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Datassun: destroys its first diff... Send me out a SOS


datASSun

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Ok guys so... Saturday it was raining pretty hard here in Austin and I managed to break my diff. It kept spinning one wheel no matter what and eventually it just snapped. 
 
Now I haven't had a chance to pop the diff cover off to take a look but could someone give me a solid run down of how much is going to be damaged in my R200 ? 
 
The reason I ask and I've searched for this .. is I can't figure out if I should go with the QBX LSD which from what I've read everyone is happy with this application or if I should cough up the 500 bucks a local z car guy wants for a 300zx diff and axles. 
 
Again I've searched and have not found the answer to my questions. 
 
1) Since my diff is already broke what would I have to repair before installing the new LSD. 
 
2) If I install the LSD would I remove the existing spider gears ?
 
3) What will be the quickest way to get my car back on the road. 
 
 
 
 
Now I know this sounds crazy but I daily drive my 76 280z it has a 5.3 liter cam only and T56. Using the JCI mount kit (SUPER EASY) But its the only car I own and need to get back on the road asap. Any local Austin Z car guys are welcome to hit me up as well. Thank you all ! 

 

Pics are attached below. 

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post-39800-0-01258200-1411063230_thumb.jpg

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Absolute QUICKEST way would be to get your hands on a cheap stock r200 and slap it in within a couple of hours. If your local market is like it is here, theyre CHEAP to buy (I wouldnt spend more than about 100 bucks personally)

As far as your other options go- Ill go against the grain a bit and state quite bluntly that I am typically *not* a fan of  the 300zx lsds (assuming that 300zx dif you mentioned is a 300zx clsd). Biggest reason being because of the typical price they go for.  If they were cheap, Id probably reconsider- But for what they are? Theyre usually far too expensive, imo anyways.  I regularly see them go for 6, 7, or even 800 bucks.  And it always baffles me.  For 800 bucks you could have a *brand new* tomei clutch lsd- that swaps in just as easily- And would run circles around those 300zx lsds.  Theyve only got a few clutches in them, even when they were new they didnt have stellar lock up, let alone now that theyre decades old (ie: worn the ef out. inlift city).  You can rebuild them (A member here actually makes new discs/clutches for them- GREAT quality, can not knock them at all!), but when you tack in the price of doing that on TOP of how much you paid for it, again, I cant help but go "...why?" for the previously mentioned reason.  And if youre willing to spend that much on a used, factory, weak lsd (in terms of engagement- not how much power they can hold.  theyre fine in that category), why not buy a used kaaz/cusco/tomei/etc for the same price (or in a lot of cases ive seen, less).  Now if they were like 2-3, maaaybe 400 bucks (For a low mileage one in good condition with good lock up)? Ya, id see the viability in them.  This is actually how much they were when I first got into Z cars- I actually bought a clutch rebuild kit before I had one because i was anticipating getting my hands on one, but they suck up over the years and I said screw it.

I instead went the obx route.  Im a HUGE fan of this diff.  Theyre a bit pricier now, but still cheap- around the 400 dollar mark (I picked mine up new from a guy who bought it and never got around to installing it for only 200 bucks, his loss was my gain :)) I got some ring bolt spacers, bought the upgraded hardware (case bolts/washers, like 20 bucks in hardware), and have been extremely happy with the dif.  Mostly street driving, but from what I can feel it engages quite nicely.  I stacked my washers a bit aggressively for a bit more preload, and have no trouble keeping both wheels spinning.  Donuts, power slides, small drifts, 2 tire peel outs- Its been doing it all for me just fine.  I would go this route again in a heartbeat personally. 

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Well saying you don't like them because they are hard to find cheap is silly :)

 

I got the entire clsd rear end from a car being parted out, plus you can buy new shims and clutch plates, which can be rearranged to provide a lot more clamping force for very little money...

 

Like with all things, just gotta keep your eyes peeled for good deals.

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 It kept spinning one wheel no matter what   Apparently this is the best way to break an open diff.  That's what open diffs do, they spin one wheel no matter what when excess power is appled.

 

Now I haven't had a chance to pop the diff cover off to take a look but could someone give me a solid run down of how much is going to be damaged in my R200 ?  I think that I've read that the bore for one of the spider gear pinion shafts wallows out until the shaft breaks or it just falls out.  So, probably totaled.  I've had the shaft shoot out of the back cover.  Different brand, GM, but same concept.

 

 500 bucks a local z car guy wants for a 300zx diff and axles.  500 for a 300ZX CLSD is cheap.  500 for a 300ZX open is way too much.

 

3) What will be the quickest way to get my car back on the road.  Any long nose R200.

