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Sierra lobro diffs - LSD install
jwhatley - 5/8/13 at 09:07 AM

Hello,

I'm wondering if one of you have the answer to my question, have searched but can't find the info I'm looking for.

I have a 7" 3.14 viscous LSD diff and I have fitted a stronger LSD to it after it ate itself.

Diff all fitted and then I go to fit the stub shafts and they are now the incorrect length, short one is too short and long one is too long - no I haven't got them thr wrong way round!

Does anyone know if the lobro stub shafts are different lengths between the open diff and LSD versions?

I'm hoping I just need to source the other type of stub shaft and I should be ok.

Thanks

John

loggyboy - 5/8/13 at 09:38 AM

What 'stronger' LSD did you fit?

mcerd1 - 5/8/13 at 09:40 AM

quote:
Originally posted by jwhatley
Does anyone know if the lobro stub shafts are different lengths between the open diff and LSD versions?
not that I know of.....

I had the 2 types of 7" side by side for a while (open and ford LSD) and I couldn't see any significant difference (although I never actually measured them)


I assume by 'stronger' you mean you've got a thicker fluid in the LSD bit ?

or have you swapped for a 7.5" diff ?


have you got the correct stub shafts for a ford LSD diff or have you got the stubs for an open diff ?




[Edited on 5/8/2013 by mcerd1]

madteg - 5/8/13 at 09:42 AM

What type of diff is fitted. Quaife or plate.

jwhatley - 5/8/13 at 10:14 AM

Ive fitted a plate type now, i destroyed the LSD at Dunsfold last month.

Stronger as in no gears to destroy! Suppose thats not the viscous bit itself but more the gear set next to it.

It was originally a viscous LSD so i have two bolt on shafts of varying sizes. does the open diff version have the same length shafts? As thats what i think i need.

John

mcerd1 - 5/8/13 at 10:31 AM

which plate type diff have you fitted ?

jwhatley - 5/8/13 at 11:07 AM

3J Driveline NXG

snakebelly - 5/8/13 at 11:48 AM

Has the new diff been fitted to the existing casing?
Have you asked the supplier if any driveshaft mods are required?

loggyboy - 5/8/13 at 12:45 PM

is the new diff intended for push-in shafts rather than Lobros?

jwhatley - 5/8/13 at 02:28 PM

It is ok, we have been working with the manufacturer to get to the bottom of this.

The viscous LSD bolt on stub shafts that go in to the diff are different lengths compared to the open diff due to the viscous housing.

they are the same diameter, material and spline count, but have one long one and one small one. Whereas the open diff has two of equal length.

Thanks

John

rdodger - 5/8/13 at 03:08 PM

If you use the stubs from a non lsd diff they should fit.

jacko - 5/8/13 at 05:44 PM

quote:
Originally posted by rdodger
If you use the stubs from a non lsd diff they should fit.

No they wont
The lsd has one longer then the other side n/side is the long one
A open diff has both the same length
I have just striped one of each type
Jacko

rdodger - 5/8/13 at 05:57 PM

quote:
Originally posted by jacko
quote:
Originally posted by rdodger
If you use the stubs from a non lsd diff they should fit.

No they wont
The lsd has one longer then the other side n/side is the long one
A open diff has both the same length
I have just striped one of each type
Jacko


Sorry if that isn't correct. It was the info I got when considering a Quaife diff. I was told it required equal length stubs from a non LSD Lobro diff.

If that isn't the case then I guess that pisses on my chips if I want the Quaife.

madteg - 5/8/13 at 07:35 PM

Phoned quaife this morning and asked if you could fit 100 lobo stub ends from a none lsd unit. they said yes no problem.

mcerd1 - 5/8/13 at 10:25 PM

quote:
Originally posted by madteg
Phoned quaife this morning and asked if you could fit 100 lobo stub ends from a none lsd unit. they said yes no problem.


+1 TranX and Quaife diff's need the equal length stubs from an open diff so I guess your 3J Driveline NXG one is similar

this is also why you can use these aftermarket LSD's with push-in shafts

only the ford LSD needs the unequal ones

jwhatley - 5/8/13 at 10:26 PM

I think a few people have missed the point here.

I have taken my viscous LSD and replaced it with a aftermarket LSD. Now because ive done that i now need the same length shafts to make it work, as madteg has stated that is also the case with the quaife unit.

This was my original question, which was if there were different size shafts between LSD and open diff. Which i now know the answer.

I just need to source a set of these and i should be back up and running again.

JohnEM - 10/8/13 at 02:32 PM

JohnW
I have, foolishly I now know, purchased an LSD Diff without the output shafts!
If you still have the unequal ones let me know how much you want for them.
JohnEM.

jwhatley - 10/8/13 at 03:12 PM

u2u me and we will sort it out.

John

JohnEM - 10/8/13 at 05:23 PM

JohnW
U2U sent, how many Horses to wreck the Diff?
JohnM

jwhatley - 11/8/13 at 11:17 AM

I was using the car on track on 340bhp, then turned it up to 400bhp map at the time it went bang.

Id say not much over 300 to kill it though.

mcerd1 - 12/8/13 at 08:20 AM

quote:
Originally posted by jwhatley
I was using the car on track on 340bhp, then turned it up to 400bhp map at the time it went bang.

Id say not much over 300 to kill it though.

you must have been unlucky - I know of heavier cars running 500bhp+ on standard diff's