[CP911]

Okay, I might be crazy, but it looks like this is pretty easy to do based on what I've found on newTIS.com right here.

Looks like only special tools needed are BMW Special Tool No. 33 5 120 (found here or here) and a differential support tool for a jack that is apparently not available anywhere (Special Tool No. 33 5 200).

I'm sure I can find a safe way to support the pumpkin even without this special BMW support fixture, and the other tool No. 33 5 120 is still less than what a dealer would charge me to install.

I'm thinking I'd have ultimate peace of mind knowing it was done correctly, and quite honestly, it just sounds fun to take on a project like this on my own car.

Am I nuts? Is this one of those "harder than it seems" type of installations?

[Maynard]

Do you not have warranty coverage? Because I think after you pull and replace your rear diff, you will probably void a lot of warranty on the drivetrain (assuming you aren't ASE certified, or whatever certs BMW requires). Even if no warranty, a benefit of dealer install is that they are going to be there to troubleshoot and fix any unexpected issues. Personally, I'd leave this to the pro's - that 'ultimate peace of mind b/c it was done correctly' seems misplaced on somebody trying it for the first time from online instructions. But hey, it's only the differential - what could possibly go wrong?

[CO_Steve]

I've had the same question. The tool is $500 making any savings pretty small unless you can resell.

[BEM-S4]

Originally Posted by CO_Steve

I've had the same question. The tool is $500 making any savings pretty small unless you can resell.

I haven't done the math or know exactly what you could fuck up but wouldn't this shake out to small $ saved vs big potential repair bill if you screw up?

[CO_Steve]

Originally Posted by BEM-S4

I haven't done the math or know exactly what you could fuck up but wouldn't this shake out to small $ saved vs big potential repair bill if you screw up?

That's never stopped me in the past but I've grown a bit wiser with years.

[3rdcoast228i]

There is an aftermarket tool available for $65 if it's the same one you are talking about.

https://www.hpashop.com/HPA-Differen...4diff-tool.htm

[VPB74]

I just had mine installed. Cost me about $600 and that included the oil. In addition to the tool you pointed out, you also need some special BMW sealant for the nuts, and a second BMW tool to properly remove the axles (you can get way with using a pry bar, but you're taking a chance). I do almost all my own work, but for this job it just didn't seem to make sense from a cost standpoint.

[VPB74]

What year and model 2 Series do you have? I just looked at the link to the instructions that you provided. That appears to be the instructions for older models. The newer M235i and M240i (and maybe others) have a different dual pinion nut setup. This set up requires yet another BMW tool that costs about $600, but maybe the $65 set up 3rdcoast listed would work(?) The tool you list is the one for removing the axles.

[BEM-S4]

Originally Posted by CO_Steve

That's never stopped me in the past but I've grown a bit wiser with years.

Been there too. If the $600 quote is accurate I'd be all over that. Say the tools materials etc cost $200 and I think that's light, maybe saving $400 assuming all goes according to plan?

I always think about it like ok here's a $50,000 car, or you can spend $50,400 to have a warranty. That math gets even better once you start breaking shit during install.

[CP911]

Originally Posted by BEM-S4

I haven't done the math or know exactly what you could fuck up but wouldn't this shake out to small $ saved vs big potential repair bill if you screw up?

That would be correct. I am definitely not considering going down this path to save $. I am merely considering it to avoid having any knucklehead techs touch my car as well as to learn something along the way. This is a 2nd car for me, and with my garage and tool collection coming along nicely, this is more or less just an excuse to enjoy a hobby and educate myself along the way.

I am only slightly worried about potential warranty issues. I don't foresee it being a problem, but you know, Murphy's Law does exist. If I get burned because of some unrelated technicality, well, I will have no choice but to accept responsibility for taking on the risks to begin with. It'll be on me.

At the end of the day, it's a heavy pumpkin held in by a few bolts. Why should it be seen any differently than rotating your own wheels? Both a wheel and a differential are parts in the driveline that affect final gearing and traction. Why is "tampering" or working on one any different than the other?

[CP911]

Originally Posted by VPB74

What year and model 2 Series do you have? I just looked at the link to the instructions that you provided. That appears to be the instructions for older models. The newer M235i and M240i (and maybe others) have a different dual pinion nut setup. This set up requires yet another BMW tool that costs about $600, but maybe the $65 set up 3rdcoast listed would work(?) The tool you list is the one for removing the axles.

It's a 2018 m240i coupe (RWD/manual).

