LSD Install

Johnny_M · 02-13-2015, 02:17 PM

I've been searching around the forums for a bit, so I apologize in advance if this question has been answered and the Google has failed me. I received my LSD pumpkin today, and I'm preparing for the installation. I was curious what else are people replacing during the installation of the LSD.

These are the options I've come up with so far:
(12x) Torx Screws (33207572716)
Differential bushings - Powerflex Purple (PFR5-426 / PFR5-425X2) or Black (PFR5-426B / PFR5-425BX2) or leave OEMs in
Lockdown kit or brace - Defiv Lockdown kit or brace from 135droptop
Rear sway bar - M3 22.5mm or 23.6mm - link
Rear sub frame bushings (I've already done this)\
Diff fluid preference?

If you've done any of these, what was your experience with whine/clunk/NVH?

suspenceful · 02-13-2015, 02:42 PM

I'm subscribing to this thread for future reference.

atterbud · 02-14-2015, 11:49 AM

I am wondering the exact same thing. My pumpkin with MFactory LSD arrives on Monday and I have the M3 rear sway bar and new bushings ready to go also. I already have all M3 suspension arms front and rear and he rear subframe mounts replaced. I'm curious if it is worth upgrading the diff bushings. I've found posts in my research that suggest the poly bushings increase NVH and Harold from HPA suggested a few years ago that the M3 bushings were not a worthwhile upgrade from stock. Any other thoughts or opinions?

dcaron9999 · 02-14-2015, 12:00 PM

Quote:

Originally Posted by atterbud

I am wondering the exact same thing. My pumpkin with MFactory LSD arrives on Monday and I have the M3 rear sway bar and new bushings ready to go also. I already have all M3 suspension arms front and rear and he rear subframe mounts replaced. I'm curious if it is worth upgrading the diff bushings. I've found posts in my research that suggest the poly bushings increase NVH and Harold from HPA suggested a few years ago that the M3 bushings were not a worthwhile upgrade from stock. Any other thoughts or opinions?

Went though the same process as you when I installed my Quaife 3.46 final drive large pumpkin installed. The greater stresses and torque from the stock 3.08 to the 3.46 Final Drive had me thinking for a while. Reviews were mixed, and gains were not convincing with the diff bushings. There a three mount points IIRC, and they are as painful to replace as the rear subframe bushings (need a bushing press tool).

I chose not to the diff bushings, and only the rear subframe bushings as a DIY, prior to the LSD actually. When I did the LSD, I bought fresh set of Aluminium output shaft stretch bolts (12 IIRC), and that's I did. No fiddling with Rear+Front Sway Bars at that point, as I was planning for a beefed up spring/damper or coilover setup first...

I like to do my modifications piecemeal to appreciate and enjoy the individual changes they bring to my 135i...

Zombie1 · 02-14-2015, 01:23 PM

Quote:

Originally Posted by atterbud

I am wondering the exact same thing. My pumpkin with MFactory LSD arrives on Monday and I have the M3 rear sway bar and new bushings ready to go also. I already have all M3 suspension arms front and rear and he rear subframe mounts replaced. I'm curious if it is worth upgrading the diff bushings. I've found posts in my research that suggest the poly bushings increase NVH and Harold from HPA suggested a few years ago that the M3 bushings were not a worthwhile upgrade from stock. Any other thoughts or opinions?

NVH isn't bad at all on my car. When I got my Pumkin from M factory I did the Defiv Lock down kit with solid metal bushings. I also have M3 subframe bushings Rear upper and lower M guide rods. I also have full front M3 suspension parts upper lower control arms M3 FSB. My setup is surly stiffer then most would like, but RACKOR. Let us know how you guys like the LSDs.

Pyrat 2 · 02-14-2015, 06:05 PM

I installed the power flex purple bushings along with the M3 rsfb a couple weeks back. I've hardly driven the car since but I did immediately notice a little more vibration coming through from the drivetrain. I'm sure that it's from the diff bushings. I haven't really had a chance to fully flog the car to see how it responds in all conditions. Just making you aware that you will get a little less driveline isolation that you will feel in all conditions.

Dmak · 02-14-2015, 06:44 PM

I m an ex bmw tech at a dealer for 7.5 years. To replace the rear diff you don't need to drop the sub frame. But it's up to u if you want to replace all those sub frame / diff bushings. The axles bolts that you got would need to replace as per the manual. There's also the big 40 mms nuts to connect the drive shaft to diff that should be replace. Personally I would just put some blue locktight and reuse the nut and bolts. Depend if you swapping the complete unit or just the lsd inside the diff. You might need some rtv gasket. Will need diff oil for sure.

