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Low Cost LSD Upgrade for Q50/Q60-Install w/ Pics

62K views 221 replies 41 participants last post by  vr30wxrld 
#1 · (Edited)
Disclaimer- I do not work for or am affiliated with the vendor who makes this LSD upgrade kit. I simply wanted to be the guinea pig to try a lower cost option for an LSD upgrade

I had looked at the AMS and Z1 diff upgrades and it seems like they were pretty expensive and in some cases required a core or shipping your center section back, so I began researching alternatives. I found a post where someone confirmed that the rearend in our cars is called the "R190" which has been around for quite some time in 1 form or another. When I searched for R190 LSD, I came across a company called Traction Concepts. They've been around for quite awhile in the racing scene (auto-x, rally, drag, etc.) and sell plate style upgrade kits to convert the 1 tire fire into an LSD for $350. They are made to fit inside the existing diff and apply spring pressure to the gears to keep both wheels turning when torque is applied, but still act like an open diff when there is light throttle or tight turns like in a parking lot. Being that you use the same ring/pinion gears, you don't have to worry preload/backlash/break-in etc. Install and go! I talked at length with their engineer who actually stated how robust the R190 rearend is, particularly with this upgrade. He said he has no concerns with 500/600/700 hp. Here is the process for the tear down and pics of the installed upgrade......

12/25/20 update....4.2 0 to 60. No tune, rwd, JB4 car. This LSD upgrade is holding up great.

9/15/22- Traction Concepts contacted me with some additional info (GOOD INFO) that I'm passing along:

" While the traction performance is the same or possibly superior to other limited slip LSDs and lockers on the market, the design is completely different in the way that it is not a replacement part/diff like the higher priced options. The reason we continue to be compared to the replacement diff options on the market, is because of the results in performance and traction gains our users are getting. We welcome any of the users in your network to reach out and share their experiences with us whether good or bad. Or reach out if they need a better understanding of the product and functions of our design.....

We work alone, without gimmicky accessories, friction plates, or additives and have been in the game doing this for 27 years now perfected and the largest LSD Conversion Company in the world because we are the designers.

When the vehicle manufacturers contact us directly to offer solutions to their OEM set ups for their motorsports teams, we must be doing something right. Currently at this moment in time, we are working with....(ddnspider injection- I won't share which OEM's in the event that they don't want it made public)....


In regards to the different models we offer the LSD + Gear Set, this is a set to be used together, yes. It has been blueprinted as a set. Buyers can keep their original OEM gears or send them back for a core refund (currently for the Qs there is a $199 Core Refund). Or they can ship their Q50 diff to us, and we do the install here and ship the diff back to them paying for the LSD Conversion, gear prep labor, and shipping. We do offer that service you mention as part of the in house install, though they would have to ship the diff."
 
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#2 · (Edited)
Flikr won't let me embed pics, so attached below.

Boy it helps having access to a lift! Here is the view from underneath prior to teardown:
*1st pic*
Make sure the car is in neutral and the parking brake is off.
Begin by taking off the mid-pipe and 2 heat shields along with the cross member.
There are 2 braces- 1 on either side of the diff that must also be removed. Take off the rear sway bar.
Support the rear diff
Mark the rear prop shaft rubber coupler and the final drive companion flange- you must put these back with everything lined up to these marks. Do NOT remove the rubber coupler from the prop shaft. Once its marked you can remove the 3 bolts and gently pry the prop shaft forward to loosen it from the final drive companion flange. Loosen the center bearing mounting bracket on the prop shaft towards the transmission end of the prop shaft. This will allow the prop shaft to slide out of the front of the differential.
*2nd pic* /*3rd pic*
There are 2 large bolts on the bottom of the diff that need to be loosened and 1 horizontal bolt at the top of the diff that must be removed. Support the diff and lower it slightly so you can better access the 2 wheel speed sensors and diff vent tube that must be disconnected.
Get a pry bar and gently pry each of the CV axles out of the diff. There will be tension here so take your time and don't damage anything.
Get that that baby out!
*4th pic*
 

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#148 ·
Hi man. Wondering if you know any shop can install the lsd kit in FLORIDA. Please lmk thanks

Flikr won't let me embed pics, so attached below.

