Disclaimer: Do this DIY at your own risk. Not responsible if your trans fails or you get injured.

Car: 2006 325i Step Auto 49,300 miles (I have a ZF trans., check posts 73 and 74 to see if you have a ZF or GM Trans.)

Materials:
6 Quarts Castrol Import...

How many miles do you have? That may be too long of a drain interval since there is oil left behind in the torque converter. If you are going to go that route you should see how much BMW will charge to flush the system OR bring your oil to a good transmission place that only service transmissions and let them do the flush.

104K but all highway miles. That's a good idea. Let me check with the dealership...How can I trust these guys to change it out when their tag line is lifetime oil?

The SA at my local bmw dealer told me at 100k they recommend the transmission fluid to be changed (even though the pan states lifetime). If the dealer you go to doesn't want to do it, just try a different dealer.

A local indy shop that specialize in bmw wants $250 for this job. Haven't heard back from the dealer yet.

INDY for the win!

Just got a call back from the local dealership service advisor. They recommend that I not change the transmission oil. Of course they mention the lifetime fluid per BMW spec. He mentioned that another customer tried changing the oil himself and the customer ended up bringing the car in with transmission issue. I will try to talk to the service advisor tomorrow because he left me with a voice message. I'm having second thoughts about changing the oil now.

I thought BMW changed their lifetime statement to now mean 100,000 miles. In the end, it is up to you.

By the way, I just found this. See attached BMW Service and Warranty information booklet. It states on page 7 that the Automatic Transmission Fluid must be changed at 100,000 miles. Therefore, your SA and dealer don't know what they are talking about.

Attached Images

2006_3Series.pdf (638.4 KB, 618 views)

Thanks, this is good stuff. I will share this with my SA.

Why not get the transmission up to operating temperature first before opening the fill plug? (so you don't get fluid gushing out)

side note: with all the debate of whether or not to change the transmission fluid. (I personally i feel it's unsafe, especially if there are real-world stories of transmissions slipping after a flush)
*Why not drain and fill only 1 quart of oil every other oil change.* (to put your mind at rest, especially if your only concern is that the original oil loses its effectiveness over time).

1) Yes, that is a good idea, I didn't expect it to gush.
2) This DIY is only here to help people out, if anyone feels uncomfortable DON'T DO IT. Keep in mind, this is at your own risk.
3) If you drain it, might as well drain it all the way; doesn't make sense to drain out only a quart at a time.

ATF Auto Transmission Fluid (1 Liter) Equivalent to: Shell M-1375.4
price is $18-19.00 per liter.

This vehicle calls for a Shell M1375.4 ATF which is a lower viscosity fluid than Castrol Import Multi-Vehicle ATF. Castrol Import Multi-Vehicle ATF may be used in your vehicle but the fuel economy will be slightly decreased versus the lower viscosity fluid.

Castrol Consumer Relations

Integrated filter from RM European for Pan/filter kit is $176.00

See attached ZF trans info recommends fluid change if hard driving conditions.

See attached Castrol info sheet as it relates to Castrol Import Multi-Vehicle ATF and Shell M1375.4

Attached Images

	ZF trans info.pdf (326.7 KB, 1715 views)
	Castrol ImportMV.pdf (184.9 KB, 247 views)

My fuel economy did not go down; it actually went up by 1 mpg. Not sure if it was the trans fluid or techron fuel injector cleaner.

Getting mine changed out as we speak. It was on my list of things to do, I am at 70k mi on original fluid/filter. Well after running over a metal bar on the interstate, I broke a hole in the tranny pan. Indy shop is replacing the fluid and filter/pan. At least I didn't break something that I wasn't planning on replacing. Parts and 2hrs of labor+tax will be about 700 bucks. They are using ATF that is 30 dollars a quart (gotta be OEM AFT at that price). Still better than the local dealer. I hope I can feel a difference driving.

http://www.thectsc.com/

They sell:
- genuine ZF Lifeguard6, aka OE BMW fill, Oil No. 8322 0142516. $17 bucks
- a kit w/ filter (new oil pan) and 6 ltrs of Lifeguard6, $218

ZF Documented procedures:
http://www.thectsc.com/index.php?p=p...e_id=tech_info

our tranny, steptronic rear wheel drive = 6HP19

thank me later

WoW, this is a major discovery. The kit is definitely worth it. The oil in the kit comes to less than $7 a litre. The OEM oil is normally $17 a litre. I am getting the kit when I change my filter. Too bad they don't sell the oil separately for that price too.

EDIT: After reading this discussion http://www.e90post.com/forums/showthread.php?t=363648 I think I am sticking with my Castrol Multi-vehicle ATF that I used for this DIY.

Lifeguard6= re-bottled motorcraft mercon SP, which retails in the US for: 3:99/quart. Save yourself $13 bucks/liter.

In another link you stated, "the low viscosity of Mercon SP isn't ideal for anything other than minimal commuting. " http://www.e90post.com/forums/showthread.php?t=363648

If you had the choice of Castrol Import Multi-vehicle (which is the oil that I used in this DIY), Lifeguard, or Mercon SP, wouldn't you use the Castrol oil over the other two? Note: In that same thread you stated, "The only multi spec ATF I mentioned was castrol's. Its just fine in our transmission. I love its KV 100C of 8! Not bad for mineral oil based stuff! Won't hurt our trans, and its bound to have better thermal stability that LG6."

Just had this job done at the dealership yesterday. The total came out to $319. They used about 3 liters of the fluid and replaced the transmission plug. My car has about 109K miles. I plan on doing this again at 200K mile.

Something doesn't sound right. Your transmission contains more than 3 liters of fluid. It sounds like they just drained and filled (and not flushed) which is fine if you plan on changing the fluid more frequently. Not ok if you plan on changing the fluid in another 100,000 miles.

Also curious, since the fluid is supposed to be changed at 100k miles per BMW's maintenance requirements, would that be something covered under the BMW maintenance plan?

Just show them the booklet and you should be covered.