Diff confusion!

[15flounder]

So my e36 has been my trusty daily driver for 8 years. Unfortunately for her, she’s about to be hooned and beat-on as we are going drifting . I was looking at getting a limited slip from Diffsonline but I really shouldn’t afford it since the whole car is barely worth that much. Time to weld up the extisting diff then, right? But I still want to daily it and I can’t be seen skipping and chirping into my parking spot at work. I’d like to keep my open carrier and buy another to weld solid for events. All the carriers I see on eBay say they’re compatible with ratios 3.07 and shorter. Why can’t I find one for my 2.93 final drive? Somebody send me a link. Another slightly more expensive route would be to buy another whole diff and weld it. Maybe in a shorter ratio for more power. Is swapping the whole diff easier than swapping carriers? I haven’t done either yet. Also what diffs will fit my 328is? Any 188mm? E30’s? E46’s? Z3’s? Thanks for reading.

[Team Neverlift]

Any 188mm w/ the E36 diff cover will fit your 328is, using your original Non-M output shafts.

An LSD takes an expensive friction modifier fluid that you do not want to have to replace all the time. You want to leave the axle shafts and diff cover on both diffs, and just swap them out in an hour or so. Swapping carriers, covers, shafts, and fluid every time will be a pain in the wallet and ass.

[wanganstyle]

deleted

[Team Neverlift]

Lsd units do not need friction modifier; it makes the lsd grip less.

The additive is to quiet clutch plates during Whole Foods parking situations nothing else.

Quality diff oil does not wear out all the time; proper oil change interval for diff, engine, transmission oil when doing motorsports events is 1-3 events.

If one thinks diff oil is expensive to change all the time then they need to ride a bicycle with no oils to change all the time.

I do think $70 for 2 quarts is expensive to waste with the OPs original plans for musical carriers. I apologize for any misinformation regarding fluid types, it is what the builder of my 188mm 3 clutch 3.73 recommended I always use.

OT & unnecessary to the discussion, but most bikes these days have hydraulic brakes and dampers fluids that can actually be more costly per mL. lol

[pbonsalb]

Why use $35 per liter diff fluid? Redline 75W90 is $17 and others are similarly priced.

[15flounder]

I was even thinking of saving and reusing the fluid. But swapping the whole diff sounds like a cleaner/easier job but I’d need to have two covers to keep them both sealed. A lot of what I see for sale has the wrong cover or no cover. I’m so wishy-washy on this whole thing. I don’t wanna swap diffs anytime I get the urge to drift. Let’s say I went nuts and bought from Diffsonline. Should I get the most clutches I can afford? Uneven ramp angles means 1.5way, right? Man, I’m still ignorant and I’ve been reading about diffs for days. So many types and so many opinions. I just need somebody to tell me that if I spend almost $3k on a diff, I won’t be disappointed on drift day and I won’t leave marks in the lot at work.

[pbonsalb]

Try rebuilding an lsd diff yourself. Add a clutch or two. See how it works before spending big bucks at diffsonline. Changevthe fluid annually with redline 75W140 or Ltw shockproof.

[15flounder]

Any 188mm w/ the E36 diff cover will fit your 328is, using your original Non-M output shafts.

Does that mean I can get a diff from an e32 or e34 and swap in my cover and output shafts?

[LSxDreamer]

I'd grab an M3 unit using car-part to locate, then follow the first sentence in post #2 if it were me. Those diffs can be found for $200-250.

[M3AN]

Why is there even a debate?

Get two diffs, make each what you want and swap them when you need.

Swapping internals? You're mad.

Buy a bunch of diff seals, you're bound to ruin a few.

[Thrifty S50]

^^^^^

I have a 3.15 welded for shenanigans and a 3.15 LSD for daily/canyon stuff.

Dailying a welded is the worst thing you can do for your ride, and 10x more likely to get pulled over. Ask me how I know lol

[15flounder]

So I tried to locate an inexpensive used LSD with very little luck. Car-part wasn’t much help so I was looking at about $750 shipped from eBay. Rebuild kits to add another clutch or two is another $600. Then, the ring and pinion I want is another $400. At this point, I’d have almost $2k in a diff built by an amateur who didn’t know what he was doing. So I bit the bullet and bought a 3.46 4-clutch LSD with 35/60 ramps from Diffsonline (about $2750 after core return). It’s gobs of money to throw at a 22-year-old car so I’m going to need to have lots of fun at the next drift event. Motorsport is quickly becoming an expensive hobby. I’m still waiting on the diff but I’ll report back for those that are curious.

[15flounder]

Just put the diff in today. Finished up right before it started raining but I went for a test drive anyway. The shorter final drive makes the car seem much more lively and eager. I’m going to have to get used to the way it behaves in turns. Seems like it’s almost reluctant to rotate on entry. Exit is awesome though as I can put more power down sooner. So far, so good. I’ll do another post after the next DE.