  

Now I know this sounds crazy but I daily drive my 76 280z it has a 5.3 liter cam only and T56.  Seems reasonable, where's the crazy part?

 

Pics are attached below.  I wanted to see pics of the destroyed diff.

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An LSD consists of a whole new carrier, so yes, it replaces the spider gears and their associated weak link. 

 

I've been running the OBX LSD for 2 years now, no issues whatsoever. I can't comment on it for a drag racing application, but given it replaces the achilles heel of the R200, I can't imagine it being a downgrade in strength. I also have a pile of broken thread taps telling me the case material is very hard. 

 

Unless you're equipped to shim the diff, budget closer to $600 for the install. I paid $30 for a hardware upgrade from RBryant (this should be mandatory, and his installation advice along is worth the money) and $150 for a local drivetrain shop to shim the diff and check the wipe pattern. 

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Absolute QUICKEST way would be to get your hands on a cheap stock r200 and slap it in within a couple of hours. If your local market is like it is here, theyre CHEAP to buy (I wouldnt spend more than about 100 bucks personally)

 

As far as your other options go- Ill go against the grain a bit and state quite bluntly that I am typically *not* a fan of  the 300zx lsds (assuming that 300zx dif you mentioned is a 300zx clsd). Biggest reason being because of the typical price they go for.  If they were cheap, Id probably reconsider- But for what they are? Theyre usually far too expensive, imo anyways.  I regularly see them go for 6, 7, or even 800 bucks.  And it always baffles me.  For 800 bucks you could have a *brand new* tomei clutch lsd- that swaps in just as easily- And would run circles around those 300zx lsds.  Theyve only got a few clutches in them, even when they were new they didnt have stellar lock up, let alone now that theyre decades old (ie: worn the ef out. inlift city).  You can rebuild them (A member here actually makes new discs/clutches for them- GREAT quality, can not knock them at all!), but when you tack in the price of doing that on TOP of how much you paid for it, again, I cant help but go "...why?" for the previously mentioned reason.  And if youre willing to spend that much on a used, factory, weak lsd (in terms of engagement- not how much power they can hold.  theyre fine in that category), why not buy a used kaaz/cusco/tomei/etc for the same price (or in a lot of cases ive seen, less).  Now if they were like 2-3, maaaybe 400 bucks (For a low mileage one in good condition with good lock up)? Ya, id see the viability in them.  This is actually how much they were when I first got into Z cars- I actually bought a clutch rebuild kit before I had one because i was anticipating getting my hands on one, but they suck up over the years and I said screw it.

 

I instead went the obx route.  Im a HUGE fan of this diff.  Theyre a bit pricier now, but still cheap- around the 400 dollar mark (I picked mine up new from a guy who bought it and never got around to installing it for only 200 bucks, his loss was my gain :)) I got some ring bolt spacers, bought the upgraded hardware (case bolts/washers, like 20 bucks in hardware), and have been extremely happy with the dif.  Mostly street driving, but from what I can feel it engages quite nicely.  I stacked my washers a bit aggressively for a bit more preload, and have no trouble keeping both wheels spinning.  Donuts, power slides, small drifts, 2 tire peel outs- Its been doing it all for me just fine.  I would go this route again in a heartbeat personally. 

 

I picked up a CLSD in good condition for 400 bucks and a 6 pack. Oh and then after I made friends I came back and used his tools hahaha worth every one of those 400 dollars. 

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Well saying you don't like them because they are hard to find cheap is silly :)

 

I got the entire clsd rear end from a car being parted out, plus you can buy new shims and clutch plates, which can be rearranged to provide a lot more clamping force for very little money...

 

Like with all things, just gotta keep your eyes peeled for good deals.

I didnt say I didnt like em cuz theyre hard to find cheap :P  I said I dont like em when they go for the money they seem to noorrmmaalllyy go for, because on the upper end that they go for you can have a brand new unit that it even better in all regards, or on the lower end, you could buy an "also used" lsd (which probably wont be a couple decades old at this point) that is also better in all regards :) Im not a fan because at those prices, "for the money", theres much better options. When they go for cheap though? Totally into them.  They may not lock as hard, but when youre paying the right price its hard to complain :)  And you can indeed buy new shims/clutches- And you can also indeed orient them to get quite a bit of lock up, but even with this done- theyre still inferior.  Theyve still only got a few clutches inside them.  A kaaz r200 clutch lsd for comparison will have 20 clutch discs. 

 

 

 

I picked up a CLSD in good condition for 400 bucks and a 6 pack. Oh and then after I made friends I came back and used his tools hahaha worth every one of those 400 dollars.

 

I hear you on that.  As long as its in decent condition for 400 bucks? I can promise itll be a lot more fun spinning 2 tires instead of one!  Making new friends is a perk in its own right :)

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