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Discussion Starter #1
So wanted some input.
Found out I have a LSD in my diff
A01A 200mm
Believe it's a Cusco RS
Issue I'm having is that when turning at low speed there is a LOUD audible clunking noise under load only.
If you take the turn without load, no noise.
Just replaced all bushings related to the diff...
Any thoughts on how to quite this up? Using Mobil 1 diff oil.
I didn't know if a friction modifier would help or if anyone had any thoughts?
252509

252508
 

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I would recommend Amsoil Slip-Lok limited slip additive, but that looks like a gear type limited slip, no?

A gear shop I am working with puts Lucas conventional 85W-140 in everything. They claim it "climbs" the gear to above the oil level and keeps the gear cooler - just like it does in those display things in Advance Auto with the little gears. They said synthetic is too slippery. I am about to switch to it.

Al
 

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This is very common with "clutch type LSD's", after spending years on racetracks on drift events i heard these noises all the time. A friend of mine has a Kaaz LSD in his S13, it has the exact same noise as you describe and he's never had any issues with it's operation. If it truly is supposed to make this noise though i'm not sure, all i can tell you is it's very common. I believe the noise comes from the clutch packs engaging and the diff "locking" which it is designed to do under load (hence why it's all quiet with no load). It can probably be resolved by making the clutch packs engage less aggressively (i believe this can be adjusted on these types of LSD's).

For the record, I'm not by any stretch a professional in regards to differentials, but from how i understand these units operate this is what happens and what can be done.
 

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This is very common with "clutch type LSD's", after spending years on racetracks on drift events i heard these noises all the time. A friend of mine has a Kaaz LSD in his S13, it has the exact same noise as you describe and he's never had any issues with it's operation. If it truly is supposed to make this noise though i'm not sure, all i can tell you is it's very common. I believe the noise comes from the clutch packs engaging and the diff "locking" which it is designed to do under load (hence why it's all quiet with no load). It can probably be resolved by making the clutch packs engage less aggressively (i believe this can be adjusted on these types of LSD's).

For the record, I'm not by any stretch a professional in regards to differentials, but from how i understand these units operate this is what happens and what can be done.
Thanks sir.
I'm personally going to take the car for a drive this weekend and probably make a video as well.
New to this platform and making this car mine by upgrading things here and there

252583
 

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Happy to help. The stock torsen diff's are by far the best differentials on these cars, even over the TRD units, which are a downgrade in my opinion.
 

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Also, ch
Happy to help. The stock torsen diff's are by far the best differentials on these cars, even over the TRD units, which are a downgrade in my opinion.
Thats a big call haha

What do you like about the Torsen, and not so much about the TRD?
 

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Also, ch

Thats a big call haha

What do you like about the Torsen, and not so much about the TRD?
Torsen, or all geared/helical differentials (Torsen is one "brand", there are others too) are superior in design to "regular LSD's", at least generally speaking. The torsen differential's operation is very different from a regular differential, I'm not going to try and explain how everything inside it work as there are a bunch of good articles on this that can be found on the internet. The main difference between a torsen and a regular differential is that it acts as an open differential if the torque applied to both wheels are the same, but if one wheel encounters wheelspin the torsen will bias torque to the wheel with grip, hence the name torsen (Torque Sensing). This makes the differential unique in "finding grip" while cornering since it will transfer more torque to the wheel with the most grip, the amount of torque difference that can be had is determined by the bias ratio the diff was designed with. This makes the diff very smooth and dynamic in operation and makes the diff perform well in a lot of different scenarios. If one wheel starts to loose traction in a corner, the differential will put more torque on the other wheel up until the point that both wheels loose traction and spin, when both wheels loose traction and spin the diff operates the same way as fully locked clutch type LSD since both wheels are spinning, in other words now have the same amount of grip, therefore no bias is applied and both wheels get the same amount of torque. Because of this dynamic operation a torsen diff "locking up" is much more linear and smooth compared to a regular LSD. Other advantages to geared/helical differentials is that they make less noise and require very little maintenance. Regular LSD's have clutch packs inside them to provide the lock, which mean they require "special" additives in the diff oil for the clutch packs to operate as intended. This additive in the oil gets broken down over time, and if not changed regularly result in a diff that operates poorly or one that won't lock at all, hence the higher maintenance required on a regular LSD. The clutch packs can also wear out completely, especially if driven for extended periods of time with the wrong oil, or old oil where the LSD additives have been broken down.

