Jump to content
Ultimate Subaru Message Board

What's so special about LSD? not the drug


Recommended Posts

Left wheels on ice, right ones on dry asphalt - I assume AWD :D

 

In "Ideal cases":

 

Normal Open Diff:

 

Gas it, and the wheels on ice will spin, those asphalt will stand still. (In actual fact the car will crawl forward.)

 

LSD

 

The wheels on ice will still rotate faster than those on asphalt, but all four will rotate. The "lock-up ratio" determines how big a speed difference left to right.

 

 

Manual Subes have a center LSD, so if both front wheels are on ice, the rears will still rotate and move the car forward. Usually, the diffs are open side-to-side.

Link to comment
Share on other sites

Guest taprackready
Originally posted by the_bard

So what doesn't (or does) my manual 4wd '92 Loyale have? Seein' as I'm not supposed to run it on 4wd on dry pavement, since the rear end will eventually bind up as I go around turns...

 

I know someone on this board is gonna burn me for this but there is nothing in the factory owners manual that says you can or cannot run your subaru on dry pavement in 4x4. I dare anybody to find it in print.

 

Your rear end will not bind up to the point of brreaking anything or stopping the vehicle from forward progress. Your tires will break free before that happens.

 

Flame on

 

Bill

Link to comment
Share on other sites

I agree that you are unlikely to break anything - but in the 1984 owners manual it states:

 

when the car goes around a sharp corner of dry pavement in four-wheel drive while while depressing the accelerator deeply, you may feel as if your car were being braked. In such a case, you should drive the car in front-wheel drive"

 

GD

Link to comment
Share on other sites

Here's your flame Bill.

 

 

IT IS A BAD IDEA TO DRIVE YOUR 4WD SUBARU ON THE DRY PAVEMENT WHILE THE 4WD IS ENGAGED!!

You're not even supposed to run different sized tires on the car.

 

It's bad on tires, axles, and tranny. Binding is a bad thing.

 

 

But I encourage you to go on with your ignorant bliss. Just please don't challenge the board to attack you for giving out bad advice or info. Cuz we will.

Link to comment
Share on other sites

"So what doesn't (or does) my manual 4wd '92 Loyale have?"

 

If you look at the rear of the rear diff on your car there should be a sticker or some kind of marking that says, in english letters, LSD and then some numbers determining the ratio, like 3.7 or 3.9. On my 87 GL-10 I have a green sticker that says LSD, 3.7, Fuji Heavy Industries and then some Japanese writing.

 

Hope this helps.

 

Chad L

87 GL-10 Turbo w/ LSD.

Link to comment
Share on other sites

:D WELD-IT:D WELD-IT:D WELD-IT:D

LSD's are OK, but nothing beats the traction of a welded rear dif. and on the street U can pull 1 rear axle and U will never know it's welded. But when U get off road U will be a trail god, becaus even when U lift a tire U will still have traction. LSD's will give U some traction, even when U lift a tire, but U gota play with the gas and brake to get it and it's not 100% like a spool(welded rear dif.)

Link to comment
Share on other sites

Guest taprackready
Originally posted by Zapar

Here's your flame Bill.

 

 

IT IS A BAD IDEA TO DRIVE YOUR 4WD SUBARU ON THE DRY PAVEMENT WHILE THE 4WD IS ENGAGED!!

You're not even supposed to run different sized tires on the car.

 

It's bad on tires, axles, and tranny. Binding is a bad thing.

 

 

But I encourage you to go on with your ignorant bliss. Just please don't challenge the board to attack you for giving out bad advice or info. Cuz we will.

 

Its not like anybody including me is suggesting to drive on dry pavement in 4x4 for miles and miles. However, People living in snow belts shouldn't freak out if they drive even a few hundred yards between patches of ice and snow on dry pavement without shifing in and out of 4x4. It won't hurt anything. Pulling up a steep driveway in 4-lo because 2-hi wont work isn't going to harm anything. Common sense needs to be your guide.

 

Bill

Link to comment
Share on other sites

It will IF U leave both of the rear axles in all the time. IF U take out one (1) of them when U are driving on the street it will NOT afect tire wear at all. And U can still use 4WD with that rear axle out ( bad road contitions ect.) U will just have 1 tire with power to it in the rear, but it WILL help. ( I know becaus I have done this 3 or 4 time allready);)

U see, the WHOLE 4x4 (trucks, jeeps ect.) comunity has been looking for a way to do this to there rigs for years. Now that rear selectable hubs are ava. for some rigs they can. But the selection is still limited, we can do this to ANY 4x4 Subaru. This is a BIG advantage!! All the traction of a spool, with out ANY of the side efects:banana: I tried to set up somthing like this on by old Bronco II for 2 years, but the money it would have taken!!! I would have been cheeper to get an ARB air locker. But on the Subaru it's FREE!!! all U have to do is weld the rear, and that's eazy.

