Hi everyone, I'm a total newb to the car modding scene and
was doing a little research on the 4.08 FD mod.

I'm looking to get it done to my car but I also want an after market LSD to go with it.

Doing some research, I've narrowed it down to Quaife as my brand of choice.

However I noticed that one of the vendors on this forum sells two versions for the g37 6MT.

https://www.myg37.com/forums/engine-...ood-price.html

Part #:QDF11L (Manual open rear end)
Part #:QDF13L (Viscous diff replacement)

Can someone enlighten me about the difference between the two?

I drive a 08 g37s coupe if that helps.

Thanks!

 

One is for a manual trans equipped car, the other is for an auto trans equiped car.

The ad is misworded.

Search: Cars, 350Z, Nissan, Differentials - Quaife Engineering

 

Getting what I can from reading the info on the link provided I see nothing about
the QDF13L (Viscous diff replacement) being for only automatics.

I see that the
QDF10L (Auto.) is only for auto.

I'm wondering about the difference between
QDF11L and QDF13L

 

13 is a direct viscous replacement for both.

11 is a helical LSD for manual trans
12 is a helical LSD for auto trans


Why bother replacing a viscous for a viscous.
Even with helical the benefits shine on the track, not street driving.

 

Mainly because most viscous lsds, especially stock ones are dead after 50k miles and run like open diffs.

Plus the stock one doesn't handle the power very well and burns up, which also kills it quickly and reverts it back to open diff.

 

My statement was meant to state, why replace viscous with viscous, while your spending money for a swap, then get a true helical.

 

If I remember correctly Part #:QDF11L (Manual open rear end) is for cars that have an open diff from the factory. I remember seeing something about the hub length being different between the two. Longer hub is this one if I remember correctly.

Part #:QDF13L (Viscous diff replacement) This is for cars that came with a viscous slip in the first place and replaces it again, the only difference is the hub length for the two.

11 is for cars with an open diff, 13 is for cars that came with the limited slip.

 

Open diffs and VLSD have different axle stubs so that is the part number difference. Jack you rear up and spin one wheel and if the other spins the opposite direction you have a VLSD.

I run a quaife it is a great diff if you do lots of street driving it doesn't lock up like clutch style LSDs. Mine has held over 610ftlbs of torque at the rear wheels.