viscous coupling in center diff

D

Dave_Frumkin

Can the VC in the center diff be removbed and make the car 2wd.? I
live in TX now not much in the way of snow.
 
Dave_Frumkin said:
Can the VC in the center diff be removbed and make the car 2wd.? I
live in TX now not much in the way of snow.

If you could, it would be a minimum of four hours, to drop the transmission
and pull the transfer case off.

BTW, you wouldn't have a 2wd car, but an AWD car with an open center
differential. Normally power would be applied to all four wheels, however
if one wheel spins free, no torque is transmitted to the other axle anymore.

Don't you have mud and wet grass in TX?
 
Don't you have mud and wet grass in TX?

Or wet roads or bumpy roads or normal roads? AWD is superior in all ways
regardless of conditions!!

Why would you Buy a Subaru with a main selling feature of AWD then try to
turn it off, buy a Kia or something.

Admittedly fuel economy suffers but the advantages are worth it...
especially on those country B roads ;o) with that flat four screaming at
7000rpm and those Brembos biting off huge chunks of speed as you blip the
throttle on the down change setting yourself up for the perfect balance
round the next corner before unleashing over 250bhp of mechanical
harmony.... Bliss!!!

Maybe AWD isnt the only selling point for Subaru ;o)

R
 
Or wet roads or bumpy roads or normal roads? AWD is superior in all ways
regardless of conditions!!

Why would you Buy a Subaru with a main selling feature of AWD then try to
turn it off, buy a Kia or something.

Admittedly fuel economy suffers but the advantages are worth it...
especially on those country B roads ;o) with that flat four screaming at
7000rpm and those Brembos biting off huge chunks of speed as you blip the
throttle on the down change setting yourself up for the perfect balance
round the next corner before unleashing over 250bhp of mechanical
harmony.... Bliss!!!

Maybe AWD isnt the only selling point for Subaru ;o)

R
I notice the AWD kicking in all the time. Especially if I'm making a
sharp turn from a stop. I can hear a wheel or two slip a little then
the traction control takes over and things never get out of control.
I also notice the AWD when it rains really hard. And I really notice
it when running through the mountain twisties.
I wouldn't think you would not gain that much mileage by only running
to two wheels. And you would loose all the advantage of AWD.

BlueSTi
"Scary-Fast"
 
Just pull the damn rear drive shaft and get machined plugs for the rear end
of the transmission and for the front end of the rear differential so oil is
retained.
 
Just put the FWD fuse in.


Someone can correct me if I'm wrong, but I'm pretty sure that only works
with the H4 auto. You can't just put the fuse in with manual transmission
cars or cars with VDC.
 
@posting.google.com>, (e-mail address removed)
says...
Can the VC in the center diff be removbed and make the car 2wd.? I
live in TX now not much in the way of snow.

Better off saving money by selling the car to
someone that values AWD, and getting something
cheap-er. Some of the cost of the Subarus,
relative to their class, is the AWD.

Kia, and Hyundai, produce comparably sized
vehicles for much less, that should produce much
better MPG.

Or, you could spring for an SRT-4, after all,
they are teh fastAr.
 
Someone can correct me if I'm wrong, but I'm pretty sure that only works
with the H4 auto. You can't just put the fuse in with manual transmission
cars or cars with VDC.

Correct!

Barry
 
Ross said:
Why would you Buy a Subaru with a main selling feature of AWD then
try to turn it off, buy a Kia or something.

See Dave_Frumkin's other thread where he describes how his VCD unit is
busted causing binding during low-speed turns.
 
How about taking the rear half shafts out?
Someone can correct me if I'm wrong, but I'm pretty sure that only works
with the H4 auto. You can't just put the fuse in with manual transmission
cars or cars with VDC.
 
See Dave_Frumkin's other thread where he describes how his VCD unit is
busted causing binding during low-speed turns.

