All Canadian 240s have VLSD???

[drift-sx]

yeah i was jsut wondering if that is true i have a canadian 240 s13, i just read the http://www.cautioncreativity.com/briand/lsd.htm and it said all them do. Is there a way other then putting my car on a lift to see if i do indeed have one? thanks

[raging panda]

I have talked to quite a few canadians on this issue and they all say that its a lie.

[:: orion ::]

The page linked to above is mine...and that part is a direct cut-and-paste from the old, incorrect 240SX.org page about LSD swaps.

I have read A LOT of conflicting info on the subject...and have no better answer, except it seems that more of them do than do not.

Look for the orange sticker...

Or pull the thing and check out the internals.

Or do some donuts in a figure 8 and see if you lay 2 stripes ALL THE TIME.

Or put one wheel in wet grass on the side of the road and drop the clutch. If you move slowly, you have the VLSD. If you spin and sit there, you have open...

Later - Brian

[drift-sx]

thanks

[jam149]

If you jack up the rear of the car, put it in gear, and turn one tire forward with your hand, the tire on the other side should move forward also.

With an open diff, turning one tire by hand, the other will move in the opposite direction.

joe

[Onizuka]

if you put it in gear it wouldnt move at all, the whole drivetrane would be locked up. (maybe not with viscous cause they have to heat up the silicon to work) correct me if im wrong.

[Dori Dori]

Just pull the passanger rear wheel and look at the diff...there should be an orange sticker (upper right hand side looking into the wheel gap) that says vlsd.

I have a canadian 240 that has a vlsd...it also has hicas and abs (yuk)...but I think all hicas cars came with vlsd, so I'm not a good example.

[jam149]

Quote »if you put it in gear it wouldnt move at all, the whole drivetrane would be locked up. (maybe not with viscous cause they have to heat up the silicon to work) correct me if im wrong.[/quote]

No - if it's jacked up and in gear, the ring and pinion are held, but the spider gears and the side gears will still move freely. It's the spider gears spinning around the ring gear that make one side move the opposite of the other.

However, when testing the diffs, the car should be OUT of gear - not in gear. My bad, and my appologies. (if the car is in gear, EITHER diff will spin the other tire in the opposite direction).

Quote »Just pull the passanger rear wheel and look at the diff...there should be an orange sticker (upper right hand side looking into the wheel gap) that says vlsd.[/quote]

Mine never had a sticker!!! :-(

joe

[Samy]

Isn't it true that only the HICAS equipped models have LSD? I'm Canadian but I think the US 240SX brochure specified that the VLSD came in a optional 'Handling Package' which consisted of a 'Sport suspension' 'Super HICAS' and '205 series High Performance "summer" compound tires' in addition to the VLSD itself. If thats true, then shouldn't checking for the HICAS dash on the light be sufficient, especially if you don't even own it yet (Ie. you're buying a used car)?

[jam149]

Or prolly just checking for the ABS light. I believe the only cars that got the VLSD across all model years were the ones with ABS.

joe

[Samy]

Thats true for S14s. For S13s (According to the US brochures), if you wanted to have ABS you had to have the optional package, not the other way around.

Oh, here's the link for the brochures: http://www.socal240sx.com/faq/specifications.html

[kingsoup]

The word from ottawa 240 group is that 89-90 it was an option and all 91+ have VLSD.

[C-Kwik]

If you jack up the rear of the car, put it in gear, and turn one tire forward with your hand, the tire on the other side should move forward also.

With an open diff, turning one tire by hand, the other will move in the opposite direction.

joe

Wrong. Both VLSD and an open diff will still turn in the opposite directions. The VLSD just has more resistance due to the viscous coupling.

[C-Kwik]

if you put it in gear it wouldnt move at all, the whole drivetrane would be locked up. (maybe not with viscous cause they have to heat up the silicon to work) correct me if im wrong.

The spider gears still allow opposite movements of the two drive wheels. And in order to rule out and frictional properties that would cause forward movement of both wheels, you have to lock the driveshaft into place. Or in otherwords, you are isolating the spider gears as this is where the limited slip action would take place.

[C-Kwik]

Since this topic keeps coming up and always seems to have incorrect info on how to test for a VLSD, I will try to describe the VLSD as best as possible, which will hopefully create abetter understanding of why you need to test it a certain way.

I'd recommend following the link in the FAQ about differntials to find out how a diff works. Particularly the spider gears. This link has a good visual. Make sure to use the straight and turn buttons on the animated portion:

http://auto.howstuffworks.com/differential2.htm

As far as a VLSD, consider first that the internals are essentially the same as an open diff. It has the pinion and ring gear. It has spider gears. Since both have the spider gears, no matter what, if you keep the pinion and ring gear from moving, both output shafts can only turn in opposite directions.

So how does the VLSD work? The VLSD has a viscous coupling that resists turning movement. It attaches to each of the output shafts. All it does is makes it harder for the spider gears to turn. That's as simple as the device is. So with the pinion and ring gears locked in place, turning one wheel will still result in the opposite wheel turning in the opposite direction. But it will be harder to do so because of the viscous coupling.

If you were to have a open diff and a VLSD removed from the car and you took an output shaft in each hand, you'ld find that the open diff shafts will turn in opposite directions very easily. With a VLSD, you can try the same, but you will be struggling to turn it in opposite directions. If it's on the car, with wheels it does become a little bit easier to turn since you can use the wheels for leverage, but the effect is still there.

The problem with leaving the car out of gear is that the gearing would allow the driveshaft to move. If both tires move forward regardless of the type of diff, then the driveshaft will turn. The drivewheels should be turning the same direction when the driveshaft is spun and vice versa. Otherwise everytime you try to move the drivewheels would want to turn in opposite directions. What you want to do is isolate the spider gears. To do this, you need to keep the ring gear from moving. You can hold the ring gear in place by holding the pinion gear in place. And since the pinion gear is attached to the driveshaft and the driveshaft to the transmission, putting it in gear would lock it in place. Of course the motor can certainly turn, but there should be enough resistance to test by just putting the car in a gear. For automatics, putting it in park would do the trick.

When testing, you want to try to feel for the resistance in the spider gears through the wheels. If you have a VLSD, you wil know it. The resistance is not subtle. If in doubt, raise your front end and spin one tire as fast as you can. It should spin somewhat freely and gradually slow down and stop. Then try to do it with the rear. With an open diff, you will have to put a little more effort to get a similar result since it will be spinning the opposite wheel and part of the drivetrain(more weight), but should have similar results where it will gradually slow down. With a VLSD I doubt you will even get it to spin freely. And if you could, it would stop rather quickly.

Testing without the driveshaft locked can confirm if you have an open diff, but can not rule out that you do not have an open diff. If there is enough friction or a slight bind in the spider gears of an open diff, it may turn the driveshaft and if that happens, bith weheels would turn the same direction. So how would you confirm there is a VLSD? This is not going to happen a lot, but how hard is it to put the car in gear to rule out this possibility?

AS a final note, even locking the driveshaft is not perfect science as there is always the possibility that something is wrong with the diff, but short of removing the pumpkin and opening it to visually confirm, this about as close as you can get.

Feel free to respond with any questions. I was a bit long winded so I may not have been as clear as I would like.

[Samy]

I read elsewhere on the forums that in -Canada-, the SE was the base model and LE was the model with options. If this is so, then wouldn't that mean only LE Fastbacks that were equipped with HICAS came with a VLSD in Canada? If anyone has a brochure for Canadian 240SXs between 91 - 93 this would help immensely.

Oh right. The rumor that all Canadian 240SXs have VLSDs is false. (In case ya didn't catch that by now :P