Now, the torsen has a few downsides to the regular LSD, but none of them apply to a street car in my opinion. If one of your wheels get stuck in the air, the one in the air will just spin, and the one on the ground will not receive any toque, meaning you are stuck. But if this scenario happens to a supra you have other concerns i would imagine. The other "downside" is that, if you are unhappy with your torsen's operation (highly unlikely) and want to tune the torque bias for example, this is not very straight forward. On a regular LSD though it is "fairly easy" to tune how the diff operates with pressure angle, preload, type of friction plates etc.

Could you tune your regular LSD to operate as good as a torsen in most scenarios? Probably, but you would have to pull the diff and change specs/parts in between each scenario, this combined with higher maintenance and noise is the reason i think gear/helical differentials are superior in a regular road car.
 

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Happy to help. The stock torsen diff's are by far the best differentials on these cars, even over the TRD units, which are a downgrade in my opinion.
Although the Torsen sounds great on paper, and is good for a lot of cars, you must have never driven, or ridden in a high HP Supra with one?

What happens is when you get a sudden surge of torque when the boost hits at a high speed, the back end kicks out to the left. So imagine kicking it in 2nd gear, here comes the boost, and the back end kicks out at 55 MPH! When I say "kicks out", I mean completely to the side, requiring you to let off the throttle and counter-steer.

It is scary, to say the least. A panicked person that hits the brakes in that scenario may end up off the road. Admittedly, this tended to only happen in cold weather, but I do run drag radials full time. I can only imagine what someone with street tires would experience in the same scenario. Probably the same thing, but at 80 MPH!

Since I changed to a TRD diff, if I lose traction, the car spins straight with an occasional slight kick to the side VS 90% of the time for the Torsen. Also, many Supra owners have broken the Torsen, including me. So there is a horsepower limit for them.

Getting back to the OP's car, a clutch type diff should not make a clunking noise when hitting the throttle, when the clutches "lock". There may be a specific brand that does, but it's not typical.

Al
 

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I'm curious if someone has an aftermarket torsen dif that is upgraded over the torsen available from Toyota.
 

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Although the Torsen sounds great on paper, and is good for a lot of cars, you must have never driven, or ridden in a high HP Supra with one?

What happens is when you get a sudden surge of torque when the boost hits at a high speed, the back end kicks out to the left. So imagine kicking it in 2nd gear, here comes the boost, and the back end kicks out at 55 MPH! When I say "kicks out", I mean completely to the side, requiring you to let off the throttle and counter-steer.

It is scary, to say the least. A panicked person that hits the brakes in that scenario may end up off the road. Admittedly, this tended to only happen in cold weather, but I do run drag radials full time. I can only imagine what someone with street tires would experience in the same scenario. Probably the same thing, but at 80 MPH!

Since I changed to a TRD diff, if I lose traction, the car spins straight with an occasional slight kick to the side VS 90% of the time for the Torsen. Also, many Supra owners have broken the Torsen, including me. So there is a horsepower limit for them.

Getting back to the OP's car, a clutch type diff should not make a clunking noise when hitting the throttle, when the clutches "lock". There may be a specific brand that does, but it's not typical.

Al
Ive been around countless 1000hp supras over the years. I did drifting and time attack for about 5 years, and most supras that were on the track all ran the stock torsen.

My post were made with no specific application in mind, and as my statement hinted to, other types of differentials might be better for specific applications. High horsepower drag racing is a specific application in my mind.

Also, comparing the stock supra torsen to other differentials that were designed to run on very high horsepower is not fair in my opinion. There are plenty of gear/helical differentials that handle high horsepower very well like quaife and truetrack to name a few.

Nowhere in this thread did the OP state that his car is tailored for high horsepower drag racing, so i made my statement on a general basis, not specific to any application.
 

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Getting back to the OP's car, a clutch type diff should not make a clunking noise when hitting the throttle, when the clutches "lock". There may be a specific brand that does, but it's not typical.
I installed a TRD LSD in my 1995 NA and it also makes a clunking noise. I think it needs to be adjusted but I don't know how to do it.
 

