[awon23]

What's up guys. I've racked up about 65k miles on my 435i GC. Just recently flashed it to MHD stage 1, so I know I need to upgrade the charge pipe as soon as possible. Anything else you guys would have replaced?

I heard water pumps usually give at about 80k, so I'm thinking about that.
Also looking at the VRSF intercooler.

Any input is appreciated. Thanks!

[johnung]

Originally Posted by awon23

What's up guys. I've racked up about 65k miles on my 435i GC. Just recently flashed it to MHD stage 1, so I know I need to upgrade the charge pipe as soon as possible. Anything else you guys would have replaced?

I heard water pumps usually give at about 80k, so I'm thinking about that.
Also looking at the VRSF intercooler.

Any input is appreciated. Thanks!

Rear differential fluid, automatic transmission service (use ZF Kit), spark plugs. XDrives need front differential fluid and transfer case fluid.

[johnung]

Originally Posted by johnung

Rear differential fluid, automatic transmission service (use ZF Kit), spark plugs. XDrives need front differential fluid and transfer case fluid.

Change out this hose before it bursts

[johnung]

Originally Posted by johnung

Change out this hose before it bursts

Change out this hose. It deteriorates from the inside out and could fall apart in your hands

[thejeremyman9]

Originally Posted by awon23

What's up guys. I've racked up about 65k miles on my 435i GC. Just recently flashed it to MHD stage 1, so I know I need to upgrade the charge pipe as soon as possible. Anything else you guys would have replaced?

I heard water pumps usually give at about 80k, so I'm thinking about that.
Also looking at the VRSF intercooler.

Any input is appreciated. Thanks!

There's several threads on this, just do a quick search... also check the maintenance section of the forums where most of this content lives. https://f30.bimmerpost.com/forums/fo...437&order=desc

[BoyOhBoyyy]

Originally Posted by johnung

Rear differential fluid, automatic transmission service (use ZF Kit), spark plugs. XDrives need front differential fluid and transfer case fluid.

Great info! Curious to hear what's the recommended interval for rear diff fluid change?

[awon23]

Just got my car back from the mechanic. I asked him if it was necessary at 65k and he told me to start thinking about it at 80k

All in all I got my brake fluid changed, had the transmission oil drained and filled, and an oil change for $440 out the door.

[DreamerJoe]

Originally Posted by johnung

Change out this hose before it bursts

definitley replace this part, mine snapped too and there is a whole thread of people that this has happened to if you search the forum for "PSA". part cost me like $40 at the dealership, but will cost you less online if you do it as preventative.

[thejeremyman9]

Originally Posted by awon23

Just got my car back from the mechanic. I asked him if it was necessary at 65k and he told me to start thinking about it at 80k

All in all I got my brake fluid changed, had the transmission oil drained and filled, and an oil change for $440 out the door.

Just drained the trans without replacing the pan? Are you manual or uato?

[awon23]

Originally Posted by thejeremyman9

Just drained the trans without replacing the pan? Are you manual or uato?

Auto. Bad idea?

[DreamerJoe]

Originally Posted by awon23

Auto. Bad idea?

I think the pan has the filter integrated into it, places like fcp euro sell a kit that comes with fluid and pan. but I'm a 6mt guy, so their may be more to it.

[thejeremyman9]

Originally Posted by awon23

Auto. Bad idea?

Perhaps not a bad idea, but you want to replace the pan at the same time, because as mentioned above, the filter is built into it. You most likely only got a small portion of the total fluid out, and are still running with the used filter.

[johnung]

Originally Posted by awon23

Auto. Bad idea?

Is your mechanic a BMW shop mechanic or just a general mechanic at some shop?

A BMW automatic transmission service is a lot more expensive because the parts are more expensive AND because the procedure is more than just drain and fill.

Maybe/hopefully he said that he did the transmission and didn't really do it. If you just drain and fill this transmission it could be underfilled which could ruin the transmission.

IMO I wouldn't drive the car until you talk to him and find out exactly what he did or didn't do with your transmission.

The procedure calls for actually running the engine while it's on the lift and measuring the temperature of the transmission fluid during the fill process. See the newtis website for details.

The service calls for replacing the transmission pan and filter. See photo for ZF service kit. ZF makes the transmission for BMW.

Check BimmerShops website for local BMW mechanics. Call and see what they would charge for an automatic transmission service.

[johnung]

Originally Posted by BoyOhBoyyy

Great info! Curious to hear what's the recommended interval for rear diff fluid change?