Do you have anything you can point me to where I might be able to see these details?

Thanks for the heads up.

[Poochie]

Originally Posted by CP911

That would be correct. I am definitely not considering going down this path to save $. I am merely considering it to avoid having any knucklehead techs touch my car as well as to learn something along the way. This is a 2nd car for me, and with my garage and tool collection coming along nicely, this is more or less just an excuse to enjoy a hobby and educate myself along the way.

I am only slightly worried about potential warranty issues. I don't foresee it being a problem, but you know, Murphy's Law does exist. If I get burned because of some unrelated technicality, well, I will have no choice but to accept responsibility for taking on the risks to begin with. It'll be on me.

At the end of the day, it's a heavy pumpkin held in by a few bolts. Why should it be seen any differently than rotating your own wheels? Both a wheel and a differential are parts in the driveline that affect final gearing and traction. Why is "tampering" or working on one any different than the other?

You could do it, it's plug and play; if you willing to buy the tool, have a engine stand or jack to hoist the diff, and not weak like me, it's a pretty simple process, as the manual states.

I only had the dealer do it cause i got a deal on the whole package and I didn't have anyone to help me lift it, and of course the expensive axle removal too..

If the motor or diff didn't blow up in a year of usage, it's passed the engineer's threshold of defect and mostly likely you'll never need the warranty anyway.

[petegtsv10]

Originally Posted by CP911

That would be correct. I am definitely not considering going down this path to save $. I am merely considering it to avoid having any knucklehead techs touch my car as well as to learn something along the way. This is a 2nd car for me, and with my garage and tool collection coming along nicely, this is more or less just an excuse to enjoy a hobby and educate myself along the way.

I am only slightly worried about potential warranty issues. I don't foresee it being a problem, but you know, Murphy's Law does exist. If I get burned because of some unrelated technicality, well, I will have no choice but to accept responsibility for taking on the risks to begin with. It'll be on me.

At the end of the day, it's a heavy pumpkin held in by a few bolts. Why should it be seen any differently than rotating your own wheels? Both a wheel and a differential are parts in the driveline that affect final gearing and traction. Why is "tampering" or working on one any different than the other?

I thought the PMs we sent addressed your worries about having a "knucklehead tech" touch your car.....

[CP911]

Originally Posted by petegtsv10

I thought the PMs we sent addressed your worries about having a "knucklehead tech" touch your car.....

Ha! Yes, I gave Ryan a call and left a message this morning. I have not heard anything back yet. Just contemplating an alternative solution in case it doesn't work out going through them. Don't worry - still going to give them a shot pending a conversation with them first to work out the details.

[XutvJet]

I'm a total DIYer and not afraid to do any of my own work. I enjoy working on my cars and have swapped a 350z LSD pumpkin into my old G35 on ramps in my driveway. I researched the price of tools to do this swap on my M235. The cost of tools is around $500 and you might be able to recoup some of the cost. Yes, it is just the matter of removing some bolts, nuts, and prying out the axles. However, the job is not easy on this car. The entire exhaust needs to be dropped from the cat. Suspension control arms need to be disconnected. The axles have to be carefully pryed out with a very special tool or you will most certainly damage the dust seal. Getting the axles in is a bare as well (according to the techs) because the circlips BMW uses on the axles are quite tight and resistant. The driveshaft nut has a very particular torquing method and has a built in seal that needs to be seated within a very short window of time.

After reading the DIY install of the MP LSD, I decided to let my dealer do it. Labor and shop materials was right around $500. Worth it, IMO. No damage to the car either. On a lift and with the right tools, the job is easy, especially if you're a tech and have done similar work. In the driveway, this job would be a bit of a pain for sure.

[CP911]

Originally Posted by XutvJet

I'm a total DIYer and not afraid to do any of my own work. I enjoy working on my cars and have swapped a 350z LSD pumpkin into my old G35 on ramps in my driveway. I researched the price of tools to do this swap on my M235. The cost of tools is around $500 and you might be able to recoup some of the cost. Yes, it is just the matter of removing some bolts, nuts, and prying out the axles. However, the job is not easy on this car. The entire exhaust needs to be dropped from the cat. Suspension control arms need to be disconnected. The axles have to be carefully pryed out with a very special tool or you will most certainly damage the dust seal. Getting the axles in is a bare as well (according to the techs) because the circlips BMW uses on the axles are quite tight and resistant. The driveshaft nut has a very particular torquing method and has a built in seal that needs to be seated within a very short window of time.

