Diff cover upgrade

JHZR2 · 06-01-2010, 03:45 PM

Hi,

Reading about the lack of a drain hole for the diff made me start to think... For older BMW diffs, one can get a highly-finned diff cover from I believe an M-coupe to add extra cooling and possibly extra capacity. And those covers have a drain and fill hole.

What is the commonality for 135i diffs, and is there another BMW diff cover that could work to both enhance cooling (dont know if cooling is an issue with the 135i but anyway), and also to make servicing easy via the presence of an OE drain plug?

Any thoughts?

dcaron9999 · 02-08-2014, 05:20 PM

Quote:

Originally Posted by JHZR2

... Reading about the lack of a drain hole for the diff made me start to think... For older BMW diffs, one can get a highly-finned diff cover from I believe an M-coupe to add extra cooling and possibly extra capacity. And those covers have a drain and fill hole.

What is the commonality for 135i diffs, and is there another BMW diff cover that could work to both enhance cooling (dont know if cooling is an issue with the 135i but anyway), and also to make servicing easy via the presence of an OE drain plug?

Any thoughts?

Reviving an old thread ...

Cant believe no one replied to this. Seems to be a popular upgrade for people which have upgraded to an LSD diff, and are visiting the track...

Are there any options out there besides the $800 one from VAC Motorsports?

Thanks.

Curare86 · 02-08-2014, 05:30 PM

Quote:

Originally Posted by dcaron9999

Reviving an old thread ...

Cant believe no one replied to this. Seems to be a popular upgrade for people which have upgraded to an LSD diff, and are visiting the track...

Are there any options out there besides the $800 one from VAC Motorsports?

Thanks.

I believe there is a finned OEM diff cover thats about 450. However it doesnt have a drain hole. I can vouch for the VAC diff cover. Awesome piece. Dont think theres any viable alternative

dcaron9999 · 02-08-2014, 07:06 PM

Quote:

Originally Posted by Curare86

I believe there is a finned OEM diff cover thats about 450. However it doesnt have a drain hole. I can vouch for the VAC diff cover. Awesome piece. Dont think theres any viable alternative

Do you have an OEM Part #?
Cant find anything on REALOEM under my VIN # ...

Pig Farmer · 02-08-2014, 07:25 PM

Quote:

Originally Posted by dcaron9999

Do you have an OEM Part #?
Cant find anything on REALOEM under my VIN # ...

33117518412

It's not too difficult to drill and tap a drain plug in the cover. For example, if you want to use a drain plug the same size as the OEM fill plug, you need to weld a block of aluminum on the bottom rear of cover. It doesn't need to be super thick... 1/4" is fine. Then drill a 13/16" hole followed up by M22 tap with a 1.5 thread pitch. You could have a decent machine shop do this for under $100.

dcaron9999 · 02-08-2014, 07:36 PM

Quote:

Originally Posted by Pig Farmer

33117518412

That is just the regular stock cover - with no fins...

Quote:

Originally Posted by Pig Farmer

It's not too difficult to drill and tap a drain plug in the cover. For example, if you want to use a drain plug the same size as the OEM fill plug, you need to weld a block of aluminum on the bottom rear of cover. It doesn't need to be super thick... 1/4" is fine. Then drill a 13/16" hole followed up by M22 tap with a 1.5 thread pitch. You could have a decent machine shop do this for under $100.

Thanks. Will consider this for sure.

Curare86 · 02-10-2014, 09:54 PM

Quote:

Originally Posted by dcaron9999

Do you have an OEM Part #?
Cant find anything on REALOEM under my VIN # ...

sorry, Im sure I found it before but I can't track it down now. Harold at HPA made one too... could contact him to see if they have any more?

dcaron9999 · 02-11-2014, 06:24 AM

Quote:

Originally Posted by Curare86

sorry, Im sure I found it before but I can't track it down now. Harold at HPA made one too... could contact him to see if they have any more?

