[dylim]

Originally Posted by jacobniell

I am not sure but did you all also unbolt all the arms to the wheel hub or did you just remove the subframe with it all connected?

Thanks for the help, I am about to try out this DIY

I did unbolt all the arms, the cv axles etc. Reason is because I was replacing all of them as well - some bushings are going bad. I even removed the cv axles completely as the left outer boot ripped and grease was leaking all over, and I wasn't sure if it's still ok, so I replaced them with new GKN (OE) ones.

The arms were pretty difficult to remove. I didn't have the ball joint separator, only the pickle fork, which always damages the swivel joints. So, if you are not planning to replace them, make sure you get the proper ball joint separators.

I didn't mess with the steering u joint. Since I was replacing all the control arms, I needed turn the wheel left and right multiple times, and I didn't want too many variables, so I just left the steering connected. This results in the steering rack dangling and in the way, but I just used some wires and looped through the mount holes of the steering rack and the engine mounts. This way, I could just push the rack out of the way easily, and there wouldn't be jack stands under the rack.

I didn't bother pressing the brakes for removing/fastening the 4 bolts on the drive axle. I just shoved a pry bar carefully to lock the axle in place.

While the subframe was down I completed a coolant flush and replaced the water pump and tstat. I was planning to replace all the coolant hoses as well, but upon inspection, I think they are all good, so I left them as is.

I also replaced the engine mounts, which were still ok but obviously worn.

Ask if you have any additional questions. Since I just did it, everything is fresh in my mind.

[PhaseP]

Originally Posted by jacobniell

I am not sure but did you all also unbolt all the arms to the wheel hub or did you just remove the subframe with it all connected?

Thanks for the help, I am about to try out this DIY

Since you have an I (RWD) model according to your signature, you don't need to mess with the arms. The DIY described at the initial posts of this DIY thread lowers the subframe, doesn't remove it. It gets lowered enough so that engine oil pan can be taken out.
If you had XI/X-drive, it is somewhat of a different story. There is separate DIY for it at DIY section.

[Efthreeoh]

Originally Posted by crowtrobot

Thanks for this excellent DIY, could not have done the oil pan swap on my 128i without it.

Everything went really well until I put the pan back in and replaced the oil level sensor - one of the studs holding the sensor snapped! The steel pans for the manual are impossible to find second-hand, and pretty expensive new, so I ended up buying a second-hand aluminum pan from an auto. A few modifications were necessary to get it to fit, I detailed them in a thread on the 1er boards: https://www.1addicts.com/forums/show...0#post25028120

Everything's back together, and no leaks so far! Also took the time to add an OE oil-water cooler, replace the waterpump/tstat, and replace the engine mounts. Nice to have the extra room while the subframe was down.

Thanks for posting the link to your aluminum pan swap. My steel oil pan has finally begun to leak around the oil level sensor and having removed it once, I'm concerned the rusted studs will break if I try to clean up the surface rust on the pan at this point. I'm pretty sure I'm going to convert to the aluminum oil pan. Being an '06, my N52 has the oil return line, so I'll need to get the additional parts for the '06 N52 automatic oil return line.

[DEWZE90]

Wanted to say thanks to everyone who has completed this and offered their solutions to each model's unique differences, and a special thank you to the OP for starting this. I used this thread entirely to complete this over the past two days in my garage. In all it took me roughly 20 hours, but that included new transmission mounts as well. I also replaced the motor mounts too as my 330i has 138k on original mounts. I wanted to give some advice on a 2006 330i Automatic.

First issue was like everyone who has a 2006 indicated, the oil return hose will likely give you fits. I tried multiple ac/fuel line dis-connectors without any success. I finally decided to try the screwdriver and hammer, which with one whack broke a tab off of the connector, but one more whack had it off. Luckily it snapped back on and appears very tight so I left it.

The real issue I had was getting to most of the driver's side pan bolts, due to the Automatic having two hard cooling lines running right along the pan where the bolts are. Those are tough to get to on their own, but dealing with hard lines right in the way made it that much worse. I finally ended up using zip ties to try and pull them as far away from the pan as I could.

Another very tricky bolt to get to was one of the three bolts on the backside of the bellhousing, running into the oil pan. One of them is in a very bad spot with no room to get a ratchet on them. Luckily I had a very small E12 ratcheting wrench which did the trick (used during a prior OFHG replacement).

The pan removed easily from the rear (once I figured it out that it was the only way it would come out). I had no bolts or parts in the bottom of my oil pan, and considering mine is an early production 2006 I felt lucky based on the posts here. I then did the zip tie trick to keep the gasket in place when re-installing from the rear, that worked out really well!

