ID an lsd in a 1030 housing

[slow240]

what are the identifying marks for a factory lsd in a 1030 housing for a 240?

im just curious so i might be able to know one when i see it

[PDX240]

I guess I could pull my diff cover and take a look.. Supposedly there is a #'s tag on the back side of the drivers' side axle arm but mine is obscuro.
on the street it's pretty easy to figure out, especially in gravel.
In the jy you can just spin the back wheel on one side and watch what the other side does. IIRC if it rotates in the opposite direction, then no LSD.

[towerymt]

tag
http://www.pbase.com/towerymt/image/109825778.jpg

diff case is split in the middle, doesn't have huge windows like an open diff, has two cross shafts that you can see. once the diff is out, you can look closely and poke the cross shafts and see if they're broken or not. I bought a diff w/broken shafts and could tell just by wiggling them

http://www.pbase.com/towerymt/image/107582307.jpg

that's the 87+ type with socket head cap screws and a tone ring for the speedo. earlier ones had hex head bolts and no tone ring. those 3/8-24 bolts are reverse thread that hold the housing halves together.

[slow240]

are there any external identifiers aside from the tag?
i think the diff in my 242 is lsd but im not sure, it left two black marks on the road and the housing has cooling fins on the bottom, i suppose i could always just take the cover off and change the fluid anyways

[towerymt]

Originally Posted by slow240

are there any external identifiers aside from the tag?
i think the diff in my 242 is lsd but im not sure, it left two black marks on the road and the housing has cooling fins on the bottom, i suppose i could always just take the cover off and change the fluid anyways

1030 had fins and some 1031 had fins. the housing doesn't tell you anything. pull the plug and see if you can peek inside, or pull the cover.

[RCArmy434]

jack up the car, and spin one of the wheels, if they both turn the same direction it has lsd or a locker.

[slow240]

ok, well, i want to change the diff fluid anyways, just because.

so if it DOES have an LSD, what kind of fluid do i use.
if it DOESNT have an LSD, what kind of fluid do i use?

[PDX240]

Cuz I know Towery is a busy guy and also knows his sh1t, I'll re-post our PM conversation from yesterday....

to wit-

Originally Posted by towerymt

I'm not sure if you can determine if the cross shafts are broken or not just by pulling the diff cover and inspecting it. maybe.



I think it's 75w-90 or 80w-90. The other common weight you'll see is 90w-140, not what you want. I always remember it's the thinner of the ones with 90 in the number.



I'd use synthetic, the clutch diffs will generate some heat if you work it hard.



You need to also use some friction modifier like this: http://www.pbase.com/towerymt/image/109825779.jpg



Some diff fluid will say it has that stuff in it. Redline sells fluid with or without it. I'd prefer to buy it separately and add just enough to stop it from chattering. Mine would chatter a lot on slow left turns, so much that it sounded like the exhaust was banging on the body. I had used about 1/4 of the bottle, so maybe an ounce when I initially filled it after we put the diff in. I drained the fluid and refilled, adding most of what I had left from the bottle, so 2+oz and then it was quiet and smooth. You shouldn't need to use the whole bottle. But add it first so you know you won't run out of room once the diff fluid is full.



I can't find good diff cover gaskets so I'm going by what others have said and I'll just use grey RTV from now own. the thin paper gasket sold by the volvo dealer and by FCP is junk and will leak in my experience.



that's about all I know.

[varg]

Originally Posted by PDX240

In the jy you can just spin the back wheel on one side and watch what the other side does. IIRC if it rotates in the opposite direction, then no LSD.

Originally Posted by RCArmy434

jack up the car, and spin one of the wheels, if they both turn the same direction it has lsd or a locker.

You'll miss a lot of lockers if you do that. The right way to do it is to spin a wheel one way than quickly reverse direction, if there is a locker it will engage.