HPA stop selling them, as they were not popular, and only required for clutch type LSD diffs that generate more heat. HPA does not sell clutch type diffs.

Curare86 · 02-11-2014, 08:41 AM

Quote:

Originally Posted by dcaron9999

HPA stop selling them, as they were not popular, and only required for clutch type LSD diffs that generate more heat. HPA does not sell clutch type diffs.

Ah okay, dont know of any other options then sorry. But love my VAC

cheshirecat79 · 02-11-2014, 11:15 AM

The VAC is the only one out there that's finned with a bottom drain hole, unfortunately. Damn expensive.

dcaron9999 · 02-11-2014, 01:22 PM

Quote:

Originally Posted by cheshirecat79

The VAC is the only one out there that's finned with a bottom drain hole, unfortunately. Damn expensive.

... and as I recently found out, is not required for Torsen diffs like the Quaife or Wavetrac, as they dont generate that much heat...

Brian_VACsales · 02-11-2014, 08:20 PM

Quote:

Originally Posted by dcaron9999

... and as I recently found out, is not required for Torsen diffs like the Quaife or Wavetrac, as they dont generate that much heat...

The cover has many more features. Namely 50% more fluid (good for ANY diff unit) fill/drain holes that can be fit for a diff cooler if you ever race, provisions for catch can and temp sensor.

:-)

TT1351 · 02-15-2014, 02:23 PM

Have one on my 1, installed when VAC did my limited slip, awesome piece, go for it, you can't take it with you. My 2 cents. Fran

Dackelone · 02-15-2014, 02:40 PM

Quote:

Originally Posted by dcaron9999

Do you have an OEM Part #?
Cant find anything on REALOEM under my VIN # ...

I believe the OE finned diff cover is for a new 7er or 6er bmw model. It fits bc a friend of mine @elsabor67 bought one from Harold and installed it on his tuned 135i.

Swadeness · 02-15-2014, 03:04 PM

Quote:

Originally Posted by Dackelone

I believe the OE finned diff cover is for a new 7er or 6er bmw model. It fits bc a friend of mine @elsabor67 bought one from Harold and installed it on his tuned 135i.

Hopefully he'll chime in and confirm, maybe with a part #?

Elsabor67 · 02-15-2014, 03:14 PM

I have the cover in question and it comes from a late 90's 7 series. I am not home right now but will be back home tomorrow and will take a picture of mine and with the part ##.

SfValley335i · 02-15-2014, 03:19 PM

looks like these two match up...

e63 645/650 diff

335i diff

Elsabor67 · 02-16-2014, 11:44 AM

Quote:

Originally Posted by SfValley335i

looks like these two match up...

e63 645/650 diff

335i diff

Thanks SFValley, that is the exact one on my car. My bad for the wrong vehicle type. Here is the part number for this.

33117519661

And the link on Realoem
http://www.realoem.com/bmw/showparts...98&hg=33&fg=10

dcaron9999 · 02-16-2014, 11:47 AM

Thanks guys!.

So perfect fit on the back of a 135i large diff housing, and rear mount to subframe is in the exact same location?
Cant see if there is a drain plug on the cover, or just the filll plug ...

As per REALOEM:
On the 650, the Transmission cover is listed as TYP 215K/220K
On my 135i, the Transmission cover is listed as TYP 215L

New21er · 02-16-2014, 02:33 PM

Looks like a fill plug. Maybe have to pull cover off to drain??

Elsabor67 · 02-16-2014, 03:41 PM

I drained mine when I removed the old cover. When I installed the new one I used a Vampire pump to fill up the diff.

PeteA · 02-16-2014, 03:47 PM

Quote:

Originally Posted by Mike@VAC

The cover has many more features. Namely 50% more fluid (good for ANY diff unit) fill/drain holes that can be fit for a diff cooler if you ever race, provisions for catch can and temp sensor.

:-)

Worth every cent.

