[e90328isf]

Hi,

I have a 2011 328i sedan and I have owned it since new. The car currently has 84K miles

I have never replaced the drive belt and tensioner. They look to be in good shape, no cracks, etc and a couple of mechanics told me they are fine. I am a bit concerned though, so I wanted to see if there is a recommended milage/years to replace them.

Also, the BMW dealer told me that the oil in the transmission and in the differential are good for life. This concerns me as well, as both of these (especially the transmission heats up a lot). I have also heard that actually changing it can cause harm - not sure how this is possible. Any recommendations on this?

How often should the power steering fluid be changed? How about the break fluid?Thanks

[codeterrorist]

I have the same car. I had the transmission oil changed when it was 58k kilometers. No such thing as a lifetime oil. Not sure if at 84k miles would do any harm or not.

[whyzee125]

Most definitely change your trans and diff fluid. Lifetime fluid doesn't mean for an actual lifetime, but for "the life of the transmission" which will definitely be a shorter life if it never gets clean fluid. Zf makes the trans in some earlier 328's and all the 335's and they say to change it at 60k, but BMW ignores this. The reason a lot of manufacturers do this is:
1) they can claim lower maintenance costs to get the upper hand on competitors
2) some get handouts from the government for being "greener" by not recycling any oil
3) maybe I'm evil surmising but they will be replacing a LOT more tranmissions this way

The theory that it can harm your trans is mostly baseless, but could have some merit if you have a buttload of miles, like say 200k+ on factory fluid. Your clutches would be worn but all that material would still be suspended in your fluid so you'd be still having some abrasive for the worn clutches to grab onto. Putting clean fluid in could cause them to slip. You have absolutely nothing to worry about at 84k. Change it!

[Serf27]

Transmission oil change at 60k miles and fluid and filter at 100k miles.
You can do both now at 84k miles and be fine.

The belt and tensioner aren’t too much and you can change those too.

[e90328isf]

Thank you all for the replies, what transmission oil do you use? DO you buy the original one from BMW or have recommendations?

[CTinline-six]

Is this an XDrive or RWD car?

2011 328i would likely have the GM made 6L45 transmission. FCP euro has a kit for the transmission pan gasket/filter, and I used Valvoline MaxLife ATF in my 328i twice now and it shifts great.

For the differential, any 75w90 would really work, I used Redline 75w90 in mine.

There are how-to threads on here for changing the transmission fluid in the GM transmission.

[JB20DGM]

Originally Posted by e90328isf

Thank you all for the replies, what transmission oil do you use? DO you buy the original one from BMW or have recommendations?

If it's the ZF 6 speed transmission, then ZF Lifeguard 6 is the way to go. Also, for the ZF the transmission filter is integrated in the pan...so a filter change is the whole pan. FCP Euro has service kits and etc available.

[Cpet]

Originally Posted by e90328isf

Thank you all for the replies, what transmission oil do you use? DO you buy the original one from BMW or have recommendations?

The 328i would have the GM transmission. The original fluid is Dexron 6. I used BMW branded fluids for my car when I serviced transmission, differentials, and transfer case. In most situations, I stick with genuine parts/fluids. This is just my personal preference, many people here find other options that are just as good.

[e90328isf]

I have the 2011 328i with RWD and automatic transmission

[nsjames]

The dexron 6 spec is so tight that any logo'd GM approved dex 6 is fine.

at 85K I don't think you need to service the diff, but I would check the fluid level. They don't hold a lot so a minor leak over time can drain the diff.

I would 100% service the transmission.
The GM transmission family that the BMW 6l45 is based on has a severe service recommendation of 50K miles and a normal service interval of 100K miles in GM cars.

at ten years old I would replace the drive belt and tensioner due to age. The consequences of drive belt coming apart can be severe, as the N series motors are known for sucking them in through the front crank seal and then you have to drop the pan to clean it all out of there.
The conti kit was like $80 last I bought it and you need basic hand tools to do it. Take you 30 minutes.

[e90328isf]

Should I also replace all the pulleys along with the belt tensioner and the belt. I heard they get worn as well?

[krhodes1]

Originally Posted by e90328isf

Should I also replace all the pulleys along with the belt tensioner and the belt. I heard they get worn as well?

