Quaife LSD

[Barrykearley]

So - I'm gonna rip the gearbox out at some point in the next coupe of weeks to have the second gear issue fixed. For those that don't know it's been a bit crunchy now and again - and now it's properly buggered off for good - so guessing the dog teeth things have all busted off. Reckon I will change fifth as well.

the question is - while I'm at it - do I sneak in one of these nice diffs?? Are they worth while? Do they make a difference? Thoughts ?

cheers

[swindon_alan]

I've got one of them. Very nice in the dry but I really don't think they are a good idea in the wet or frost in a mid-engined car. You might end up hitting a road sign or something...

[CHANGES]

Uhmm..  A lot depends on the driver, and their ability , and why it is fitted in the first place...  A few points of consideration should be made.  1.  The Quaife unit is an ATB not LSD..  and as such is less aggressive..  2, Either of these types will put more strain on the gearbox as a whole..  3,  Unless you are constantly spinning up a rear wheel under power why do you need one.  4. In the ATB design no undercut is made on the output shafts (for strength reasons) as a result NO 'o' ring is there to butt up against the inner CV spline section to restrict oil flow up the splines. as a result extra care has to be taken to reduce risk of oil leaks. 5. You will require two crown wheel bolts to replace the ones that are special for retention of the planetary shaft on std diff.   6. Fitting one is a professional job requiring shimming the Preload  and Backlash.

As for drivability , they are very good.  When driving aggressively you can really feel the extra stability they give..  Generally If you are not prepared to have the back end step out a bit under power then this may not be for you.. 

As for Barry's questions . Yes they make a difference, not sure how worth while they are on std set up,  But will definitely suite your driving style..    Nothing like a bit of drifting when Plod aint looking..   

     

[Chillidoggy]

Stop messing about and fit some bigger, stickier, rear tyres, then you won't need an LSD.

There, I've just saved you the trouble of getting your ear bent over the amount of Esprit expenditure.

[CHANGES]

I offered him a set of AWI 's with 295's on, along with an after market S4s/V8 arch kit, a while back..   Far to much uhmming  and arhhing going on here..   He needs to get like them chickens.... organised..   (chicken run)    

[Qavion]

It's a pity you don't live in Australia... I'm giving my Quaife LSD away (didn't get around to fitting it before I had to sell the car).

Is there anything in them which breaks down in time if not used? It's been sitting on the shelf for almost 3 years now.

[Chillidoggy]

3 hours ago, CHANGES said:

I offered him a set of AWI 's with 295's on, along with an after market S4s/V8 arch kit, a while back..   Far to much uhmming  and arhhing going on here..   He needs to get like them chickens.... organised..   (chicken run)    

Clucking hell Barry, what are you waiting for?

[swindon_alan]

Eggsactly Ian. I'm sure that Dave is only asking for a poultry amount of money for them? Come on Barry, don't be a coq mate...

[Chillidoggy]

Indeed. I hope he doesn't wait too long, or someone might poach them off Dave.

[Barrykearley]

i am presently haemorrhaging money on this baby...... Plasterer's now in spreading everywhere.

next chicken shed starts on 14th July........

[sailorbob]

Dave, I can understand the need to adjust the bearing preload if the differential is changed but, if the crownwheel and LH bearing are original, wouldn't the backlash remain the same?

Edited June 6, 2017 by sailorbob

[Vulcan Grey]

@sailorbob as you say, if the bearing is retained on the crownwheel and the race is not replaced, then the backlash will be the same, no shim should be necessary.  In my case I opted to replace the bearings and races. However when I checked backlash, no new shim was needed.

The assembly height of the new differential, when compared to the original diff, will be different due to tolerances, so the installer will have to check the differential preload. 

@Barrykearley

If you are already in there, then it's not as big of a job. I really like my Quaife! 

My photos here https://goo.gl/photos/rSGoMePErrxSPLUg9

comments here 

 

I decided to replace both bearings and both races when I installed my Quaife.  The bearings are pressed onto the differential housing and on the crownwheel.

New races pressed in

Preload checked

Differential preload adjusted

[sailorbob]

Thanks Travis, how did you measure the backlash? The service notes aren't the clearest about this to me.

Also, I see in your photo album you used ARP fasteners instead of the OE bolts. How did you install these; dry or with ARP assembly lubricant and to what torque setting?

[Vulcan Grey]

I don't remember what torque I used... Most likely I used the manual setting of

Quote

Torque tighten the crownwheel bolts to 155 - 165 Nm (115 - 135 Ibfft).

I do remember it was difficult to hold the differential when tightening the ARP bolts in the pattern. So I placed steel dowel pins in the holes to prevent it from rotating in the vise.  I don't remember if the ARP fasteners had a different thread pitch than the original Renault bolts...  Also don't remember using ARP lube. So they were most likely oiled.

If you remove and replace the crownwheel bearing or the race in the RH side of the transmission, then the Backlash has to be checked and possibly adjusted.