Next time zapper was trying to get my Snapon Techangle Digital Torque Wrench on those driver side pan bolts, I think I used every extension in my arsenal. I truly don't know how you would verify proper torque of 8nm and 90 degrees without one of these fancy torque wrenches.

Anyway, once I got the pan bolted up and torqued in proper sequence (starting in the middle and criss crossing) everything went back together like clockwork.

Cheers!

[Astrodubzy]

Originally Posted by Meeni

Excellent DIY, it has everything.

While there, you may consider changing the engine mounts, at the time the pan starts leaking, they are probably also getting fairly used.

Just wondering other things other than oil level sensor, and engine mounts I could replace while in process? Did I see tranny mount too? I was thinking of replacing At pan with aluminum one. Bc i guess oem tranny pan does not have removable filter and it's better than plastic. But my mech did say something about a front diff seal is that necessary aswell. Help please!! Just want to so it once and the right way yk!
2011 335xi n55€

[csquared013]

Originally Posted by Astrodubzy

Just wondering other things other than oil level sensor, and engine mounts I could replace while in process? Did I see tranny mount too? I was thinking of replacing At pan with aluminum one. Bc i guess oem tranny pan does not have removable filter and it's better than plastic. But my mech did say something about a front diff seal is that necessary aswell. Help please!! Just want to so it once and the right way yk!
2011 335xi n55€

I just got a quote for the job to see if it was worth the headache to do it myself and on the quote the mechanic had the diff seal listed as a replacement without me even asking so I'd say go for it. I'll be doing my diff seal when I break into everything this fall.

[karmatose]

Great write up. I just did this job on my car. Couple of take-aways from it:

First, since I live in the rust belt, every single one of those cage nuts on the cross brace/lift point broke and left the bolt spinning. I did end up dropping the whole subframe because of this and I figured I would be unable to complete the job with it in the way based on things I've read in this thread. I also read of people in this thread getting a wrench up there and I also tried to get a prybar in there to brace it but failed. My ultimate remedy for this was to heat the ever-loving hell out of the bolts that go through the cage nuts, wedge a pickle fork in between the brace and crossmember and zip them out with an impact. Worked great. I wish I had thought of the pickle fork idea before the subframe was out of the car.

Second, since I have a 2006, I also had to deal with the oil return line to the pan. It was extremely fragile and touching it caused it to break immediately so this was probably for the best as I got the oil pan out easy but left a broken hose there. Since I didn't want to go down the road of removing my intake manifold (as this job had already spiraled out of control what with removing the subframe), I managed to change that hose from the bottom by removing the shield over the fuel lines near the ground strap. It is completely blind but doable from below. Removing the cowl also made it easier to see what was going on down below because it gave you some light. The hardest part was removing the electrical connector as the clasp is facing inwards towards the block. Just slip a pocket screw driver in there and push the latch towards the block gently and pull the connector. As far as replacing that hose, a little silicone spray helped seat the o-rings on the new tube for reinstallation.

Third, after completing this job with the subframe completely out of the way, I think just removing it is the way to go. Getting the oil pan in and out was not pleasant as it was but having to work around that aluminum monstrosity would have just frustrated me to no end. Yes, it adds a few hours to the job but I was surprised how quickly it did come down and getting it back in and lined up was pretty straight forward.

Fourth, there's no better time to replace your water pump than when you're doing this job. I should have done that but it was not in the budget.

At any rate, thanks for the write up, OP. It was handy even though I deviated from it quite a lot.

[feuer]

Originally Posted by Plasmid_Boy

Yes, I read your DIY, it is of great help and thank you for that. I did clear the front tube as you suggested, but the hang-up was at the rear in the transmission. I have an automatic. I have attached couple of pictures showing where it got hung up and the plastic cap.

What are you talking about? That’s false. Plastic cap is to access torque converter bolts. Will all bolts from oil pan removed it will drop freely, AT or MT regardless as they share the oil pan. Often people miss the two bolts that go through the bell housing.

[ryan stewart]

I get to join the club. Thanks for this thread because each youtube video has a different technique and obviously different demands based on the VERY specific configurations everyone had. I was able to find the "what the shit, mine doesnt look like that" resolutions in here.

2008 E91 328i auto N52k.

I started it yesterday afternoon and just got to "seeing the light" phase over lunch today, should get the pan off and back on today.