Boy it helps having access to a lift! Here is the view from underneath prior to teardown:
1st pic
Make sure the car is in neutral and the parking brake is off.
Begin by taking off the mid-pipe and 2 heat shields along with the cross member.
There are 2 braces- 1 on either side of the diff that must also be removed. Take off the rear sway bar.
Support the rear diff
Mark the rear prop shaft rubber coupler and the final drive companion flange- you must put these back with everything lined up to these marks. Do NOT remove the rubber coupler from the prop shaft. Once its marked you can remove the 3 bolts and gently pry the prop shaft forward to loosen it from the final drive companion flange. Loosen the center bearing mounting bracket on the prop shaft towards the transmission end of the prop shaft. This will allow the prop shaft to slide out of the front of the differential.
2nd pic /3rd pic
There are 2 large bolts on the bottom of the diff that need to be loosened and 1 horizontal bolt at the top of the diff that must be removed. Support the diff and lower it slightly so you can better access the 2 wheel speed sensors and diff vent tube that must be disconnected.
Get a pry bar and gently pry each of the CV axles out of the diff. There will be tension here so take your time and don't damage anything.
Get that that baby out!
4th pic
 
#3 · (Edited)
Once you have the diff out, drain the oil and start breaking it loose. There are 6 smaller bolts and 4 larger bolts and then just split the 2 halves apart.
*Pic 1*
We took off the ring gear after marking its location so it went back exactly in the same orientation. Here are the machined axle/pin gears.
*Pic 2*
Machined gears back in:
*Pic 3*
LSD upgrade installed with machined gears
*Pic 4*
NOTE- You MUST remove the 2 clips and 4 dowels after the LSD upgrade is installed in the diff. This is what allows the upgrade kit to do its job and let the spring tension push against the gears.
 

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#4 · (Edited)
Once you've got he diff back in the housing, clean off all the grease and dried RTV and put down a light bead of new silicon/RTV. You'll probably have to use a rubber mallet to get the cover back on the diff housing.

Reassembly is the opposite of disassembly. Make sure the CV axles are pushed in all the way and that the C clips were still in place on the axles when you press them back into the housing. You'll have to play with the diff angle and height to get them to slide back in but its not bad. You can reuse the oil seals if they're in good shape.
*Pic 1*
We got the diff back in and used a pump to refill the diff.
NOTE- The service manual says to fill with 2 1/4 PINTS of oil. We ended up with more like 3 pints (1.5 qt) until it dripped out of the fill plug.
Make sure to reconnect the wheel speed sensors and diff vent tube.
 

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#5 · (Edited)
Driving impressions- once we got the car off the lift, I backed out and expected to hear some noise turning or something. NO SOUND. It's like we never did an upgrade at all. Traction Concepts states to take it easy for the first couple hundred miles as well as long slow figure 8s in an empty parking lot so that the kit embeds and "gets to know each other". I did give it to light launches and immediately noticed the sound of TWO tires spinning! I also hit it from a low roll and did NOT get wheel spin which is new to me. So far so good! Once I get a couple hundred miles I'll be comparing the 0 to 60 in the jb4 as well as going back to the drag strip to compare 60ft times.
 
#6 ·
Was going to say you could just edit your Original post but it is probably easier to format sections if they are all separated, that said kudos to you sir
for giving it a shot it will be interesting to see if an affordable LSD modification is achievable.
 
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#7 ·
Thanks for putting in the work to get the community a deal. I put one in my prelude trans and it worked well for the price, withstood many 4k launches, but I was always concerned about the wear it was doing to the hub and gears. It's not a true helical or clutch lsd, and I would be concerned with introducing any extra metal shavings into our weakest point of the drive train. Just my .02
 
#9 ·
I was hesitant myself but after talking with them I felt much more comfortable. They have used these in plenty of makes/models with over 500,000 miles of racing abuse and he specifically said the R190 is NOT a weak link with this upgrade, it's actually robust. He also said he doesn't have a power number where he would be concerned about this LSD upgrade. I guess we'll see how it goes!
 