02-13-2015, 02:17 PM	#1
Johnny_M Private First Class 9 Rep 101 Posts Drives: Sold 135i 6MT SG Join Date: Oct 2010 Location: Irvine, CA iTrader: (0)	LSD Install - What else should get replaced during I've been searching around the forums for a bit, so I apologize in advance if this question has been answered and the Google has failed me. I received my LSD pumpkin today, and I'm preparing for the installation. I was curious what else are people replacing during the installation of the LSD. These are the options I've come up with so far: (12x) Torx Screws (33207572716) Differential bushings - Powerflex Purple (PFR5-426 / PFR5-425X2) or Black (PFR5-426B / PFR5-425BX2) or leave OEMs in Lockdown kit or brace - Defiv Lockdown kit or brace from 135droptop Rear sway bar - M3 22.5mm or 23.6mm - link Rear sub frame bushings (I've already done this)\ Diff fluid preference? If you've done any of these, what was your experience with whine/clunk/NVH? __________________ // [Sold 08/16] 2009 135i SG 6MT \| Cobb \| Wagner FMIC \| MadDad \| OCC \| RB PCV \| MFactory LSD \| Forgestar F14 \| PSS \| ECS 2pc \| Ferodo \| Goodridge \| M bits \| Koni Sport \| BMW PS, PE, Side Skirts \| Rieger \| Blacklines //
	Appreciate 0 Tweet Quote

02-13-2015, 02:42 PM	#2
suspenceful Major 1110 Rep 1,264 Posts Drives: 2015 M3, 2008 135i, 2009 335i Join Date: Feb 2014 Location: WI iTrader: (9)	I'm subscribing to this thread for future reference. __________________ 750whp 135i Build \| Budget 335i Build \| F80 M3 Build 🎬 YouTube channel (35K+ subs): youtube.com/jakespence135 📷 Follow me on Instagram: instagram.com/jakespence 🏁 Shop BMW merchandise: bimmerstreet.com
	Appreciate 0 Quote

02-14-2015, 11:49 AM	#3
atterbud Private First Class 17 Rep 116 Posts Drives: 2013 BMW 135is Join Date: Apr 2013 Location: Ridgefield, CT iTrader: (4)	I am wondering the exact same thing. My pumpkin with MFactory LSD arrives on Monday and I have the M3 rear sway bar and new bushings ready to go also. I already have all M3 suspension arms front and rear and he rear subframe mounts replaced. I'm curious if it is worth upgrading the diff bushings. I've found posts in my research that suggest the poly bushings increase NVH and Harold from HPA suggested a few years ago that the M3 bushings were not a worthwhile upgrade from stock. Any other thoughts or opinions?
	Appreciate 0 Quote

02-14-2015, 06:05 PM	#6
Pyrat 2 Colonel 1494 Rep 2,564 Posts Drives: Rapidly from A to B Join Date: Jun 2005 Location: Chicago 'burbs or TN Smokies iTrader: (3) Garage List 2024 GT4 RS [0.00] 2022 X2 M35i [0.00] 2007 Z4 M Roadster [8.33]	I installed the power flex purple bushings along with the M3 rsfb a couple weeks back. I've hardly driven the car since but I did immediately notice a little more vibration coming through from the drivetrain. I'm sure that it's from the diff bushings. I haven't really had a chance to fully flog the car to see how it responds in all conditions. Just making you aware that you will get a little less driveline isolation that you will feel in all conditions. __________________ '24 GT4 RS, '22 X2 M35i, '22 GT4, '07 Z4MR '22 GT4 '18 GT3 '16 GT4, '16 M2, '14 X1, '13 135is, '06 330i, '03 323 Ci, '01 330i, '99 M3 (RIP), '96 318is, some non-BMWs
	Appreciate 0 Quote

02-14-2015, 06:44 PM	#7
Dmak Second Lieutenant 75 Rep 252 Posts Drives: 09 135 Join Date: Nov 2014 Location: Edmonton alberta iTrader: (1)	I m an ex bmw tech at a dealer for 7.5 years. To replace the rear diff you don't need to drop the sub frame. But it's up to u if you want to replace all those sub frame / diff bushings. The axles bolts that you got would need to replace as per the manual. There's also the big 40 mms nuts to connect the drive shaft to diff that should be replace. Personally I would just put some blue locktight and reuse the nut and bolts. Depend if you swapping the complete unit or just the lsd inside the diff. You might need some rtv gasket. Will need diff oil for sure.
	Appreciate 0 Quote