After reading the DIY install of the MP LSD, I decided to let my dealer do it. Labor and shop materials was right around $500. Worth it, IMO. No damage to the car either. On a lift and with the right tools, the job is easy, especially if you're a tech and have done similar work. In the driveway, this job would be a bit of a pain for sure.

Really appreciate this post. I have some thinking to do. I really wouldn't mind if I knew 100% that a tech has done this exact job a few times before. It sounds like I need to make some more calls and have some more detailed conversations to make sure that the right individuals would be working on my car before I decide on a particular shop/dealer.

Thanks again!

[Maynard]

I'm shocked it is only $500 in labor - for that it seems a no brainer to let the shop do it. The analogy to changing a wheel is kind of crazy too, given even half the items noted in post #15. And while I understand and respect wanting to learn to DIY, it may be a very expensive lesson. It doesn't seem at all sensible that you are dismissing the factory techs if they haven't done 'this exact job a few times', when you are ready to tack into it as a true first-timer.

[XutvJet]

If this job was like the differential swap on my Infiniti G35, I would have definitely done it myself, even with dropping the exhaust and disconnecting the control arms. Been there, done that a number of times on previous cars. On the Nissan/Infiniti cars and pre-F Series BMWs, the axles bolted onto stubs on the differential. For whatever reason, BMW decided to complicated things with the F series and went with the clip-in/circlip axle setup like you find on a FWD car and those things can suck. Rarely do they ever just pop out and without much leverage, can be hell to pop back in. BMW also installed plastic/rubber dust seals around the axle/diff connection which makes prying a pain.

[XutvJet]

Originally Posted by Maynard

I'm shocked it is only $500 in labor - for that it seems a no brainer to let the shop do it. The analogy to changing a wheel is kind of crazy too, given even half the items noted in post #15. And while I understand and respect wanting to learn to DIY, it may be a very expensive lesson. It doesn't seem at all sensible that you are dismissing the factory techs if they haven't done 'this exact job a few times', when you are ready to tack into it as a true first-timer.

My dealer price matched the best online offer I found for $1,950 for the LSD. It was 3.5 hours to install which is the BMW book time as confirmed by internet searches for what others said labor was at BMW. The tech installing the diff was adamant that he check the fluid level in the diff before install because it had been his experience that some BMW diffs are underfilled from the factory and it’s a pain to check the level and add fluid after the diff is installed. He found the diff slightly underfilled and added about ¾ pint of BMW LSD-spec fluid. All in, it was about $2,700 for the LSD, labor, fluid, and ultra high 10% Kansas tax.

[NISFAN]

What's all this nonsense talk about the diff being a difficult DIY?
I did mine on the drive with a standard jack. I didn't follow the bmw wis, and didn't touch the exhaust. You can dismantle one hub enough to pop the shaft. Then slide the diff sideways off the other side. The popping of the shaft is very easy, a sharp tug and the circlip pings.
My replacement diff had the rubber donut mounted so didn't even have to use any special tools.

[dradernh]

Originally Posted by NISFAN

What's all this nonsense talk about the diff being a difficult DIY?
I did mine on the drive with a standard jack. I didn't follow the bmw wis, and didn't touch the exhaust. You can dismantle one hub enough to pop the shaft. Then slide the diff sideways off the other side. The popping of the shaft is very easy, a sharp tug and the circlip pings.
My replacement diff had the rubber donut mounted so didn't even have to use any special tools.

I hear you, but personally, I don't turn wrenches, having learned over fifty years ago how bad an idea that was, and is, for me. Mind you, I learned this in an auto shop course at school. Imagine how wonderful it was to discover this about oneself at the very beginning of one's life as a car-guy. Not to mention how happy the shops and wrenches to whom I've paid six figures for labor over the intervening decades have been to have me as a client. We're talking win-win here, right.

I wouldn't mind having the skills and confidence of those who choose to DIY; however, I have found that turning the wrenching over to proven professionals, as opposed to dealerships, amateurs, hobbyists, and other assorted pretenders and incompetents, is an effective way for me to get what I need out of my cars. Mind you, I have extensive experience with all of the above.

[VPB74]

I don't think any one said that it couldn't be done DIY, or that it was particularly difficult. It is, however, a job that takes special tools and techniques to do properly so that one doesn't potentially void the warranty on the diff and/or your vehicle. That coupled with the fact that the cost to do it DIY isn't any less that having it done professionally, and it just doesn't seem to make a lot of sense unless you just want the satisfaction of doing it yourself.