Turns out though I wont be in any rush though, I was stupid and let one of my arm hairs brush up against the top radiator hose and the nipple for the overflow hose shot off with the violence of an NBA player faking a foul, so I went ahead and pulled the rad fan and will be doing ALL of those hoses on the front of the car, I didn't do them when I did the water pump (4 way, hoses in and out of the tranny cooler, to the engine head, rad).

Ill try and take some pics to add to the pile since I have a climate controlled garage, a lot of lighting and (now) plenty of time.

I did basically drop the entirety of the subframe to where it hangs on the steering rack, and just have the rack lowered. Honestly if you can really get the car up and havent replaced the bottle/filter you might as well drop it too. but either way plenty of space now.

I am dreading what Im going to find in the bell housing though. That pile of oil came out of the rear bolt holes overnight AFTER an overnight oil drain.

If anyone wants a specific pic while I have it torn down LMK:







I did go ahead and get new bolts for the engine mount arms since I saw some references that those can shear, already replacing my mounts as the passenger side one collapsed (it was riding on the bump stop).


And after draining the oil this is what came out overnight from pulling those rear bolts, so guessing that is where my quarter-quart-per-change was going (I wasnt getting drips, just gunk on the pan):


Hopefully there is no issue with that amount of oil getting in back there, I know manuals have issues with clutches and flywheels but hoping this doesnt create a problem with the torque converter.

[ryan stewart]

LOL, so here are my oil pan treasures. Looks like slivers of plastic off of a guide of some sort. The lower chain guides look great so guessing up on the head somewhere, but just edges so no concern.

The wildcard is, a hose clamp? Didnt see any signs of hoses in the bottom. I dont recall seeing any in the head either, someone drop something when the VC was off? The hose clamp is of the Click-R style but doesnt appear to have ever been crimped:

[mantis]

ugh im not looking forward to this chore, 2011 328i 170k automatic. i see oil coming from my lol filter housing too now.

oil pan gasket
engine mounts
trans mounts
m3 control arm kit
sway bar and end links
tie rods
and now thinking about sub frame bushings since its dropped

am i missing anything lol

[ryan stewart]

No sub frame bushings on the front, just 6 big ass bolts.

Once Im done Ill come back and add some notes about the oil cooler pipes and whatnot. Someone mentioned them but I took some pics for documentation to help. Pulling those helps a TON because it clears a lot of space on that drivers side to reach the bolts.

[mantis]

Originally Posted by ryan stewart

No sub frame bushings on the front, just 6 big ass bolts.

Once Im done Ill come back and add some notes about the oil cooler pipes and whatnot. Someone mentioned them but I took some pics for documentation to help. Pulling those helps a TON because it clears a lot of space on that drivers side to reach the bolts.

i cant remember if i had insurance replace these sub frame bushings on last accident or not, i will be of course looking over all parts and upgrading what i can while the cars down

[ryan stewart]

No I mean there is no such thing as a subframe bushing on the front subframe on our cars, it directly mounts to the frame rails via 3 big ass bolts on each side.

The only other things I would consider are cooling parts and maybe O2 sensors. Cooling parts because that electric water pump can become a ticking time bomb after 100k and those plastic coolant fittings can be brittle as hell after a few years. Im DONE with everything but now waiting on a replacement coolant hose set because I cracked one by bumping it. Im doing everything on the front because I already did the ones around the pump/stat when I replaced them.

[ryan stewart]

Ok so here are the pictures regarding the transmission cooler/heat exchanger lines for the late model automatics (not sure if this is on early autos, only heard people refer to it in the 328)

If you see in the first pic on the right there is that plated big metal lump. That is bolted to the rad fan shroud. Just unbolt it and you can leave the fan in if youre not doing coolant hoses, etc. It will just hang freely supported by both its lines and the coolant hoses. Since i was leaving the car for a few nights and didnt want the extra stress on the plastic rad fittings I did support it with a bungee:



Tracing back there is the first clip, just LOOOSEN the nut until its on the end threads, it just clamps to a slot cast in the oil pan so that's all it takes to get free.



Then on the rear 3rd of the oil pan is another, same thing just loosen:


Then remove the panel covering the tranny and you can see how its clamped on pretty simply, one 13mm. WHen you pull the hoses out make sure and retain the little O-rings, dont want them falling and getting kicked away.



When you pull it out its going to drop the tranny fluid that is in that heat exchanger so be ready with something to catch it. Tilt the lines down to get as much out initially to save yourself the trouble as you jostle it later.

Once you have those 4 contact points free those hard lines can move A LOT with no effort, as you can see Ive pulled them over a foot away from the back of the pan here, just resting on the dropped subframe.



