Z3 & Differential DIY Day - May 12, 2012

[mcoupemindy]

DATE: May 12, 2012

Who's interested in another DIY day with a focus on differential refreshes?

My new garage and driveway needs to be broken in appropriately.

I will be focusing on differential refreshes, however I have plenty of space for you to tackle other small jobs. I'll be using half of the garage to do differential work, but that should leave a one car bay open and level space outside the garage for four to five other cars.

If you want to come and just hang out, that's fine too - I now have the appropriate space to hold one of these events. Please make sure to write down all your differential questions and I'll try to answer some of them. I'm sure there will be food and beer too! (See Below)

Differentials

I wouldn't mind refreshing SEVERAL differentials. I'll show you how to do the grunt work and I'll help with the detail work. I'm confident that we could assembly line 6-8 in a single day.

Some ground rules (please!):

a.) You must bring the differential OUT of the car. It's a time consuming process to rebuild the differential and we don't want to waste time with installing and uninstalling.

b.) I'll have the parts on hand. There's need to send me funds up front. Please bring cash with you. I need a minimum of one week lead time (prefer more) for seals, etc.

c.) I don't want to get into resetting pinions or changing bearings. If the differential is not whining or making noise, don't mess with a good thing! We can do clutch refreshes / upgrades and seals.

d.) The differential must be a clutch type 188mm LSD. Z3, E30, E36 OK! I prefer to stay on one type for the day. (Others may be OK, however talk to me first.)

This would be a great opportunity to buy that differential that you've always wanted and refresh it before installing in your car, or to refresh that high mileage differential.

Easily accomplished in one day:

2-Clutch Refreshes (stock). Roughly 25% lockup depending on tolerances chosen.
3-Clutch Upgrades. Roughly 40% lockup depending on tolerances chosen. (NOTE: This is as AGGRESSIVE as you'd want to go for a street car.)

Here's an idea of how much this would cost you:

Standard 2-Clutch Refresh: $200

Upgraded 3-Clutch: $300

The big differential builders charge about $1500 (plus shipping both ways) to do this. Do it yourself for about 25% the cost!

NOTE: This is for standard clutch pack LSD's. No love for torsens or opens.

Other DIY Projects

Let you imagination run wild. Just make sure you can accomplish it by 6pm.

Some jobs that can be done: Valve Cover Gasket Replacement, Window Slider Replacement, S54 Valve Shims, etc. Heck, you can just come and wash your car if you'd like. You are more than welcome to use my tools, however they all need to find their way back into the appropriate spots.

Location

The Thayer Complex (my new house) is located very close to the intersection of Rt 50 and Rt 15 at the border of Loudoun County and Prince William County, Virginia. Easily accessible via I-66 (about 9 miles from exit 40), Rt 50, Rt 15 and Rt 29.

Time

I'm an early bird. We can start around 8am, but I ask that everyone is finishing up their projects by 6pm. For the differential refreshes, I'd suggest to arrive by 10am to account for any unexpected delays.

Food / Drinks

I'll have basic cookout foods on hand for the day. It would be appreciated if everyone who ate chipped in a few dollars to offset the cost of food (I'll have a kick-in can next to the grill). I'll also have a couple of coolers with ice - feel free to bring your favorite beverages to share with others.

Parts

I'll be sourcing the necessary parts for the differential builds. You don't need to pay up front, just bring cash with you so we can square up in person.

Sign-up / Registration

Please sign-up here: https://docs.google.com/spreadsheet/...B6ZVE6MQ#gid=0

I need to do this in a systematic way so I know what parts to have on hand and what other jobs to expect. Even if you just want to come and hang out, please sign-up so that I can send you information a few days before.

[KBH22102]

May just come to watch, I spent today swapping the Torsen onto my roadster. BTW, many thanks for your writeup

[mcoupemindy]

May just come to watch, I spent today swapping the Torsen onto my roadster. BTW, many thanks for your writeup

Observation and beer consumption is very permissible!

[lokijibber]

I'm very interested -- unfortunately, I'm not sure if I'm available on the 12th. We're supposedly going away for my parents and our anniversary, and that might be the weekend.

If not, I'm totally in. I definitely want to do this, and I need to replace the output seals too. I'll probably convert to studs at the same time.

I'd want to do 3 clutches. I already have my seal kit.

[z3papa]

I'd love to attend this. Not because I need service since my custom diff is about to be delivered Monday but because I want to see the process.

[Cloudbase]

Dam I just swapped a torsen into my M Coupe. If it was a clutch type I would fly out with it and meet up with you guys.

[Randy Forbes]

I'd love to attend this. Not because I need service since my custom diff is about to be delivered Monday but because I want to see the process.

My sentiments exactly!

[MikeHsu]

I'm down to watch/help! Your awesome for hosting these events

[328 Power 04]

Any chance of a video? Would love to see something like this.

