[fast_67ford]

"Disclaimer" This is a car lift job, i don't think jack stands would cut it. Also some pictures may show (parts) of out of sequence steps " i was figuring things out". Lastly I used what i had on hand to do this job. I'm far too cheap to buy bmw specialty tools.

Car in question- 2011 e90 328ix W/GM AT
*Make sure you know what ratio your differential is, mine was 3.91*

Parts list:
Differential (199.00 ebay)

AXLE SEAL
Part Number: 33107505601 ( 15.00 )

PINION SEAL
Part Number: 31521428678 ( 15.00 )

Differential to oil pan O-ring
Part Number: 31511213527 ( 4.00 )

Gear oil 75-90 ( 15.00 )

M12 x 1.5 all thread rod " at least 1 meter length" ( 20.00 )

M12 x 1.5 nuts x 4pcs ( peanuts )

12mm I.D. washers x 4pcs ( peanuts )

Tow hook ( free, if its still in the trunk)






First step, Get rid of all useless garbage






Next prep your used unit with all your new seals so its ready when you need it. I didn't replace the pinion seal in mine because i didn't feel like it. I used an axle bearing slide hammer to remove the axle seal.







Then persuade The new guy in with a big socket and hammer. O-ring go's on the boss on the other side.







Next remove engine acoustic cover to access the engine lift point. *Note the lift point is "tow hook thread". Then with a long extension remove the driver side motor mount bolt; Its easy to see and get to. Once this is done, install the engine support bar. The harbor freight bar needs spacers to get the right tension on the tow hook. We are just trying to support the engine from lowering with the sub-frame, nothing more nothing less.












Remove Both front tires







Remove splash shields under car








Next we need to remove the driver/passenger side cv axle and knuckle unit.
-Remove the tie rod at the knuckle
-Remove the sway bar link at the sway bar
-Remove the tension strut at the body mount ( Easy way )
-Remove the control arm at the body mount ( Easy way )
* NOTE remove these items, and just let it hang there on the strut assembly; cake.











Now it starts getting fun.
We need to pop out the driver/passenger side cv axles.
I didn't use any special tools, just some pry bars and a big screw driver.
Theirs really nothing to pry against so I cant give any helpful advice here; but I used two pry bars and my helper used a big screw driver and we got them both out. it was touch and go there for awhile.

*NOTE you need to wedge something somewhere on the passenger side after you get the axle out to keep it from going back into the differential. " I wedged a big dead blow hammer between the strut assy and the fender well."















Remove drive shaft









Remove Differential bolts and freeup from motor.









Remove driver/passenger side lower motor mount bolts













Remove sub-frame bolts and replace with all thread rod as you go; while supporting the whole assy with a transmission jack or something.
*NOTE only put all-thread support screws in 4 of the six holes, the two nearest the cabin are at an angle and will hang you up.

We need to drop the sub-frame down about 2 inches, this is so we can remove the driver side motor mount. Surprisingly the sub-frame doesn't come down as easy as you would think. I would support it with a transmission jack, loosen up the nuts on the all thread studs, lower the jack and use a pry bar to persuade the sub-frame to the nut stops. " i did this a little at a time"
*NOTE the engine shouldn't be going down with the sub-frame, if it is adjust your engine support bar!











Remove driver side motor mount. "At this point the stud of the mount should be clear of the bracket on the motor."









Now remove the front Differential. Its not easy, i had to use a pry bar and push the motor towards the passenger side to get just enough room for it to come out.
*NOTE This picture shows why you need to remove and prop up the passenger side axle.









Now install new Differential, driveshaft end first. Again its a mofo it get in, have your helper use a pry bar to move the engine over as much as he can. Then just when you cant hardly lift your arms anymore it will pop in. just like installing an n52 valve cover.








Now put everything back together, just make sure you pop the cv axles back in and add gear oil to the Differential before you start bolting all the suspension parts back on.

Done!


Special thanks to my old man, the one that had all the good ideas during this project.