06-01-2010, 03:45 PM	#1
JHZR2 Major 74 Rep 1,001 Posts Drives: 91 E30, 11 135i cv Join Date: Mar 2009 Location: New Jersey iTrader: (0)	Diff cover upgrade Hi, Reading about the lack of a drain hole for the diff made me start to think... For older BMW diffs, one can get a highly-finned diff cover from I believe an M-coupe to add extra cooling and possibly extra capacity. And those covers have a drain and fill hole. What is the commonality for 135i diffs, and is there another BMW diff cover that could work to both enhance cooling (dont know if cooling is an issue with the 135i but anyway), and also to make servicing easy via the presence of an OE drain plug? Any thoughts?
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02-11-2014, 11:15 AM	#10
cheshirecat79 Captain 32 Rep 919 Posts Drives: 370z & 135i Join Date: Dec 2012 Location: Port Saint Lucie, FL iTrader: (0)	The VAC is the only one out there that's finned with a bottom drain hole, unfortunately. Damn expensive.
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02-15-2014, 02:23 PM	#13
TT1351 Captain 508 Rep 929 Posts Drives: 135, GTS, E30 M3+ Join Date: Dec 2008 Location: Massachusetts iTrader: (2)	Have one on my 1, installed when VAC did my limited slip, awesome piece, go for it, you can't take it with you. My 2 cents. Fran
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02-15-2014, 03:14 PM	#16
Elsabor67 aiming for 450..... 304 Rep 2,910 Posts Drives: Totaled :-( Join Date: Feb 2009 Location: Louisiana iTrader: (28) Garage List 2009 135i [10.00]	I have the cover in question and it comes from a late 90's 7 series. I am not home right now but will be back home tomorrow and will take a picture of mine and with the part ##.
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02-15-2014, 03:19 PM	#17
SfValley335i Colonel 164 Rep 2,409 Posts Drives: Current:135i Sold:335i sedan Join Date: Mar 2007 Location: City of Angels iTrader: (8)	looks like these two match up... e63 645/650 diff 335i diff
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02-16-2014, 11:47 AM	#19
dcaron9999 Major 157 Rep 1,409 Posts Drives: 2011 135i M package Join Date: Jan 2010 Location: Mirabel, Quebec iTrader: (0)	Thanks guys!. So perfect fit on the back of a 135i large diff housing, and rear mount to subframe is in the exact same location? Cant see if there is a drain plug on the cover, or just the filll plug ... As per REALOEM: On the 650, the Transmission cover is listed as TYP 215K/220K On my 135i, the Transmission cover is listed as TYP 215L __________________ 2011 X3 35i with M pack + 2011 135i w/6SPMT \| 255 square tire setup \| Quaife 3.46 LSD \| Diff lock down bracket \| Bilstein B8+Swift SpecR springs+H&R FSB \| CDV delete \| BMS Oil Tstat bypass \| ER FMIC & CP \| N54Tuning DP \| GC Street Camber Plates \| M3 FCA +guide rods+RSFB's+Tranny mounts \| Manzo toe arms \| Cobb Stg2 agressive tune \| Hawk DTC70 brake pads \| RB SS brake pistons \| Goodridge SS brake lines \| Custom brake cooling ducts Last edited by dcaron9999; 02-16-2014 at 11:53 AM..
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02-16-2014, 02:33 PM	#20
New21er Lieutenant 35 Rep 550 Posts Drives: 2011 135i Join Date: Dec 2010 Location: Stanwood, wa. iTrader: (2)	Looks like a fill plug. Maybe have to pull cover off to drain??
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02-16-2014, 03:41 PM	#21
Elsabor67 aiming for 450..... 304 Rep 2,910 Posts Drives: Totaled :-( Join Date: Feb 2009 Location: Louisiana iTrader: (28) Garage List 2009 135i [10.00]	I drained mine when I removed the old cover. When I installed the new one I used a Vampire pump to fill up the diff. __________________ Quote from Ezeedee regarding car mods: "you're only done when you sell the car "
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