Is this normal for a Torsen Differential
12-26-23, 06:19 PM
#1
Rookie
Thread Starter
Is this normal for a Torsen Differential
I am having problems with what feels like a differential that has too much loose play in it somewhere. It clunks when I press the accelerator and let off. The problem is I don't know if what is happening is actually normal or not. I attached two files comparing my oem open differential and the diff with the Torsen inside.
A rear end diff shop transferred the Torsen to an LS differential, and set everything to what I assume was the proper settings. I took it to a transmission shop where the owner said it was normal and probably due to the single mass flywheel in the transmission.
Watch the video's and let me know what you think.
1992 Lexus SC400
CD009 Transmission
I had a rear end specialty shop remove the Torsen from an SC300 (4.272:1) and put it into a 2001 LS430 (3.266:1) differential
One piece aluminum drive shaft
A rear end diff shop transferred the Torsen to an LS differential, and set everything to what I assume was the proper settings. I took it to a transmission shop where the owner said it was normal and probably due to the single mass flywheel in the transmission.
Watch the video's and let me know what you think.
1992 Lexus SC400
CD009 Transmission
I had a rear end specialty shop remove the Torsen from an SC300 (4.272:1) and put it into a 2001 LS430 (3.266:1) differential
One piece aluminum drive shaft
12-26-23, 11:38 PM
#2
I have a 200mm Torsen Type-1 LSD in my SC300. I'm not a driveline specialist and had my diff built with the same use Supra MKIV TT Auto Torsen T-1 two different times with two different gear ratios (first with a 4.272:1 ring and pinion for naturally aspirated use and the second time back to its original 3.769:1 ring and pinion for turbo use).
My last diff builder checked all tolerances and installed all new bearings. He also checked the tolerances inside the T-1 Torsen and said that things were still in spec and that realistically with my non-track driving I could expect at least another 150k-200k out of it if not more.
I have a little initial clunk noise sometimes when I take off from a dead stop (also with an R154 5-speed transmission with an OS Giken twin-disc clutch) but other than that my Torsen makes no additional noise that I hear.
But I think that depending on total cumulative use, abuse and wear and tear if it's always been driven on very hard even a Torsen T-1 (or T-2) can eventually develop too much play in its worm and spur gears. I am not studied on how to disassemble, measure tolerances and reassemble a Torsen LSD but this is what I have been told.
However these LSDs are designed to have VERY long service lives so this kind of wear usually takes a very long time... or a lot of cumulative lifetime abuse... or a heck of a lot of power (torque) from the drive-line going into its gears.
...
Only you can say for sure how poorly your Torsen is feeling in real world use. A diff technician could inspect its internal play with the cover off. Is it doing any newly unpredictable as to behavior compared to how it used to behave?
After viewing both your videos I went over to a spare good condition 92-97 SC400 3.92:1 open diff that I have sitting around which I used in my SC300 for a short time. I checked for the play you demonstrated and it has none of it. When I last installed my rebuilt MKIV TT Auto 3.769 Torsen T-1 LSD diff it also had none of that play you demonstrated.
I cannot tell you if what you are noticing is the Torsen LSD center itself showing an issue or if it is just excessive play in the ring and pinion in your donor LS430 3.26:1 diff which the Torsen was installed into.
Another question would be whether or not you noticed any of this same play before you installed the freshly rebuilt diff pumpkin into your SC?
...
Any one piece driveshaft will transfer more oscillations through the drive-line compared to a factory two-piece driveshaft. I have retained a factory Toyota two piece driveshaft in my car but its front section was modified for my transmission application and I can say that it has been very smooth in operation with both single mass flywheels in W58 and R154 5-speed transmissions and with a twin-disc clutch with integrated flywheel in that same R154 transmission.
I am not so certain that using a single mass flywheel with your CD009 transmission would be able to cause excessive play in the rear differential all on its own.
It's *possible* that the one-piece driveshaft, if too heavy and not sufficiently balanced, might be transmitting extra vibrations to the rear diff which may be accelerating wear on the internal bearings and shims... but a lot of people use aftermarket one-piece driveshafts and I don't often hear of accelerated rear diff bearing and side carrier shim wear being a common side effect of using a one-piece d/s.
....
I think one step to solving this issue and identifying the culprit may be to remove the custom Torsen diff from the car, take it to another highly recommended diff and driveline shop who works with Supra MKIV diffs and get them to pull off the rear cover, check everything to be well within spec (or not) and then re-seal it when/if everything is good.