[ferraricare]

I am in the middle of this same job, just got the diff out yesterday. Here's my experience: I didn't use the thread rod idea, I just supported the sub-frame on bottle jacks. I also removed the two bolts from the steering rack to sub-frame and moved the rack off the frame allowing for additional clearance and movement. Good Luck!

[PhaseP]

You can get full access down below the engine, which would make the job easier and allow doing oil pan gasket replacement too while you are there, if you do these:

- Disconnect the steering column lower shaft from steering rack input (one pinch bolt under air filter box for N52)
But if you had disconnected the steering rack from subframe this is not needed.

- Disconnect the power steering line loop in front of the radiator that is attached to the front of subframe. I believe connected with one bolt there. It is hanging there for cooling power steering fluid.

- Then disconnect the plastic coolant line that runs infront of the subframe from subframe. It is three small bolts, two close to sway bar bushings, one on the driver side upper side corner of the subframe.

If you have an automatic transmission, there may be some coolant/oil lines coming going back and forth between radiator and transmission. I don't know if these are attached to the subframe or not, I have a manual trans. If they do disconnect these too from subframe.

Now of course engine must be supported from top with engine support bar. At this point you can lower the subframe slowly checking nothing is hanging, by using two jacks, one on the front of the frame, one on the back. As the previous post mentions.

The back of the subframe will have nothing attached to it.

The front of the subframe will only have the steering rack that is only attached to rest of the car via power steering lines which have a good amount of slack, since the steering column lower shaft is disconnected. If you have disconnected the steering rack instead, there will be nothing holding the front subframe to the rest of the car either. If it is the latter you can just remove the whole subframe out of there, making sure the steering rack is supported.
If it is the former, i.e. steering rack still on the front subframe, you can drop the front as much as the power steering lines allow. And then drop the back of the frame swinging to the front as much as you would like. Like opening a door hinged on the front bottom of the car.

I have a XI oil pan gasket replacement DIY post detailing these, since front differential removal is part of the oil pan gasket replacement.

For axle seal removal this tool does the job very good and is cheap:

https://www.walmart.com/ip/Gearwrenc...&wl13=&veh=sem

Using threaded rods remove the need to realign the subframe back up. But you can put it back up using two jacks again, one on front, one on back of the subframe. Lift slow by slow, align, and then thread the bolts slow by slow allowing the bolts to self align the frame under the car. There is an order of tightening these bolts, I think you first torque the front four bolts, criss cross, and then the back two angled ones. Again I had documented these in that DIY post for oil pan replacement, details can be found there.

It is doable on jack stands, that is how I did. Not too easy but it is doable. You do need two jacks for subframe dropping and lifting up, but nothing fancy. Even scissor jacks work. I dropped the frame three times already, once for oil pan gasket, two other times for water pump and thermostat replacement. Thermostat replacement only lasted a year. Water pump is a whole lot easier with the frame down.

[miichau]

Parts list:
Differential (199.00 ebay)

Hey what is the diffs part number ?

[Soravia]

Originally Posted by miichau

Parts list:
Differential (199.00 ebay)

Hey what is the diffs part number ?

Depends on your gear ratio. Search by gear ratio.

[mianko17]

hey I've got the same part to be replaced on my e91 330d drive,

do you have a video or other instruction how to renew the front differential itself?
Thanks

[benh001]

Hi my differential leak at rear side seal to rear drive shaft. Look at picture, is there a way to pop the rear flange, after disconnecting the rear drive shaft from Differential without totally taking drive shaft off?Attachment 2432481

[ramp]

My 2011 e91, 6 speed manual has the same hummmmm on deceleration.
Today the shop quoted me $2500 for differential and oil pan gasket.. I do not have access to lift and it's 15 degrees tonight.

[befunk]

Sorry to resurrect this thread but for some reason I can not find a clear answer for the Torque specs for the 4 bolts that hold the Diff to the Oil pan.


Absolutely fantastic post BTW

[PhaseP]

65 Nm (48 ft lbs)
https://www.e90post.com/forums/showt...3#post19155513