Tightening a Subie LSD

[compression]

I am running a subie LSD from an SVX in my 610. Problem is, it needs to be tightened up. I am getting one-wheel burnouts.

I know its an LSD because I have had the cover off before and I could see the clutch pack. Is there an easy way to tighten it? or do I have to take it a professional at a driveline shop?

[datzenmike]

It may need a re-build kit with new discs and plates.

 

You are using the special LSD oil right? It's not the same as 90W usually used in rear ends.

 

Also try this first... find a parking lot and slowly make 10 left hand circles then 10 right. Back 'in the day' posi rears would chatter or slip from driving in straight lines and the oil would drain off the clutches. Circles will force oil onto the clutches and MAY help solve your prob. (long shot but cheap to try)

[compression]

yep, I am using LSD oil. I will try the circle thing. if that fails, out if comes for a rebuild. thanks

[bru73]

i am a subaru mechanic that dif can be rebuilt only if you have the special tools from kent-more they are very pricey best bet is to replace the unit rec useing a sti dif

[69FJWagon]

you can change the break away pressure on one of those (SHIM IT) I have not done it personally but I have seen Troy (Click the link) do it more than once and it helped out alot but if the clutches are to far gone its gunna feel good for a while but the end result will be the same..ONE WHEELER PEELER :lol: and he uses every day tools to do so nothing special.

 

Clayton

[bru73]

4. Limited Slip Differential (LSD)

Aviscous coupling (VC) type LSD has been adopted so

as to ensure safe and smooth transfer of increased

power under various driving conditions . This VC type

LSDfeatures ease of turning while maintaining excellent

stability when driving over slippery roads or when using

engine brake, thus enabling engine power to be utilized

efficiently. Smooth restriction of the differential operation

of the left and right wheels results in improved

running stability on bad roads, snowy roads, and also

on muddy roads .

1 . STRUCTURE

The VC type LSD adopts a "shaft to shaft system" in

which the RH and LH rear drive shafts are coupled by a

VC. This results in a compact structure with high performance.

The inside of the VC housing is formed by alternately

combining the outer plates (the outer periphery of each

plate engages with the internal spline of the housing)

and inner plates (the inner periphery of each plate

engages with the outer spline of the hub).

On the outer periphery of the outer plate, the spacer

ring is fitted and set in position. On the inner plate, no

positioning ring is used : The plate can be moved a

certain amount on the hub spline in the axial direction .

Sealed inside the housing is a mixture of high viscosity

silicon oil and air. The housing is sealed by X-rings so

that silicon oil will not leak into the rear final drive even

when the pressure increases dueto a greater difference

in the rotation speed between LH and RH wheels.

The spindle (LH) which is integral with the rear drive

shaft (LH) is coupled by the VC case spline, and is fitted

to the side gear (LH) which is integral with the VC case.

The spindle (RH) which is integral with the rear drive

shaft (RH) is spline fitted to the side gear (13H). The end

of the spindle is fitted by splines to the VC hub. No

disassembling of the VC is allowed.

Side gear (LH)

Side gear (R H)

v -

Pinion shaft

Pinion gear

Drive gear

Viscous coupl i ng

C3-129

Fig. 5

2. OPERATION

1) When right and left wheels turn at equal speed

During normal straight-road driving where the right and

left wheels run at an equal speed, the differential case

and side gears rotate together, just as in conventional

differentials. As a result, driving torque is transmitted

equally to the right and left side gears as shown in

Figure 6.

5

[bru73]

1 . Rear Differential

Symptom and possible cause Remedy

Oil leakage

" Worn, scratched, or incorrectly seated front or side oil seal . Scored,

battered, or excessively worn sliding surface of companion flange .

Repair or replace.

Clogged or damaged air breather . Clean, repair or replace .

Loose bolts on differential spindle or side retainer, or incorrectly

fitted O-ring .

Tighten bolts to specified torque . Replace O-ring .

Loose rear cover attaching bolts or damaged gasket. Tighten bolts to specified torque . Replace gasket and apply liquid

packing.

Loose oil filler or drain plug . Retighten and apply liquid packing .

" Wear, damage or incorrectly fitting for spindle, side retainer and oil

seal .

Repair or replace.

Seizure

Seized or damaged parts should be replaced, and also other parts should be thoroughly checked for any defect and should be repaired

or replaced as required .

Insufficient backlash for hypoid gear . Readjust or replace.

Excessive preload for side, rear, or front bearing . Readjust or replace.

Insufficient or improper oil used. Replace seized part and fill with specified oil to specified level .

Damage

Damaged parts should be replaced, and also other parts should be thoroughly checked for any defect and should be repaired or replaced

as required .

Improper backlash for hypoid gear . Replace .

Insufficient or excessive preload for side, rear, or front bearing . Readjust or replace.

Excessive backlash for differential gear. Replace gear or thrust washer.

" Loose bolts . and nuts such as drive gear bolt . Retighten.

Damage due to overloading . Replace .

Noises when starting or shifting gears

Noises may be caused by differential ASSY, universal joint, wheel bearing, etc. Find out what is actually making noise before disassembly .

Excessive backlash for hypoid gear . Readjust .

Excessive backlash for differential gear. Replace gear or thrust washer.

Insufficient preload for front or rear bearing . Readjust .

Loose drive pinion nut . Tighten to specified torque .

Loose bolts and nuts such as side bearing retainer attaching bolt. Tighten to specified torque .

35