Frees up a TON of space on the drivers side to get to those bolts, I dont think I could have properly torqued them down without dropping them.

Reinstalling is just reversal, and you probably lost about 600ml of fluid so DONT FORGET TO DO THE TOP OFF PROCEDURE for the transmission (fill to overlfow with level car, run to temp, shift through gears, top off until overflow, button it up).

Also, while these lines are fairly robust plastic exercise care. Just out of curiosity I looked them up and they are $100 and not commonly stocked.

[mainbearing]

Found some newer DIY videos. They showed unbolting of extra stuff like the ATF cooler, radiator fan, 3 brackets for the ATF cooler lines and the air filter box. These may be more specific to the aluminum pan than the steel pan.

The first video has many details that other videos lacked. There was a segment in it on the lengths of oil pan bolts for the 2008 w/ 6L45. That digital torque wrench is nice! The job must have been be a breeze, as he was wearing flip flops, LOL!

I spent some time before starting the job on these two:

Video on a 2007 328xi:

My original references among a couple of others. A summary-only of (E90 N54) oil pan gasket change and a DIY subframe drop:

[eljay]

I am in the middle of a front suspension refresh...now that I see this, it sounds like removing all control arms, links and tie rod ends is about a third of the battle, right? So, I wonder if I should do this now.

[mainbearing]

You can keep all those connected while you drop the subframe and change the OPG as in this DIY thread, then do the suspension refresh.

I changed the struts after the OPG, but should have bought the rest of the parts as my passenger side tension strut bushing is seeping (probably the same pothole that caused the light oil leak on the right strut).

Originally Posted by eljay

I am in the middle of a front suspension refresh...now that I see this, it sounds like removing all control arms, links and tie rod ends is about a third of the battle, right? So, I wonder if I should do this now.

[mainbearing]

Well it was my turn changing out the poorly designed oil pan gasket, leaking at the rear passenger corner of the aluminum pan and also into the bell housing. Obnoxious oil fumes and maybe blowby gas were seeping into the cabin, even in recirc mode.

It took me about 3 hours from jacking the car up on all fours, drained oil, loosened pipes and harness, to the point of removing 18 of the 28 vertical pan bolts, followed by the 6 bolts dropping the subframe. Then the 10 driver side pan bolts took me another hour because of access. 3 of those bolts can be access through the subframe if the driver-side mount is removed (old mounts were compressed but not leaking, but out they go.) The other 7 bolts I either just reach up in there or use a combination of long extensions, wobble and u-joint. If the air filter box is removed, 4-5 bolts are also easily accessible from the top side.

Initially I only loosened the air filter box (two 10 mm) to get better access to the front ATF cooler line bracket (three, 10 mm/13 mm) and the driver side bolt for the coolant pipe (total three T30). I also removed the T25 (can't they just use fewer sizes?) for the Modine ATF cooler, which may not be necessary.

The ATF cooler lines at the transmission blocked one horizontal and one vertical pan bolts on the driver rear corner. Loosen the brackets and swing it out of the way (13 mm removed at the transmission, two 10 mm nuts just loosen).

Like some others with the aluminum pan, I ran into the same problem with all bolts out, the pan was jiggling but simply would not drop! Yes I know the round protrusions and that some did not have problems. But it took me an hour fighting it whichever way then decided just to come in and surf the web. Went through the videos again, no dice.

NO, it was NOT the crankshaft pulley counterweight, part of the serpentine belt, the oil level sensor, or the AC line in the front. Wasted like 3 hours messing with it and searching the web.

It turned out the sheet metal sandwiched between the engine and transmission had a little flex and was catching the passenger-side round protrusion. While prying the pan forward a little, I used a long screwdriver to push the sheet metal away from the protrusion and the pan dropped. Try prying the pan loose from the front of the engine, and not like I did at the passenger-rear side pry point (that may be what contributed to the protrusion catching).

Jacking up the front subframe bar a little will drop the rear and allow more room for the pan to slide out.

Then it was just cleaning the pan and gasket surfaces. I first applied a light coat of Permatex Ultra Black on the pan, drop the gasket on there, then another coat on the gasket. The gasket stayed on there fine, therefore I did not need zip ties. I was sure some smeared along the way putting it back, the protrusions meant you had to lift and slide the pan a little rearward and not straight up like other engines I have done. I was not relying on the cheap-looking rubber to do the sealing. RTV was my primary seal and I hope this did the job.

A new Ajusa (Ajusa 16078850) oil level sensor gasket was used.