Then it can be ruled out as to whether or not the issue is improper and/or excessive play in the bearings and shims or if it's actually an issue with the old Torsen LSD itself.
...
If your SC is making more than 500whp... and especially if well more than that figure... it would be a good idea to consider a Kaaz 1.5-way Quiet LSD or an OS Giken 1.5-way Super Lock as a superior upgrade. A super rare 200mm/10-bolt Torsen T-2 is stronger and more durable than the older T-1 also... (assuming you can ever find one for sale in good condition).
My T-1 Torsen is in good shape and behaves normally in my car. But I also don't drive my SC very hard and it's only seeing 350hp which is well under the safe power range for these older T-1 LSDs.
....
I think you should get that custom Torsen diff pumpkin inspected by another highly recommended shop (preferably one which is familiar with work on Supra MKIV, Lexus SC/Soarer, GS/Aristo and other Toyotas which use this style 200mm diff system) at the very least to rule out any internal issue.
My last diff builder checked all tolerances and installed all new bearings. He also checked the tolerances inside the T-1 Torsen and said that things were still in spec and that realistically with my non-track driving I could expect at least another 150k-200k out of it if not more.
I have a little initial clunk noise sometimes when I take off from a dead stop (also with an R154 5-speed transmission with an OS Giken twin-disc clutch) but other than that my Torsen makes no additional noise that I hear.
But I think that depending on total cumulative use, abuse and wear and tear if it's always been driven on very hard even a Torsen T-1 (or T-2) can eventually develop too much play in its worm and spur gears. I am not studied on how to disassemble, measure tolerances and reassemble a Torsen LSD but this is what I have been told.
However these LSDs are designed to have VERY long service lives so this kind of wear usually takes a very long time... or a lot of cumulative lifetime abuse... or a heck of a lot of power (torque) from the drive-line going into its gears.
...
Only you can say for sure how poorly your Torsen is feeling in real world use. A diff technician could inspect its internal play with the cover off. Is it doing any newly unpredictable as to behavior compared to how it used to behave?
After viewing both your videos I went over to a spare good condition 92-97 SC400 3.92:1 open diff that I have sitting around which I used in my SC300 for a short time. I checked for the play you demonstrated and it has none of it. When I last installed my rebuilt MKIV TT Auto 3.769 Torsen T-1 LSD diff it also had none of that play you demonstrated.
I cannot tell you if what you are noticing is the Torsen LSD center itself showing an issue or if it is just excessive play in the ring and pinion in your donor LS430 3.26:1 diff which the Torsen was installed into.
Another question would be whether or not you noticed any of this same play before you installed the freshly rebuilt diff pumpkin into your SC?
...
Any one piece driveshaft will transfer more oscillations through the drive-line compared to a factory two-piece driveshaft. I have retained a factory Toyota two piece driveshaft in my car but its front section was modified for my transmission application and I can say that it has been very smooth in operation with both single mass flywheels in W58 and R154 5-speed transmissions and with a twin-disc clutch with integrated flywheel in that same R154 transmission.
I am not so certain that using a single mass flywheel with your CD009 transmission would be able to cause excessive play in the rear differential all on its own.
It's *possible* that the one-piece driveshaft, if too heavy and not sufficiently balanced, might be transmitting extra vibrations to the rear diff which may be accelerating wear on the internal bearings and shims... but a lot of people use aftermarket one-piece driveshafts and I don't often hear of accelerated rear diff bearing and side carrier shim wear being a common side effect of using a one-piece d/s.
....
I think one step to solving this issue and identifying the culprit may be to remove the custom Torsen diff from the car, take it to another highly recommended diff and driveline shop who works with Supra MKIV diffs and get them to pull off the rear cover, check everything to be well within spec (or not) and then re-seal it when/if everything is good.
Then it can be ruled out as to whether or not the issue is improper and/or excessive play in the bearings and shims or if it's actually an issue with the old Torsen LSD itself.
...
If your SC is making more than 500whp... and especially if well more than that figure... it would be a good idea to consider a Kaaz 1.5-way Quiet LSD or an OS Giken 1.5-way Super Lock as a superior upgrade. A super rare 200mm/10-bolt Torsen T-2 is stronger and more durable than the older T-1 also... (assuming you can ever find one for sale in good condition).
My T-1 Torsen is in good shape and behaves normally in my car. But I also don't drive my SC very hard and it's only seeing 350hp which is well under the safe power range for these older T-1 LSDs.