Brian, Zap, Adam, I know U guys know what a great set up this is, help me out here:-)

Link to comment
Share on other sites

No, they mean welding the gears in the diff so it is "locked". You would have to physically crawl under the car and take the axle out. Unless you are using you vehicle strictly for tough off road purposes, it is uneccasary (sp?) and a waste of time. Look at the hatch patrol for example, they are just running LSD's (for the most part) and they go many places that people could not even imagine a sube going without being dropped out of an airplane (don't laugh, it's been done) Don't waste your time doing it. If you rear says LSD on it, then you are in good shape in that regard. Boz

Link to comment
Share on other sites

Both rear axles on a 4wd have roll pins in them, just like on the front. The exception is that they are pinned on both ends, meaning that if you pull the pins out and elevate the tire you can remove the axle easily. If you practice, it should only take 5/10min to do the job.

I have driven over 250mi with both my axles in(welded diff) on the freeway, but I have a real short wheelbase. It didnt seem to effect anything at all. Call me lazy

:moon:

Rob

Link to comment
Share on other sites

Maroon Doom. Take a look under your car.

 

 

 

Soobme. I am this >l l< close to getting rid of the lsd set up and welding. Off road, the welded diffs rule, hands down. I do a LOT of city driving with my hatch, it's my daily driver. That's all that's slowed me from changing over. That and I'm too lazy to change the axle in and out all the time. I never can tell just when I want 4X, and I usually don't have 10 minutes to get it in. There's a big rockery in my buddy's yard, he lets me park on it when I go there. Would suck to have to install my axle every time I wanna play on it.

Link to comment
Share on other sites

The LSD is just that. It is a clutch pack instead of open side gears that apply traction to both wheels at once. The advantage is that when you loose traction to one tire it will allow some traction to be retained. However, the LSD is/isn't all it's cracked up to be. I have run one for about 3+ years and it's nice but doesn't always give you the traction needed. I installed a welded rear diff prior to the Rubicon trip and it is still in there.

 

Manual Subes have a center LSD, so if both front wheels are on ice, the rears will still rotate and move the car forward. Usually, the diffs are open side-to-side.

 

Not actually, the only factory built Subaru with a center LSD(and front for that matter) is the '04 STi.

 

I too will agree that driving on DRY pavement is not only a bad idea but will indeed bind and eventually break something. Newer generation Subaru's with the AWD system will have viscous couplers that allow this. Old school Subes do not have the viscous coupler to reduce or eliminate low RPM binding.

 

Both rear axles on a 4wd have roll pins in them, just like on the front. The exception is that they are pinned on both ends, meaning that if you pull the pins out and elevate the tire you can remove the axle easily. If you practice, it should only take 5/10min to do the job.

I have driven over 250mi with both my axles in(welded diff) on the freeway, but I have a real short wheelbase. It didnt seem to effect anything at all. Call me lazy

 

Rob, you are lazy!! :-p

Link to comment
Share on other sites

so what does my RX have.. its full time... dual range, with the center lock (saved me a couple times).. hows that work?

the rear lsd is so much fun, its funny when people see me flick the car rally style, and kick it sideways around a corner in the rain with the diff lock on... with difflock off, it dosent like to go sideways too easy..

Link to comment
Share on other sites

Russ's $.02......

Open Axle VS. LSD VS. Welded Diff.....

 

Open axle = Good on the street, good enough in the snow to get you around, no fun for serious off road muddin'

 

LSD = Good on the street, better in the snow, better in the mud. But.. A worn out LSD is no better than an open axle and you never know what you'll find in a wrecking yard.

 

Welded Diff = Not much fun on the street, Scarey as hell in the snow and ice, but Awesome in the mud.

 

If I was going to build a rig for primarily off road use I'd definately weld the diff. For a real world driver, I wouldn't mess with it. I've driven stock subies for 20 years and (as long as I was on a road) they've never let me down. Snow, Ice, Mud, Sand, whatever.

 

It all depends on what you plan to do.......

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...