### Author:  [@julien240](https://forums.speedlife.net/u/julien240)
#### Post date: [July 26, 2011, 6:49pm UTC](https://forums.speedlife.net/t/differential/214950/1 "2011-07-26T18:49:04Z")
I was just wondering how do you find out what differential you have, i have looked on mine for a tag or something but i cant find anything. help me out i have a 1990 240sx coupe
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### Author:  [@frankduxx](https://forums.speedlife.net/u/frankduxx)
#### Post date: [July 26, 2011, 7:36pm UTC](https://forums.speedlife.net/t/differential/214950/2 "2011-07-26T19:36:58Z")
Well there should be a code its something like rs100
find that code and lookit up another way to tell is the drain bolts are in diff spots on the two also the vlsd is thinner than the open hope this helps
[http://www.240sx.org/links/installs/lsd/lsd.htm](http://www.240sx.org/links/installs/lsd/lsd.htm)
---------- Post added at 10:36 PM ---------- Previous post was at 10:28 PM ----------
Sorry wrong link
> **[1991-1994 240sx: Differential fluid change tutorial](http://forums.nicoclub.com/1991-1994-240sx-differential-fluid-change-tutorial-t329296.html)**
>
> \Return to tutorial index\
> \
> oilYou need 2.75 american pints or 1.3 liters.I used 80w-90 gear oil designed for GL4 and GL5 applications. The differential is GL-5. Some people use 75w-90 for cooler climates. My oil was good...
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### Author:  [@\_kris](https://forums.speedlife.net/u/_kris)
#### Post date: [July 26, 2011, 11:30pm UTC](https://forums.speedlife.net/t/differential/214950/3 "2011-07-26T23:30:15Z")
if its a 90 and nobody changed it, i think it came with an open diff… although i could be wrong.
my diff has an orange tag on the drivers side that says VLSD. its a 92…
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### Author:  [@240racer](https://forums.speedlife.net/u/240racer)
#### Post date: [July 27, 2011, 1:03pm UTC](https://forums.speedlife.net/t/differential/214950/4 "2011-07-27T13:03:17Z")
if its the original 90 diff its open. If the cover has a petrusuion on the bottom for more oil its a vlsd. Jack the car up and spin the wheels. If one wheel spins freely its open. if it has some resistence and the other wheel spins its a vlsd… or do a burnout and see what happens. There’s a ton of ways to tell.
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### Author:  [@julien240](https://forums.speedlife.net/u/julien240)
#### Post date: [July 27, 2011, 1:35pm UTC](https://forums.speedlife.net/t/differential/214950/5 "2011-07-27T13:35:20Z")
k thanks ill find out which one i have and if its open i guess im looking for a vlsd
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### Author:  [@derass](https://forums.speedlife.net/u/derass)
#### Post date: [July 27, 2011, 3:20pm UTC](https://forums.speedlife.net/t/differential/214950/6 "2011-07-27T15:20:17Z")
easiest way to tell is to jack up the rear and spin one tire by hand. does ther other side turn the same direction? if yes then its lsd. if the wheels spin opposite directions then it is open.
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### Author:  [@ryan22](https://forums.speedlife.net/u/ryan22)
#### Post date: [August 23, 2011, 7:38pm UTC](https://forums.speedlife.net/t/differential/214950/7 "2011-08-23T19:38:44Z")
I have a 91 which I thought was supposed to have vlsd because it is Canadian, and was babied it’s whole life so I figured it wouldn’t be burnt out, but it only spins one wheel usually
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### Author:  [@Clutchfire](https://forums.speedlife.net/u/Clutchfire)
#### Post date: [August 30, 2011, 12:09pm UTC](https://forums.speedlife.net/t/differential/214950/8 "2011-08-30T12:09:04Z")
i find the spinning the wheel tells you nothing. my diff will spin both wheels the same direction at times and spin one one direction and one the other direction other times. What i do hear is if it had HICAS it should be VLSD. not 100% sure about that though.