New CRP pan bolts (CRP HWK0003) already had threadlocker applied. It was a little harder to start than non-coated ones, but once in they turned fine. I decided just to use my calibrated elbow on these after reading what Efthreeoh did.

Both engine mounts (Corteco) and passenger side mount bracket bolts (CRP HWK0033) were replaced. I should have replaced the driver side bracket bolts too, but only had one kit on hand.



Another thing I wished replaced was the oil pickup tube o-ring and the 3 aluminum bolts. I decided not to smear RTV around where the tube enters the oil pump. If that o-ring is as bad as other gaskets on this engine, I would replace it while the pan is off.

I would say the pan gasket in whole took about 12 hours (not counting about 3 hours additional for the front struts), but I see 6-8 being a possibility for the gasket alone knowing what I now know.

The short pan bolts (M8x26mm) are on three sides: 9 on the driver side, 4 on the front, and 10 on the passenger side.

The 5 bolts on the bell housing side (looking from the rear to front) from the driver side to the passenger side they are: 2 92 mm, 2 112 mm, and another 92 mm. The left-most bolt is blocked by the ATF cooler lines.

Therefore if you bought the CRP HWK0003 kit, there will be 112 mm ones left over with the GM 6L45.



Two horizontal bolts (center and right) would come off with the harness bracket. And the third, left-most one is higher up on the driver side, again blocked by the ATF cooler lines.



This is about how much I squeezed out of the tube:


Also, in removing the 6 subframe bolts, I would recommend removing rear mounting bolts first (the ones going 45 slanted into the chassis), then the middle one and finally the fronts while the subframe was supported.

There have been two member posts about thread damage for those bolts (https://www.e90post.com/forums/showthread.php?t=1858639). I suspect removing of the bolts while the subframe's weight on them might be the reason (even when supported as mine was). But easily resolved with a Harbor Freight $19.99 tap and die set (https://www.harborfreight.com/carbon...-pc-62832.html). The first turn of the thread was slightly buggered that a milder "thread chaser" would not thread either. I believe it was the M12-1.5.

Installation iirc Bentley says to install the fronts first. Therefore reverse the order.

Many thanks to KrashFinatik for starting this DIY and all those members who contributed since!

[shimstack]

Thanks everyone for your contribution to this DIY. I took this on over the weekend and it was going great until I broke one of the oil pan screws on installation.

As some have said, the torque wrench is virtually worthless for this as the thread locking compound on the new screws creates so much drag that it takes more than 8N-m of torque just to thread the screws in loosely. On 27 of 28 screws, the tactic of snug + 60° worked great. On one, I didn't think it was actually snug, but it was, and snapped before I got 60° on it.

I tried a left had drill bit and I tried an easy out, but neither worked to extract the broken stub. I ended up drilling and tapping the remains (M8 X 1.25 thread) and re-using one of the old screws with fresh loctite. It worked. It's probably not quite as tight as the others as I was a little gun shy with the old screw, but it's holding.

Overall this wasn't as difficult (apart from the mishap) as I expected. I have the easiest configuration N52 car: 6MT, RWD, and 2008, so no oil return line. If you're contemplating this job and have the same specs- go for it. I thought I was on track to finish in 5 hours (on jackstands, with hand tools and an electric impact gun) but it ended up eating a little more time fixing my fXXXup.

Also, draining the oil overnight surely reduced the mess. I had to do this job on my Toyota Tundra to fit a turbo oil return to the pan and it was a horrific mess. The BMW was far cleaner.

Thanks again.

[Samurai_Shadows]

So, I have my engine on the stand and I am about to start replacing majority of gaskets that I wouldn't want to do while the motor is in the car. I ordered the new gasket and new bolts. After reading majority of this thread, is there anything I can put on the new bolts to prevent any additional unwanted resistance while torqueing them ?

[POBEP]

I read the entire thread and want to say thank you all.

Mine OPG is leaking beyond my comfort level now.
For this project I will pass on DIY as:
1) my home mechanic execution time will considerably exceed my professional hourly rate when compared to paying 8-10h of trusted professional car shop labor + lost drop off and pickup trips time
2) there will be additional time spent cleaning oily mess everywhere

My 2009 E91 (N52KP) has been garaged in San Francisco its entire life (13y/104,000mi)
There is no signs of rust anywhere.

I know this question was asked before, however will ask it again in 2022:

Should I have my mechanic replace:
- plastic oil return line
- oil level sensor seal
- engine mounts (there is no vibration of any kind)
- WP/thermostat (running on factory ones, no fan spinning or WP codes)
- anything else?