On both of my cars, the tensioner pulley was DONE by 45K miles/10 or so years. Starting to squeak, and when the belt was off did not spin smoothly at all. You don't want to risk that belt breaking! If you are going in there at all, replace it all the kit is cheap enough $83 at FCP Euro for all three bits plus the new bolts as a kit.

[krhodes1]

The theory behind not changing neglected automatic transmission oil is that the new oil will have better detergent action, which can loosen gunk and either cause things that aren't leaking to leak or not hold pressure properly, or cause gunk to go places and cause BAD THINGS to happen. But my feeling is that if the transmission fails right after a simple fluid R&R, then it was probably ready to fail anyway.

These transmissions are indeed "lifetime fill" in that you get new fluid with your new transmission, but I believe some years ago BMW updated the definition of "lifetime" to mean 100K miles. Some dealers seem to have missed that memo.

I would change it at half that if I had an autotragic, but my cars are both 3-pedal. And still got the transmission oil changed at ~45K. The wagon, which I bought new, actually got a break-in change at 2500 miles, then another at 45K.

[mainbearing]

You can refer to your maintenance schedule for the intervals. If you have the GM 6L45, 50K interval for severe service or 100K for normal service. I would change the fluid at 50K, but at 84K you are still within the normal interval. Unless the transmission is on its way out, I do not think you would have problems with varnish plugging things up at those miles.

Valvoline Maxlife ATF is what I use with the 6L45. The critical part is getting the fluid level correct. You can find filter and pan gasket kits on Rock Auto.


Filter and gasket kit, for example, from Beck Arnley:
https://www.rockauto.com/en/moreinfo...t=8600&jsn=460

ATF and filter DIY:
https://www.e90post.com/forums/showthread.php?t=573490

And the differential fluid:


Power steering fluid: you can either do a flush by disconnecting a hose (search up a DIY), or just change out what is in the reservoir every year. I pump out what is in the reservoir and just refill. Much simpler. Use CHF11s.
https://www.rockauto.com/en/moreinfo...=11395&jsn=495

If the mechanic said the belt and tensioner are fine, then inspect with every oil change and consider running to them 100K. What you need to watch out for with the high tensioner failure rate is when you see the belt start to walk off the tensioner. I changed the tensioner when the belt walked a couple of mm off.


https://www.e90post.com/forums/showthread.php?t=760380

I used INA, which is OEM and mediocre I might add. Then again it was OEM, so pinched my nose and used another one. My problem was probably the bolt the first time, but I replaced the tensioner and bolt just in case.
https://www.rockauto.com/en/moreinfo...46212&pt=11659
https://www.rockauto.com/en/moreinfo...446212&pt=8900

The mounting bolt is one-time use only. Torque and angle to spec (18 lb/ft+90). I did that with the replacement and this happened. I caught it in time seeing the belt walking off, and just replaced the bolt. I was sure I was accurate the last time, but used 17 lb/ft plus about 80 degrees this time. If the belt walked off the engine it can be ingested through the front main seal and cause an engine failure.

This tensioner bolt head (that came with a new INA tensioner) almost snapped off, and if it did I would have ended up like the member with the picture above. These aluminum bolts are problematic, including those on the engine mount brackets, oil pan and cylinder head bolts. I reused the existing (2nd) tensioner, and I probably could have with the 1st (factory) one.


Brake fluid should be change every 2 years regardless of miles, because it absorbs moisture from the air.

Originally Posted by e90328isf

Hi,

I have a 2011 328i sedan and I have owned it since new. The car currently has 84K miles

I have never replaced the drive belt and tensioner. They look to be in good shape, no cracks, etc and a couple of mechanics told me they are fine. I am a bit concerned though, so I wanted to see if there is a recommended milage/years to replace them.

Also, the BMW dealer told me that the oil in the transmission and in the differential are good for life. This concerns me as well, as both of these (especially the transmission heats up a lot). I have also heard that actually changing it can cause harm - not sure how this is possible. Any recommendations on this?

How often should the power steering fluid be changed? How about the break fluid?Thanks

[e90328isf]

Thanks all for the replies.

How do I find out which automatic transmission (of the possible two) I have in my car?

[nsjames]

Originally Posted by e90328isf

Thanks all for the replies.

How do I find out which automatic transmission (of the possible two) I have in my car?

metal pan GM
Plastic pan ZF.