NSX differential

[NoelWatson]

Anyone know what type of diff my 2004 coupe manual car has? Reason I ask is that my car was unable to pull away on an incline on the way home yesterday. The left wheel was on leaves and was spinning. The right was doing nothing. I am thinking it is a torsen type diff - if so I should've used the handbrake to transfer torque.

After 11000 miles, I think my RE040s on the rear have seen better days.

[NSXGB]

Sounds very strange. Firstly the LSD should have transferred power from the spinning wheel to the other side and then if either of the wheels are still spinning the TCS should have atempted to help (if you had it on).

[NoelWatson]

Sounds very strange. Firstly the LSD should have transferred power from the spinning wheel to the other side and then if either of the wheels are still spinning the TCS should have atempted to help (if you had it on).

The LSD did help, but we were on an incline so not enough torque was transferred (if I remember correctly, torsen types have a max transfer ratio i.e 4:1). Traction control (for later cars) is very aggressive - good for saving hamfisted drivers, but not good for pulling away on slippery surfaces. Had a similar problem back in April in the snow.

[simonprelude]

My Merc did the same yesterday

[markc]

I'm pretty sure it's not a Torsen diff. Torsen diff are not usually fitted to RWD cars as they're better suited to FWD or 4WD cars.

I don't think they changed the diff type for the 02+ cars so it should be a traditional LSD with friction clutches transferring the power when one wheel starts to spin.

This type of LSD relies on input torque (from the engine/gearbox) and driveshaft load to "lock" the output to both wheels though clutches which are fitted to each driveshaft. The torque/load causes the friction clutch packs together thus driving both wheels.

The NSX LSD is not a tight one (like the ones fitted to the S2000) so does allow some slip between wheels. Your description does sound quite extreme though. The clutches eventually wear out and require replacing or reshimming to restore correct operation.

When was the gearbox/diff oil last changed? Might be worth having it changed as it effects the operation of the diff.

Cheers

Mark

[NoelWatson]

I'm pretty sure it's not a Torsen diff. Torsen diff are not usually fitted to RWD cars as they're better suited to FWD or 4WD cars.

I don't think they changed the diff type for the 02+ cars so it should be a traditional LSD with friction clutches transferring the power when one wheel starts to spin.

This type of LSD relies on input torque (from the engine/gearbox) and driveshaft load to "lock" the output to both wheels though clutches which are fitted to each driveshaft. The torque/load causes the friction clutch packs together thus driving both wheels.

The NSX LSD is not a tight one (like the ones fitted to the S2000) so does allow some slip between wheels. Your description does sound quite extreme though. The clutches eventually wear out and require replacing or reshimming to restore correct operation.

When was the gearbox/diff oil last changed? Might be worth having it changed as it effects the operation of the diff.

Cheers

Mark

http://www.nsxprime.com/forums/showt...ghlight=torsen

http://www.nsxprime.com/forums/showt...ghlight=torsen

So I think both pre and post 97 cars use clutch plates as you say, but with slight differences. I will get all fluids changed at my next service - not sure when this was last done.

[Kaz-kzukNA1]

Just a follow up. This is what inside your LSD.

As Mark stated, it is based on multiple friction disks (clutch) and not the ‘Torsen’ one.
These disks are soaked in the MTF and as NSX has quite small oil capacity considering its performance and with the ingenious way of circulating the oil for the mechanical parts inside the GBox, the MTF needs to be looked after very well.

Depending on how you drive the car, these disks will eventually wear out and loose the original locking torque. What you experienced was exactly the tendency of standard NSX LSD. The one on Type-R got higher locking setup.

If you have a big socket and torque wrench, you can check the status of your friction disks and understand the torque required to break the locking. You may find it quite low but servicing of LSD requires SST...

Regards,
Kaz

[NoelWatson]

Just a follow up. This is what inside your LSD.

As Mark stated, it is based on multiple friction disks (clutch) and not the ‘Torsen’ one.
These disks are soaked in the MTF and as NSX has quite small oil capacity considering its performance and with the ingenious way of circulating the oil for the mechanical parts inside the GBox, the MTF needs to be looked after very well.

Depending on how you drive the car, these disks will eventually wear out and loose the original locking torque. What you experienced was exactly the tendency of standard NSX LSD. The one on Type-R got higher locking setup.

If you have a big socket and torque wrench, you can check the status of your friction disks and understand the torque required to break the locking. You may find it quite low but servicing of LSD requires SST...

Regards,
Kaz

Kaz,

Thanks for that. Not sure when my tranmission oil was last changed - I don't know when it comes up in the servicing schedule.

[Ewan]

Kaz,

Thanks for that. Not sure when my tranmission oil was last changed - I don't know when it comes up in the servicing schedule.

Noel: from memory, it's at the 6 year interval. Last service for me (5 years), I bought new transmission oil from OpieOils and got them to replace it because I was getting a notchy shift from 1st-2nd when cold. Replacing the oil made a bit of a difference though it's still a bit clunky at first.

cheers
Ewan

[NoelWatson]

Noel: from memory, it's at the 6 year interval. Last service for me (5 years), I bought new transmission oil from OpieOils and got them to replace it because I was getting a notchy shift from 1st-2nd when cold. Replacing the oil made a bit of a difference though it's still a bit clunky at first.

cheers
Ewan

I was going to ask about what I would need to a full fluid change after seeing OpieOil's latest offer. So in addition to engine oil and transmission fluid, is there anything else?