[Ph0zenstone]

Lifetime fluid my arse. This is old fluid vs new fluid at only 50K miles. It was a pain in the ass to get to the fill plug - spent 3 hours unscrewing and screwing in the damn fill plug and the actual fluid exchange took 10 minutes with my handy transfer pump. I also used more than half the bottle of new fluid so won't have enough for next time

I have a June 07 build and had to reset HO integrators using my BT Tool.

Old fluid


New fluid

[Mautofied17]

Why did it take 3 hours?

[Ph0zenstone]

Originally Posted by SickStroke6.0

Why did it take 3 hours?

Cause I have fat fingers And the space around the fill plug is so tiny

[E36graduate]

The TC is in a really tough spot.....probably in 3 hours you could have taken the transmission off like I did.

[Ph0zenstone]

Originally Posted by E36graduate

The TC is in a really tough spot.....probably in 3 hours you could have taken the transmission off like I did.

I was honestly contemplating taking off the subframe to get to the fill plug but after about 100 attempts (99 of which the hex socket fell on my face) in getting the damn 14mm hex on the plug I was able to loosen and tighten with my ratcheting wrench.

After seeing the condition of the old fluid...I will likely do it again in 30K miles

[psmitty95]

Originally Posted by phozenstone

I was honestly contemplating taking off the subframe to get to the fill plug but after about 100 attempts (99 of which the hex socket fell on my face) in getting the damn 14mm hex on the plug I was able to loosen and tighten with my ratcheting wrench.

After seeing the condition of the old fluid...I will likely do it again in 30K miles

Did you notice any difference in driving with the new fluid? Increased smoothness or whatnot?

[Ph0zenstone]

not really any difference to be honest. I see it more of a preventative measure than for restoring performance really. If i didnt change the xcase fluid this time i think it would have been toast in 30K miles. So far i have done the transfer case, front differential and rear differential fluids. Next is the transmission fluid but first i have to do the transfer case and diffs on my wifes Mercedes R350 too which is also approaching 50K

[Mautofied17]

Crap, I'm going to have to do this. How hard was the front and rear differentials? I'm feeling a writeup should happen.

[jeguth1s]

Originally Posted by phozenstone

Cause I have fat fingers And the space around the fill plug is so tiny

I don't have fat finger and it still sucked! Worst fluid change thus far...

[Yvette]

where you get the fluid from?

[Ph0zenstone]

Originally Posted by e90sexion

where you get the fluid from?

http://www.thebmwpartstore.com/ Search by part number
Xcase fluid 83220397244 - $38.76

[ajsalida]

Did anyone ever determine if letting the ECU go to sleep alleviates the need to re-code? I don't see a good reason why replacing TC fluid should require it.

[Envuks]

Originally Posted by psmitty95

Did you notice any difference in driving with the new fluid? Increased smoothness or whatnot?

I just changed mine for the 50k service and I noticed less rattle from under there at cold start. I changed every fluid on the car at by buddies Indy. It cost me $350 or so... That transfer case fluid is expensive at $50 per bottle!

[Envuks]

Originally Posted by ajsalida

Did anyone ever determine if letting the ECU go to sleep alleviates the need to re-code? I don't see a good reason why replacing TC fluid should require it.

I changed tc fluid last Friday and didn't need to do anything ecu-wise

[Fro826]

phoz - after changing the fluid in both diffs, I just spent 30 minutes on the floor under my 06 330xi and could not put my eyes on the fill plug on the xcase. Frustrating. After throwing in the towel and cleaning up the garage, I went up and got the mail from the mailbox. low and behold, there's the Bentley manual I ordered. So i turn to page 270 to see that it shows the fill plug is located half way up the passenger side of the xcase. is that where it was on your 07?

[Ph0zenstone]

Yes you have to shimmy the hex up past the subframe and somehow plug it into the fill bolt. Then shimmy up the the wrench to loosen it. It's hard to see and even harder to reach

[Fro826]

Wow, ok, thanks for confirming it. What a weird setup. It seems they really want you to take your car in for this service, or just never change that fluid.

I remember being able to see the passenger back-side of the xcase pretty easily and thinking "why is the plug not RIGHT THERE, seems like that's the most logical place to put it!" Ha! There I go again, assuming logic works into every design decision....

[Ph0zenstone]

yeh its a really bad design on the BMW. I just did the transfer case and the front/rear diffs of my wife's Mercedes R350 and it was such a breeze compared to this. It took me longer to figure out how to jack up and safely get under a 5000lb beast then to do the actual fluid exchanges. Not to mention the fluids for the mercedes were 1/3 the price of the bimmer

[Fro826]

phoz, one other question - how long can the hex driver be and still fit into the fill plug? I have the equivalent of a straight allen wrench (not an "L" shaped one), it's probably 2"-2.5" long. Do you think there's enough clearance to be able to get that into the fill plug head and not have it stick out too far to where it's hitting something? I'm just wondering if I should go buy a 14mm socket for my ratchet, or if what I have might work. What did you use?

[Ph0zenstone]

My 14mm hex was about 1". I just hammered out the hex that came with with the socket set from harbor freight. Anything longer than 1.5" might be too long because I had to get the closed end of the ratchet in to loosen it. I tried using the open end and just couldn't get enough space/leverage so had to use the closed end. If you can somehow use the open end of the wrench then 2-2.5" may work too

[Fro826]

Thanks man. Based on what you were saying about limited space and the fact that my 14mm hex is 2.375" long (on right in pic below), I went looking for a socket I could hammer out like you did. Nearest Shanghai Tools store (aka Harbor Freight) is 20+ miles away. Rather than 40 mile roundtrip, I checked my local Sears, Home Depot, Ace, and Carquest - NOBODY had one by itself. Ace had a 4-piece hex socket kit that was $42! I think not.

So, at the end of my patience looking for the tool I need, I made my own hex driver for $2.72, .

The bolt has a 14mm hex head, so that end goes into the fill and drain plugs, just like a 14mm hex socket, etc. I put 2 17mm nuts tightened together as hard as possible. For loosening, I put the 14mm head of the bolt into the fill/drain plug, and put the 17mm wrench on the nut closest to the bolt head and then lefty-loosey.

Worked like a champ on the fill plug but the drain bolt is being difficult and I'm turning both nuts instead of breaking the drain plug free, so gonna go pick up another lock-nut tomorrow and will retry. I actually think if I just had a 14mm "L-shaped" allen wrench that was 3.5" or so long, that would have worked great, but couldn't find one of those at the local stores either (I bet that would cost $42 by itself!).

You were right on the challenge of getting a wrench on the fill plug. Good Gawd.....2 to 2.5 hours to find the right combination of tools and position and FINALLY got it loose! (I kept toggling back and forth from the 2.375" hex and my homemade one and took about 2.5 hours before I figured out my tool was the best option for me).

The fill plug is way lower on the side of the t-case than I thought it was going to be, don't know how I missed it last week when I was searching for it.

I think I'm gonna see if I can find 14mm nuts instead of those 17mm ones I currently have on there. 14mm open-end wrench is a little smaller than 17mm one and that little bit of more room would probably have helped.

[Ph0zenstone]

I'm glad it worked out for you. Same thing for me...job took 2.5-3 hours and 90% of that time was spent on trying to loosen and tighten the full plug lol