The backlash adjustment, is a pain, since to adjust it you'd have to remove the bearing from the crownwheel and fit a new shim... under the bearing... and then try again...  The shims are supposed to be chosen by Renault and supplied as a set with a particular crownwheel and pinion. is measured when you assemble the housings dry (no sealant) and bolt it together.  Then you use a dial indicator or test indicator on the crownwheel and manually push it sided to side rotate the crownwheel each direction till it hits the pinion while noting how much the indicator says the differential is moving (Section FG.19 in the manual).  It would probably be best not to replace the bearing on the crownwheel for this reason!   I'n my case I got lucky, and my differential did not have a shim, and my original shim was correct for the proper backlash with the Quaife...  No guarantees for anyone else though!  I probably would have made a shim if a new one was required.

Quote

Check the crownwheel backlash at 3 points 120” apart.
Specification: 0.1 - 0.2 mm (0.004 - 0.008 in).
If out of specification, refer to Sub-Section FG.15.

Backlash would be measured similar to crank end thrust.  It's radial not axial.

 

[sailorbob]

Unfortunately there are two sets of values in the service notes for the crownwheel bolt torque settings

Page 31 - 155 - 185 Nm (115 - 135 lbf/ft)

Page 34 - Stage 1 @ 70 Nm, stage 2 @ 170 Nm

I'm not sure if these are meant for the standard differential and the torque biasing differential respectively or if the latter specification is an update that covers both types.

OK so it sounds like the service notes ought to be a bit more specific and it's axial backlash rather than normal or radial etc. That makes it clearer to me thanks. The rather poor diagram in the service notes showing the position of the dial gauge doesn't help in figuring this out.

 

 

[Vulcan Grey]

actually you jogged a memory (I did this in 2009), it is radial backlash, traditional gear backlash. I think I did jiggle the crownwheel against the pinion back and forth, not the entire differential axially.  I'll strike-out what I said above.

The torque is usually specified for the bolt diameter, thread pitch, and whether lubricated or not.  It is possible that the ARP bolts used a different thread pitch, since they do oh the Lotus 910 head bolt studs (clamping the head, the threads into the block are the same as Lotus).

 I can't remember if I received torque specs from the vendor selling the ARP fasteners or not, but looking back at an email, I apparently tightened the ARP bolts to 130ft-lbf.

And it looks like I did re-use the original shim.

 

[CHANGES]

3 hours ago, sailorbob said:

Dave, I can understand the need to adjust the bearing preload if the differential is changed but, if the crownwheel and LH bearing are original, wouldn't the backlash remain the same?

 

1 hour ago, Vulcan Grey said:

I'n my case I got lucky, and my differential did not have a shim, and no shim was needed for the proper backlash with the Quaife...  No guarantees for anyone else though!  I probably would have made a shim if one was required.

As it turned out when I did mine the backlash did need attention. Not a lot , but it so important to get this correct or your CWP will go south quickly.

46 minutes ago, sailorbob said:

Unfortunately there are two sets of values in the service notes for the crownwheel bolt torque settings

I used 135 lbs/ft  

[Vulcan Grey]

The Renault UN1 manual shows a little more clearly that the dial indicator is touching the tooth of the crownwheel when measuring backlash.

 

[sailorbob]

Thanks for the info guys, it's most helpful.

[qwerty123]

I have one fitted, I've done track days and racing with and without it. I'd say that the performance comes into its own coming out of bends where you can get away without losing energy through the spun up inside wheel. On the open diff you really do have to wait until it gets traction before nailing it and it seems like an age before blast off...Also the inside wheel will spin up regardless of having sticky tyres on, just you'll do it at slightly higher speeds.

With the Quaife fitted I don't really notice it until the back lets go, then you have to be quick because both tyres have lost grip and again you're at higher g-loads and speed.

It's controllable though ;-)

When racing I am on boost most of the time so I don't worry too much about the turbo lag. On the road, on a cold, wet Sunday morning where you might not be the most alert, I'd be careful.

Edited July 18, 2017 by qwerty123

[andyblackman777]

Ive been told its ok to reuse the crown wheel  bolts, but i'm rather dubious about this. trouble is  I'm finding it hard to source new oem ones??

Ideas/thoughts

Cheers

 

[andyblackman777]

Steve at SJ says they are now obsolete

[Vulcan Grey]

On 02/05/2023 at 05:54, andyblackman777 said:

Ive been told its ok to reuse the crown wheel  bolts, but i'm rather dubious about this. trouble is  I'm finding it hard to source new oem ones??

Ideas/thoughts

Cheers

 

I bought new bolts for my quaife crown wheel. They look like ARP. 

I bought them from JAE in California. GTO in Wales should also have them I would think.

 

[MrDangerUS]

Looks like ARP clutch bolts PN# 147-2802, M12x1.25mm. They are spec-ed out for Dodge Cummins 5.9L Diesel

[andyblackman777]

I ordered the ARP ones from JAE luckily they sell them individually. Wouldn't want to buy two packs at $80 as you need 10 and 8 in a pack

Thanks guys