Why should we change the VLSD fluid?

Alstann · 11-30-2013, 11:46 PM

I'm confused as to the purpose of what the OP is asking - I guess the question is more like "what is the reason people change diff fluid?" Rather than if it solely helps VLSD performance.

synolimit · 12-01-2013, 04:54 AM

My testing shows on the highway at 80 mph in the winter for an hour or so my diff fluid reaches 194*. On the track in summer I'm sure it will exceed 300*. I'm hoping my diff cooler will keep the fluid under 250* and allow the VLSD to do its job.

Quote:

Originally Posted by karotZ

It's to ensure functionality, removing the oil ensures that those small shavings don't collect.

That's the magnets job.

kenchan · 12-01-2013, 08:48 AM

Quote:

Originally Posted by kfull

engine oil is overrated....just use crisco

chops · 12-01-2013, 01:31 PM

OP does have a point. considering the fluid inside the diff that makes the diff "lock" is sealed we dont have to change it often. i think the reason you should change it is after extended hard driving. oils break down and lose their effectiveness, and thats the reason i change mine out every so often

wdkwang · 12-01-2013, 03:53 PM

Quote:

Originally Posted by chops

OP does have a point. considering the fluid inside the diff that makes the diff "lock" is sealed we dont have to change it often. i think the reason you should change it is after extended hard driving. oils break down and lose their effectiveness, and thats the reason i change mine out every so often

Thank you.
So basically the diff fluid we put in is just to help cool the vlsd. And as time goes by, the fluid loses it's viscosity and isn't cooling as efficiently, thereby causing the vlsd to overheat quicker and work as an open diff.

Chuck33079 · 12-01-2013, 04:00 PM

Quote:

Originally Posted by wdkwang

Thank you.
So basically the diff fluid we put in is just to help cool the vlsd. And as time goes by, the fluid loses it's viscosity and isn't cooling as efficiently, thereby causing the vlsd to overheat quicker and work as an open diff.

It's gear lube. Its in there to lube the gears. If it helps keep the vlsd alive longer that's a bonus.

wdkwang · 12-01-2013, 04:00 PM

To the ones who left sarcastic remarks, do you even understand how a VLSD works, or how it differs from other LSD's? My thread was to clarify part of the function and maintenance. I don't believe in blindly following a guide without thoroughly understanding why I should do it at all.

Red__Zed · 12-01-2013, 04:01 PM

Quote:

Originally Posted by wdkwang

Thank you.
So basically the diff fluid we put in is just to help cool the vlsd. And as time goes by, the fluid loses it's viscosity and isn't cooling as efficiently, thereby causing the vlsd to overheat quicker and work as an open diff.

wat?

wdkwang · 12-01-2013, 04:02 PM

Quote:

Originally Posted by Chuck33079

It's gear lube. Its in there to lube the gears. If it helps keep the vlsd alive longer that's a bonus.

Thanks for clarifying

Jordo! · 12-01-2013, 04:18 PM

I was about to comment, then it occurred to me that I wasn't sure which parts were directly affected by changing the dif oil either...

Here's an exploded view of the 370Z dif

Which parts are sealed and non-serviceable vs not?

Outer gears are affected by fluid change, whereas inner locking mechanisms are not?

Is that correct?

Rusty · 12-01-2013, 05:48 PM

Ok, looking at that diagram. Part# 38760 is inside the carrier. That would be the VLSD unit that is sealed with silicone fluid. Your gear lube would be seperate from that. The bearings inside the housing is pinion bearing part#38120, and part#38140. 2 carrier bearings, left side and right side, part#38440. Those are lubed with your gear lube.

Alstann · 12-01-2013, 10:36 PM

To clarify - the VLSD uses seperate fluid, that is sealed within the LSD themselves. There is no servicing possible on this device. The diff fluid lubricates the gearing. The VLSD has it's own silicone fluid to act as the coupling.

