and I do notice a decrease in performance .
I learned it's an electric power steering although sometimes turning the wheel I hear a moaning noise like a seesaw kind of sound or creaky bed .
Also , I'm very new to this and I really don't want to mess up my car so any advice on maintainence, handling , how to know coolant levels .
Also I recently changed my brakes because I was prompted to and the light is still on my dash .
Sorry for the bombarded post but thank you to anyone who replies

[Blancofire]

Consider keeping an eye on rear differential bushings, they have been known to crack and separate at 50k+ miles, good time to do differential fluid

[karlskry]

Originally Posted by Blancofire

Consider keeping an eye on rear differential bushings, they have been known to crack and separate at 50k+ miles, good time to do differential fluid

Done just before warranty was up last year! Also had diff fluid changed

The curious thing is my master tech buddy says the only time hes changed DCT fluid is during a clutch pack install. BMW doesnt recommend changing it. So i guess i'll be leaving it for now.

[arashir]

Originally Posted by karlskry

The curious thing is my master tech buddy says the only time hes changed DCT fluid is during a clutch pack install. BMW doesnt recommend changing it. So i guess i'll be leaving it for now.

I have not been able to find a good reason yet why not to change the DCT fluid around the 50k mi interval

[Demxsr]

To my understanding, unless you're tracking the car, DCT fluid can be changed every 100k.

When the car is completely cool it's good to check your coolant level for both engine and intercooler every now and then. Just to ensure there is no leaks. Which is not unheard of, especially for the intercooler. Which can be very serious, as the coolant gets pushed into the cylinders.

As seen here: https://f80.bimmerpost.com/forums/sh....php?t=1570544

It's kind of hard to find anything solid on coolant flush / change intervals for these cars. There are 2 methods of doing it and both are a pain. One is vacuuming and the other is draining from down low. I know a lot of place just recover the coolant into very clean containers when doing work with either cooling system and just poor it back in after the work. To ensure the car has the exact amount. Both coolant reservoir have yellow crescent moon (aka toilet) indicators. You should just see a bit of coolant covering the low side. If you have had a coolant change, just make sure you know what type of coolant was used. If you have BMW's 50/50 coolant you're good to add distilled water to top off. You can also use waterless coolant, like Evans, which should perform well and last longer in theory. If you use waterless you have drain and dry the system because any left over water will essentially contaminate the new coolant. I'm guessing everyone who has had coolant done at BMW, will have BMW's 50/50 water coolant.

I'm pretty sure these are very sealed coolant systems. I think Unless you have a leak, you really shouldn't lose liquid levels. And with the chemistry of the OEM coolant, it shouldn't lose its heat exchange potency or cause corrosion, even over a long period of use / time. I'm not 100% sure on this though.

I'm curious if anyone has tried just distilled water and water wetter for track use. I had great results with that on sport bikes, as it really increased heat exchange rates. But these cars have really robust cooling systems, so it's usually not an issue.

Other then that, Oil and Filter at every 5k for me for street use. That may seem excessive and on a bone stock car you can get away with the 10k. Heat cycling oil changes its viscosity rating over time. So I like to change it every 5k to keep the oil within spec. It's super easy to do on these cars, and like $60 if you do it yourself.

Plugs every 30k

Check cabin air filter. They're cheap so I usually change it frequently.

Check intakes. I clean mine every few oil change, but I have after market ones.

Check brake pads, Brake fluid flush is good every 30-40k unless you're tracking. check the brake lines while you're at it.

Check charge pipes, if they aren't cracked, you probably don't have to change them.

Check wheel bearings, make sure no oil is squeezing out the seals, and that the bearings aren't damaged, by sound and feel.

Check the seals/boots on the rear diff.

What are you walnut blasting?

Here is a great video that shows accelerated wear on a car from going as hard as it can for many laps around the ring. Things to look for over the course of tens of thousand of miles on our cars if you only have normal street use. But happened in a few dozen laps for them. Lol

[karlskry]

Plugs: at 50k, last service was at 25k. Going with OEM BMW Plugs (stock tune), should i replace the coils as well? No misfires or anything, just wondering if that's something that should be preventatively done?

[TopJimmy]

If no misfires you keep the same coils.