VLSD Swapped, Now noise while driving

[S13Enthusiast]

Just swapped in a used 180sx VLSD with axels into my 1990 Base Hatch.

Now when i drive past 2nd gear it makes a whinning noise sort of like how it sounds when your in reverse moving.

The noise stops when I let off the gas, its only when im on the gas i hear it.

It gets louder as I go up the gears, but not louder through the rpm band.

This is not an exhaust leak, I have no idea what it is.

What is this and how do I stop the noise?

Thankyou

[S13Enthusiast]

Are VLSD's supposed to make noise while they are working?

[DRFT]

indeed they are

[S13Enthusiast]

indeed they are


A loud wurrrring sound though?

[sr240mike]

Mine whines, but I also put in subframe spacers and gutted the rear interior at the same time. When you swapped it did you change the gear oil?

[skatanic28]

ive never heard a vlsd make any noise before, so i dont think it should be doing that :confused:

[S13Enthusiast]

Yes gear oil was changed,

Could it be the bearings?

[Redtop_240]

Yes gear oil was changed,

Could it be the bearings?

Did you use LSD oil or gear oil?

They are not the same thing......

[orion::S14]

Did you use LSD oil or gear oil?

They are not the same thing......

And so that we're clear, the OEM VLSD requires no special additives or fluids...only good 'ole 80W-90, GL5 gear oil.

As for the noise, could it be the dust shield at the back of the transmission? Sometimes they come loose and then rub as you drive...makes a high pitch noise typically.

- Brian

[AKADriver]

If it whines only when you're on the power, there's likely a problem with the gears themselves. The VLSD unit isn't doing anything when you're travelling in a straight line and you have traction, and it shouldn't whine. The bearings would make noise at all times. Ring and pinion are most likely. They can be worn if the diff was abused... lots of power, clutch dumps shocking the rear diff.

It could also be CV joints from the new axles.

[Redtop_240]

And so that we're clear, the OEM VLSD requires no special additives or fluids...only good 'ole 80W-90, GL5 gear oil.

As for the noise, could it be the dust shield at the back of the transmission? Sometimes they come loose and then rub as you drive...makes a high pitch noise typically.

- Brian


Are you kidding me? I hope your joking? So why is it that 90 percent of our 240 work is ( i work for a Nissan dealership class A tech 2 classes away from Nissan scope certified...) telling dumb ass who upgrade to a VLSD and take it to jiffy lube that they need a new dif because they ran regular gear oil in there shit? Please expalin? Im curious......

[AKADriver]

I don't know why you do that work, because it's not true. There are plenty of other ways Jiffy Lube can screw up a gear oil job, but this isn't one of them.

The viscous unit is sealed. The only parts of the VLSD to come in contact with the oil in the differential are the ring and pinion, bearings, and spider gears - just like an open diff. The viscous coupling is a series of plates inside a sealed compartment of silicone-based fluid. I'll repeat it a few more times: sealed sealed sealed.

"limited slip" gear oil contains friction modifiers that allow the clutches in a clutch-type diff to do their thing. That's the only difference between "limited slip" gear oil and regular gear oil. Hence, only clutch-type differentials require "limited slip" gear oil. Viscous LSDs don't use friction for the limited slip action. Helical LSDs use the fact that a worm gear can only drive, not be driven, and hence also don't use friction.

[sr20pwrdSiLvIa]

Its your diff bearing, my does the same thing, dont worry about it....

[S13Enthusiast]

Its your diff bearing, my does the same thing, dont worry about it....

diff bearing? are you sure, does it hurt the diff to keep it like this?

i cant drive with a noise that irritating, its loud,

[orion::S14]

Are you kidding me? I hope your joking? So why is it that 90 percent of our 240 work is...telling dumb ass who upgrade to a VLSD and take it to jiffy lube that they need a new dif because they ran regular gear oil in there shit? Please expalin? Im curious......

Becuase you work for a delaership, and if you guys didn't do the work, then you'll tell the customer whatever is needed to get some money out of him/her...maybe not you in particular, but your service manager, or owner, whoever.

Dealership service is a ripoff.

But as for an explanation..."AKADriver" did a fine job of explaining it for me.

- Brian

[S13Enthusiast]

Okay, I understand I have the right fluid in, but what is going on with this VLSD, is it bad if it makes a noise like this?

[max240]

Yea, your fluids fine. Its either a bearing or the meshing between the ring/pinion. I would bet ring/pinion prob because of noise difference when accel., cruising, and decel..

[stinky_180]

did you use an abs drive shaft? or did you some how fit the base model drive shaft on?

[mistaanime]

heh makes noises? i thgouht only aftermarket ones do..heh..anyway..but it's probably juss the bearin..werid..cuz i don't hear anything..from mine..probably the oil i use is pennzoil sycrmesh..

[S13Enthusiast]

did you use an abs drive shaft? or did you some how fit the base model drive shaft on?

It was a non-abs diff, so the driveshaft fit right on.

[S13Enthusiast]

Brought it into the mechanic, said it sounded like a worn ring and pin inside the diff...

[Var]

Brought it into the mechanic, said it sounded like a worn ring and pin inside the diff...


I'd just keep driving on it until it goes out unless you have the skillz to swap another ring&pinion into the carrier.