The E36 really needs a refresh (or maybe even an upgrade hmm) and the Z3 is getting a new diff soon.

[xvxax]

Member protomor did a write up if you are not in the Virginia area, check it out.

Some here:
[ame]http://www.youtube.com/watch?v=CM1QE3T6Guc[/ame]

[mcoupemindy]

Good 'ol Yoshi.

[fmcfad01]

Jonathan,
When do you need an answer/payment by?

[mcoupemindy]

Jonathan,
When do you need an answer/payment by?

Late next month. I won't even know market price for the parts until the middle of next month.

[fmcfad01]

K, I like that answer.

[328 Power 04]

Thanks for the video! Actually my main question was if just doing a clutch service to the diff requires to mess with preload, contact, and backlash? It just seems to make the job much more complicated than stacking plates correctly. Even if, I would be up for it, but I don't know what to expect.

[mcoupemindy]

Thanks for the video! Actually my main question was if just doing a clutch service to the diff requires to mess with preload, contact, and backlash? It just seems to make the job much more complicated than stacking plates correctly. Even if, I would be up for it, but I don't know what to expect.

Oh, these aren't standard differentials (like a Ford, etc.). You should check EVERYTHING while you are in it. The tolerances are incredibly tight compared to other differentials. This is why the diff guys charge big bucks. If you are messing with bearings, you have to measure frictional drag in in.oz. YES, that's correct, IN.OZ.!!!

BMW differentials actually loosen up over time as parts wear. When rebuilding, it's important not only to replace the parts but ensure that all parts are within tolerance. This is why I do not suggest to reuse dog ears (friction plates) as they will wear several thousandths over the lifetime and wear unevenly. It's hard to post online, but I have a great example from the last diff I ripped apart as the friction plate wore unevenly across the friction area.

Pinion drag, carrier drag, and tooth pattern are the most important to check.

I'd be more than happy to send you a box with the necessary parts when I bulk order if you want to give it a shot.

[328 Power 04]

Oh, these aren't standard differentials (like a Ford, etc.). You should check EVERYTHING while you are in it. The tolerances are incredibly tight compared to other differentials. This is why the diff guys charge big bucks. If you are messing with bearings, you have to measure frictional drag in in.oz. YES, that's correct, IN.OZ.!!!

BMW differentials actually loosen up over time as parts wear. When rebuilding, it's important not only to replace the parts but ensure that all parts are within tolerance. This is why I do not suggest to reuse dog ears (friction plates) as they will wear several thousandths over the lifetime and wear unevenly. It's hard to post online, but I have a great example from the last diff I ripped apart as the friction plate wore unevenly across the friction area.

Pinion drag, carrier drag, and tooth pattern are the most important to check.

I'd be more than happy to send you a box with the necessary parts when I bulk order if you want to give it a shot.

Lol, OK so there's no easy way out.

I want to rebuild my E36 Diff as well (to 40%, 3 plates), so I may as well get the experience.

[mcoupemindy]

Lol, OK so there's no easy way out.

I want to rebuild my E36 Diff as well (to 40%, 3 plates), so I may as well get the experience.

The good news is, except the ring and pinion, all the guts are almost identical in the 188mm e30 and e36 differentials.

Send me over an email and I'll talk more about it.

[Z3speed4me]

Crap thats like right before the wedding, I will definitely be busy that weekend ensuring everything is all set. I really wanted to come.... Especially since the coupe is going for her surgery the following week. Oh well.....

[mcoupemindy]

Crap thats like right before the wedding, I will definitely be busy that weekend ensuring everything is all set. I really wanted to come.... Especially since the coupe is going for her surgery the following week. Oh well.....

Priorities. Cancel wedding.

[Z3speed4me]

Contemplating.... but my half of the money we make from the reception is helping pay for the motor

[328 Power 04]

The good news is, except the ring and pinion, all the guts are almost identical in the 188mm e30 and e36 differentials.

Send me over an email and I'll talk more about it.

Ok I will email you, thanks for all the info so far. Sometime this summer I may need to borrow the ZF shift pin tools. ... Giving myself way too many projects. Not good.

[Terry F.]

bump for revised title.

[mcoupemindy]

bump for revised title.

Thanks.

I'll post more information, including a signup sheet, later today. The new garage (and house) is coming along nicely and it will be nice to break-in with a gaggle of Z3's.

Also, if you are purchasing a new differential just for this, you can feel free to ship directly to me. The goal is to have both the UPS and FedEx man hate me and my 80# packages.

[fmcfad01]

I might be dropping out of this, but would be up for coming out to give direction and drink beer while giggling at your efforts. Pads, rotors, and suspension on the e39 M5 kinda ate up my car budget. I could be the official scribe/live blogger.