The rear M Performance Limited Slip Differential is supposed to replace fluid every 30k miles, so I would expect at least every 60k miles for a standard rear differential.

I personally would do it more often. It's a very easy suction and fill service that can be done at the same time as an oil change. It takes only 1 liter of fluid. I wouldn't let a mechanic use just any fluid- only the exact BMW Fluid. BMW sells several differential fluids and part numbers have changed. FCP Euro sells the BMW fluids.

If you have an xDrive, the front differential takes 1/2 liter of its own fluid and the transfer case takes 1 liter but only about 1/2 liter can be suctioned out at a time. Both of those take a little more labor to remove bottom panels to gain access.

[F32Fleet]

Originally Posted by BoyOhBoyyy

Great info! Curious to hear what's the recommended interval for rear diff fluid change?

Rear differentials are lifetime. They simply don't fail. BMW did away with the diff change about 20 yrs ago. Change it if you want but the rest of the car will fall apart before the rear differential gives up the ghost.

[Liandri]

Originally Posted by F32Fleet

Rear differentials are lifetime. They simply don't fail. BMW did away with the diff change about 20 yrs ago. Change it if you want but the rest of the car will fall apart before the rear differential gives up the ghost.

Nothing is lifetime. My rear diff fluid looked like hell at 23k when I sucked it out. Why it looked like crap, and whether or not it would have gone 100k miles we could guess all day, but I personally sleep well at night knowing my fluids are clean and changed and I've done every bit of preventative maintenance one could do. To each their own however, and not everyone's financial situation is the same which can also guide opinions and practices

[awon23]

My mechanic told me he just did a drain and flush because he didn't think my car needed a flush at this time. He's BMW only mechanic if that means anything.

Hopefully he didn't mess my baby up....

[Liandri]

Originally Posted by awon23

My mechanic told me he just did a drain and flush because he didn't think my car needed a flush at this time. He's BMW only mechanic if that means anything.

Hopefully he didn't mess my baby up....

I assume you meant to say he did a drain and fill, you don't flush these transmissions. That's fine, drain and fill is 7ish quarts. The pan is the filter assembly and magnets though. I would have changed the pan at your mileage personally. You could still have him do that, since the total capacity is somewhere around 14 quarts, if you go back and have him do the pan then you'll have put 14 quarts and the filter in and can call it a day. Up to you of course

[thejeremyman9]

Originally Posted by awon23

My mechanic told me he just did a drain and flush because he didn't think my car needed a flush at this time. He's BMW only mechanic if that means anything.

Hopefully he didn't mess my baby up....

He did a drain and flush because he didnt think you needed a flush? lol.

Assuming he followed the proper procedure for the fill and whatnot (and fluid is therefore at the correct level) then he probably didnt mess anything up... but he basically did half the job without doing the pan/filter.

If you go back and do the pan now, of course refilling with fluid following procedures, then you should be good and will have likely gotten even more "new" fluid in since you will have essentially drained twice, and you never get all the fluid out when you do a pan and fluid refill.

Originally Posted by Liandri

I assume you meant to say he did a drain and fill, you don't flush these transmissions. That's fine, drain and fill is 7ish quarts. The pan is the filter assembly and magnets though. I would have changed the pan at your mileage personally. You could still have him do that, since the total capacity is somewhere around 14 quarts, if you go back and have him do the pan then you'll have put 14 quarts and the filter in and can call it a day. Up to you of course

Correct, ZF themselves call for 100k km, or about 62k miles, as the service interval. So at 65k its a good time to do pan and fluid. No "flush".

[awon23]

Drain and fill I mean.

[F32Fleet]

Originally Posted by Liandri

Nothing is lifetime. My rear diff fluid looked like hell at 23k when I sucked it out. Why it looked like crap, and whether or not it would have gone 100k miles we could guess all day, but I personally sleep well at night knowing my fluids are clean and changed and I've done every bit of preventative maintenance one could do. To each their own however, and not everyone's financial situation is the same which can also guide opinions and practices

Just giving truth. Rear differentials just don't fail in these cars. I've been a BMW owner for almost 20yrs and never have I come across a BMW open differential which failed due to a lack of fluid changes. Iirc, even Mike Miller, BMW Tech guru for almost 30 yrs, has said to forget worrying about it.

All diff fluid looks like crap. It's diff fluid after all.


Do whatever you feel like doing.