#10 ·
So this is basically a phantom grip conversion for the diff?
 
#13 · (Edited)
Just make sure to change the diff fluid after a few 1000 miles. That should get rid of the crud the gears polishing in will cause. They look like they need to "work in" some by looking at your pictures.
I'm going to change mine soon as well. That and my transfer case fluid and replace with full synthetic Nissan fluid in the TC and Motul synthetic in the diff.
 
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#14 ·
I updated my driving impressions post. I agree about changing the fluid once everything has gotten to know each other lol. Also considering a thicker oil since I live in a hot climate.
 
#17 · (Edited)
I personally am interested in doing this to my 2015 Q50 3.7.

I don't have the mechanical aptitude to pull this kind of job off myself. Any idea what a shop may charge to do something like this? Or any tech days in the Central Texas area I can attend and get hands on experience with somebody experienced with this sort of thing?

Thanks in Advance.
 
#19 ·
3-4 hrs probably. So what ever the shop rate is X 3-4. (My guess)
 
#20 ·
Pulled a tenth off my best 0-60 (including at the drag strip with no wheel spin) on unprepped surface today by messing with how it shifts and the new LSD...
 
#21 ·
Oh that's pretty impressive considering the fact it was off your best time, so safe to assume 0.2-0.3 improvement in the trap times overall then.
Let us know when you've had a chance to take her on a back-road or on track once shes fully settled.
 
#25 ·
2 wheel burnout confirmed!
 

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#30 ·
We'll I'm not really sure what to make of yesterday lol. It seems like I had TOO much traction. Best 60ft was roughly unchanged. I had messed with boost/shift settings and was able to drop 2 tenths off my best 0-60 and dropped by ET by .2 and picked up 2 mph. Didn't get ANY wheel spin. I think I may be at the limit of what the stock tune can handle as far as how much I can stall it up on launch and minimizing throttle cut at the shift. 12.4@114 isn't too shabby and the rearend had ZERO issues with the LSD upgrade.
 
#31 ·
Hmmm are you still running 17psi peak on 93 octane? If so then deff room for improvement, E20 and 19 PSI should be doable.
 
#32 ·
Yeah, I'm hesitant to add more boost after seeing some people blow theirs and don't feel the juice is worth the squeeze. Still dropping 2 tenths and picking up 2 mph in worse weather is nothing to sneeze at. I really think its all about the launch. I don't think the stock tune will allow me on a RWD to get in the 1.7 or better which is where I really need to be.
 
#33 ·
That's fair I'd probably be plenty happy at 17PSI myself on that engine, but as you said stock tune may be limiting you a bit.
But probably only by another 1-2 tenths, still this LSD Upgrade seems to be well worth it thus far.

A resounding success.
 
#34 ·
Yeah so far pretty happy and the vendor is super responsive to me. After I get 1k miles on it ill do a fluid change and see what it looks like.
 
#41 ·
Yep, 20's are for looks, 18's are all business. 19's are a good compromise.
 
#42 ·
18's all day long for me, if I want to make it look a bit better I'd rather just drop the ride-height a tad. More or less
same appearance and a bit better handling to boot.
 
#44 ·
Ditto.
 
#46 ·
I agreeWWith BigHeadClan who agrees with, who agrees with, oh never mind. Lmaooooo
 
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#47 ·
I disagree with whatever you all are agreeing on...
 
#48 ·
Bumping this up. Been daily driving the car. No noises or issues otherwise. She see's boost typically daily and has been laying 2 stripes of rubber :) 1000 mile diff fluid change is coming up so we'll see what kind of wear is in there from break-in.
 
#49 ·
Excellent looking forward to the update, I suspect there will be a fair amount of metal particulates for this first fluid change.
It's the next fluid change that will really tell us how shes holding up alas that is probably a year away. XD
 
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