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I have the OS Giken in my Mk3, and have occasionally had the clunking noise. Seemed to only happen in one place, a slightly uphill, right hand turn, from a stop sign on my way home. Other than that, and maybe one other place, I've only heard it a few times. It's definitely disturbing to hear, but I haven't heard it in so long that I never thought I needed to look into it.
 

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As i said in my first post, this is very common on most clutch type LSD's (just google "lsd clunking noise"), it is so common in fact that Kaaz has a dedicated "silent" version of the same LSD.

I thought the OS Giken units was noise free though since most of them have a pretty different design than "the usual" LSD's. And yeah, it is definitely disturbing to hear, in my friends S13 track car with solid bushings on all diff mounts and all suspension parts in the rear it sounds like the diff is about to come exploding through the car. Never had any issues with it though, and he's had it since it was his daily driver, almost 15 years i believe.
 

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I have a question that is on the same topic (perhaps). Which Toyota OEM Torsen-type LSD will fit in the 1995 NA differential housing (without changing axle shaft length, pinion or ring gears)? My guess is the LSD from a 1995 Twin-turbo with an automatic transmission.
Next question is how to obtain one and identify it to make sure what it is?

* Before you tell me there's a thread on this, I will inform you that I read it and I still don't know that answer. *

Here are some examples that I found on ebaby:
Toyota Genuine JZX100 1JZ-GTE Torsen LSD Differential JDM From Japan F/S (*no part number given)
2001-2005 OEM Lexus IS300 Automatic LSD Limited Slip Differential M98 |S6438 (*can't find this part number)
Toyota genuine JZS161 Aristo 2JZ-GTE Turbo Differential Final 3.8 JDM (*no part number given)
Toyota Aristo GS300 JZS161 Genuine Differential Final 3.8 JDM From Japan F/S (*no part number given)
JDM 93 94 95 96 97 TOYOTA SUPRA JZA80 MK4 2JZ-GE 5 SPEED M/T REAR DIFFERENTIAL (*has the word "LSD" painted on it)
JDM 1993 - 2002 Toyota Supra MK4 Aristo Torsen LSD Rear Differential Only 4.08 R (* this one looks correct at least)

I think this is enough to illustrate the problem...
252605
1594991493976.png
 

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This video seems to give accurate information regarding clutch-type LSD units:
Limited Slip Differentials: LSD Selection, Setup, and Tuning
Decent video on clutch type LSD's. Just as i said earlier in this thread, this video also shines good light on the fact that you have to set up a clutch type LSD differently to be good at a specific application. This is why i made my original statement that i think the torsen, or any gear/helical diff, is the best for a multipurpose road car. The torsen is going to be good in all applications, it won't be the best for all of them, but is going to perform great generally speaking. The clutch type LSD on the other hand, need to be set up again if the car is taken from a time attack event to a drag racing event the next day to perform optimal.
 

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I have a question that is on the same topic (perhaps). Which Toyota OEM Torsen-type LSD will fit in the 1995 NA differential housing (without changing axle shaft length, pinion or ring gears)? My guess is the LSD from a 1995 Twin-turbo with an automatic transmission.
Next question is how to obtain one and identify it to make sure what it is?

* Before you tell me there's a thread on this, I will inform you that I read it and I still don't know that answer. *

Here are some examples that I found on ebaby:
Toyota Genuine JZX100 1JZ-GTE Torsen LSD Differential JDM From Japan F/S (*no part number given)
2001-2005 OEM Lexus IS300 Automatic LSD Limited Slip Differential M98 |S6438 (*can't find this part number)
Toyota genuine JZS161 Aristo 2JZ-GTE Turbo Differential Final 3.8 JDM (*no part number given)
Toyota Aristo GS300 JZS161 Genuine Differential Final 3.8 JDM From Japan F/S (*no part number given)
JDM 93 94 95 96 97 TOYOTA SUPRA JZA80 MK4 2JZ-GE 5 SPEED M/T REAR DIFFERENTIAL (*has the word "LSD" painted on it)
JDM 1993 - 2002 Toyota Supra MK4 Aristo Torsen LSD Rear Differential Only 4.08 R (* this one looks correct at least)

I think this is enough to illustrate the problem...
There is a lot of information HERE that might be of help to you, scroll down until you find the "differential" section. There is also good info on what codes are on the different differentials and what they mean in there somewhere.
 
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