Replace the Diff, Im sure the cost difference would not be much as opposed
to disabling the rear drive and the car would be running as designed, would
have higher resale value, no insurance implications and be less likely to
fail as a result of untested stresses etc. The car would arguably be more
dangerous as the suspension and weight distribution is set up for AWD not
2WD. The 2wd fuse is there for towing the AT box Subarus not for driving
them.

If you are spending all that labour time in about the drivetrain why not
just replace the diff at a few extra notes and be rest assured that the
mechanics are carrying out a normal routine job not a custom botch that they
will never have had any experience doing.

R
 
From: "Ross"
The 2wd fuse is there for towing the AT box Subarus not for driving
them.

How so? If you put a fuse in to enable fwd only, then the car would have to be
running in order for it to take effect. I believe that feature is present to
allow driving with a mimi-spare, or in case of problems with the center/rear
diff. It would allow the car to be driven short distances for repair.

It is NOT there to permantly convert the car to fwd, but the "only for towing"
thingy has become something of an urban legend.




George Adams

"All good fishermen stay young until they die, for fishing is the only dream of
youth that doth not grow stale with age."
---- J.W Muller
 
How so? If you put a fuse in to enable fwd only, then the car would have
to be
running in order for it to take effect. I believe that feature is present
to
allow driving with a mimi-spare, or in case of problems with the
center/rear
diff. It would allow the car to be driven short distances for repair.

It is NOT there to permantly convert the car to fwd, but the "only for
towing"
thingy has become something of an urban legend.

I stand Corrected, I knew it was something to do with not driving 2WD
permanantly. The space saver wheel is smaller than the others and the 2WD
mode is to take the LSD's offline and leave the fron OPEN diff running.

Running a smaller wheel with the AWD would damage the center diff and the
rear LSD due to the constant difference in rotation speed of the wheels.

Now that i think about it it makes sense.

;o)

R
 
george wrote: (clip) It is NOT there to permantly convert the car to
fwd, but the "only for towing" thingy has become something of an urban
legend.
^^^^^^^^^^^^^^
You are right. Having just bought a used Outback automatic, I have
been reading the owners manual religiously. It says under no
circumstances to tow the car with wheels on the ground. It says to
insert the fuse in case the temporary spare is installed.
 
Dave_Frumkin said:
Can the VC in the center diff be removbed and make the car 2wd.? I
live in TX now not much in the way of snow.

Are you talking about turning diff from viscous-coupled LSD to an open
diff? That won't make the car 2WD. If you gutted the diff to make the car
2WD, it wouldn't be an improvement. If it worked, any change in fuel
economy would be slight, as you're still turning all the driveshafts. And it
would hurt handling: Understeer would increase, especially when powering
through a turn.

Oh, and last time I had trouble in the snow (light RWD car w/summer tires,
couldn't make it up a snowy hill) was in Austin. Texas is also where I did
my most flooded-road driving. I think AWD would be great there.
 
Ross said:
Replace the Diff, Im sure the cost difference would not be much as
opposed to disabling the rear drive and the car would be running as
designed, would have higher resale value, no insurance implications
and be less likely to fail as a result of untested stresses etc. The
car would arguably be more dangerous as the suspension and weight
distribution is set up for AWD not 2WD. The 2wd fuse is there for
towing the AT box Subarus not for driving them.

If you are spending all that labour time in about the drivetrain why
not just replace the diff at a few extra notes and be rest assured
that the mechanics are carrying out a normal routine job not a custom
botch that they will never have had any experience doing.

I was quoted 900$ the for VC only. To just remove the old one was 300$.

Removing the VC does not make the car 2WD as you are not removing the
differential, just the VC unit that connects the two drive axles through two
disks and some silicon fluid. In winter conditions you still have the
advantage that the force transmitted through all four wheels is 1/2 that of
the front wheels of a FWD.

The disadvantage is when you are stuck with one wheel off the ground or on
ice. Normally the silicon in the VC unit heats up and becomes thick, so
some torque gets applied to the axle that is not slipping. Without the VC
this doesn't happen and no torque gets to the other axle. Note if it is a
rear wheel spinning you can get torque to the front wheels by applying the
hand brake!
 

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