Jordo! · 12-02-2013, 02:39 AM

^^^ Awesome -- thanks for clarifying, guys! Repped

onzedge · 12-02-2013, 07:56 AM

Quote:

Originally Posted by Alstann

To clarify - the VLSD uses seperate fluid, that is sealed within the LSD themselves. There is no servicing possible on this device. The diff fluid lubricates the gearing. The VLSD has it's own silicone fluid to act as the coupling.

cdoxp800 · 12-02-2013, 08:51 AM

Buy aftermarket Diff. Solves issues

11-30-2013, 11:46 PM	#16 (permalink)
Alstann Track Member Join Date: Oct 2011 Location: South Florida Posts: 882 Drives: 12 PW 370z 6MT Sport Rep Power: 15	I'm confused as to the purpose of what the OP is asking - I guess the question is more like "what is the reason people change diff fluid?" Rather than if it solely helps VLSD performance. __________________ 2012 Pearl White 370Z GReddy Twin Turbo

12-01-2013, 01:31 PM	#19 (permalink)
chops A True Z Fanatic Join Date: Oct 2010 Location: NA Posts: 1,732 Drives: NA Rep Power: 22	OP does have a point. considering the fluid inside the diff that makes the diff "lock" is sealed we dont have to change it often. i think the reason you should change it is after extended hard driving. oils break down and lose their effectiveness, and thats the reason i change mine out every so often wdkwang and Initial Z like this.

12-01-2013, 04:00 PM	#22 (permalink)
wdkwang Track Member Join Date: Nov 2010 Location: N/A Posts: 899 Drives: slidewayz Rep Power: 21	To the ones who left sarcastic remarks, do you even understand how a VLSD works, or how it differs from other LSD's? My thread was to clarify part of the function and maintenance. I don't believe in blindly following a guide without thoroughly understanding why I should do it at all. __________________ Powerhouse Amuse \| K&N Typhoon Intakes \| MotorDyne ART Pipes \| Borla Catback Exhaust \| B&M Short Shifter \| Intake Ducts \| Ichiba 25mm F/R Spacers \| Carbon Fiber Interior Vinyl Wrap \| Tints \| 10000k HIDs \| Vtak, yo!

12-01-2013, 04:18 PM	#25 (permalink)
Jordo! A True Z Fanatic Join Date: May 2010 Location: nirvana Posts: 6,394 Drives: 2023 NATM Rep Power: 418	I was about to comment, then it occurred to me that I wasn't sure which parts were directly affected by changing the dif oil either... Here's an exploded view of the 370Z dif Which parts are sealed and non-serviceable vs not? Outer gears are affected by fluid change, whereas inner locking mechanisms are not? Is that correct? wdkwang and Rusty like this. __________________ Enjoy it. Destroy it.

12-01-2013, 05:48 PM	#26 (permalink)
Rusty Ronin Samurai - Assassin Join Date: Dec 2011 Location: Fayettenam,Pennsyltucky Age: 68 Posts: 35,231 Drives: 2011 Nismo GM 6M Rep Power: 2684438	Ok, looking at that diagram. Part# 38760 is inside the carrier. That would be the VLSD unit that is sealed with silicone fluid. Your gear lube would be seperate from that. The bearings inside the housing is pinion bearing part#38120, and part#38140. 2 carrier bearings, left side and right side, part#38440. Those are lubed with your gear lube. Jordo! likes this. __________________ 浪人 - 殺し屋 "The Difficult Anytime, The Impossible By Appointment Only" http://www.the370z.com/members-370z-...o-journal.html Last edited by Rusty; 12-01-2013 at 05:54 PM.

12-01-2013, 10:36 PM	#27 (permalink)
Alstann Track Member Join Date: Oct 2011 Location: South Florida Posts: 882 Drives: 12 PW 370z 6MT Sport Rep Power: 15	To clarify - the VLSD uses seperate fluid, that is sealed within the LSD themselves. There is no servicing possible on this device. The diff fluid lubricates the gearing. The VLSD has it's own silicone fluid to act as the coupling. onzedge and Jordo! like this. __________________ 2012 Pearl White 370Z GReddy Twin Turbo

12-02-2013, 02:39 AM	#28 (permalink)
Jordo! A True Z Fanatic Join Date: May 2010 Location: nirvana Posts: 6,394 Drives: 2023 NATM Rep Power: 418	^^^ Awesome -- thanks for clarifying, guys! Repped Rusty likes this. __________________ Enjoy it. Destroy it.

12-02-2013, 08:51 AM	#30 (permalink)
cdoxp800 A True Z Fanatic Join Date: May 2009 Location: FL Posts: 1,337 Drives: 2011 Nismo Rep Power: 19	Buy aftermarket Diff. Solves issues __________________ 2011 Brilliant Silver NISMO 370z. #: 0046. PPE LTH \| MillSpec Cats \| F.I Exhaust \| Akuma Intakes \| Rotora 6/4 Brakes

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