....
I think you should get that custom Torsen diff pumpkin inspected by another highly recommended shop (preferably one which is familiar with work on Supra MKIV, Lexus SC/Soarer, GS/Aristo and other Toyotas which use this style 200mm diff system) at the very least to rule out any internal issue.
The following 2 users liked this post by KahnBB6:
Bimmerbill (12-27-23),
GrantReid (12-27-23)
12-27-23, 12:55 PM
#3
Rookie
Thread Starter
Wow! Thank you KahnBB6. Your response was what I was looking for but not really what I had expected to get. After reading what you said, it became pretty clear to me there are a couple of things I overlooked that got me to the situation I am now in. My biggest error was paying $900.00 to the differential shop and never asking what they did. I asked them when I dropped it off to change the flange to the larger 200mm as well as open it and see if everything is within tolerance. I never even asked if the Torsen was measured. I never asked if they were using specs from an LS430 Open diff or SC300 torsen diff, or nothing at all other than shop knowledge and experience.
I first put the torsen in when I still had an A340e automatic. I didn't notice any issues but I never put it in neutral while driving and put it back in gear and listen for a response. I never had the aluminum drive shaft then either. With the CD009, light flywheel, aluminum driveshaft, aluminum adapter, and lack of rubber mounts the car is extremely responsive. I let off the gas and the car instantly slows down, and vice-versa.
I have my original 2 piece driveshaft with a modified front 1310 yoke assembly that I never used. I am putting it in today. I highly doubt it will solve the problem but I will know soon. I will post the follow up results.
After that, remove the torsen and put the old open diff back in.
I first put the torsen in when I still had an A340e automatic. I didn't notice any issues but I never put it in neutral while driving and put it back in gear and listen for a response. I never had the aluminum drive shaft then either. With the CD009, light flywheel, aluminum driveshaft, aluminum adapter, and lack of rubber mounts the car is extremely responsive. I let off the gas and the car instantly slows down, and vice-versa.
I have my original 2 piece driveshaft with a modified front 1310 yoke assembly that I never used. I am putting it in today. I highly doubt it will solve the problem but I will know soon. I will post the follow up results.
After that, remove the torsen and put the old open diff back in.
The following users liked this post:
KahnBB6 (12-28-23)
12-28-23, 12:35 AM
#4
^^ You're welcome! And this is a good plan of attack to begin solving your issue.
Your 1-piece driveshaft may be fine since it is using a light aluminum alloy. Usually people have issues with heavier steel driveshafts. Nonetheless 2-piece OEM driveshaft systems technically do absorb the most oscillations and harmonics with the the center bearing and joint. SC/Soarer/MKIV factory driveshafts are known to be very strong... good to up to 1,000whp at least.
Also no SC300 ever came with a Torsen LSD from the factory. No U.S. SC400 ever came with a factory Torsen LSD either. For a few model years in Canada only some SC400 trim levels had it as a factory option while the SC400 was on sale there.
Your Torsen most certainly came from a 1993-1998 Supra TT Automatic or a 1993-1998 Supra Base Naturally Aspirated model (a rare option for 93-96 Supra MKIV NA's, standard for 97-98 Supra MKIV NA's, standard for 93-96 Supra TT Autos and optional for 97-98 Supra TT Autos). Supra MKIV 6-speed Getrag cars got their own T-1 Torsen LSD standard but in the larger 12-bolt / 220mm size you can't use in the other 200m diffs.
So you would want to find and download the Supra MKIV TSRM sections for the driveline and look there for any adjustment information.
The standard factory manual procedure to install, measure and properly side carrier shim the SC300, SC400, Z30 Soarer, GS300/400, SC430 or Supra MKIV 200mm diffs are all the same. It should also be the same for that LS430 rear diff.
Setting up one of these diffs isn't overly complicated but it is tedious and requires precision. All the specs and tolerances have to be right. 200mm diff rebuild kits are available from Driftmotion using pretty much all OEM Toyota parts. The only thing it doesn't come with is the OEM Toyota side carrier shims.
For those you have to measure the ones already in the diff being rebuilt and if either side is out of the factory tolerance range you measure the difference that you need to bring each side back into spec and then refer to the TSRM where a chart shows you which specific shim thickness lines up to a specific Toyota part number. Then you order that specific part number from Toyota and finish the diff rebuild once you (or rather your diff builder) have/has it in hand.
Your 1-piece driveshaft may be fine since it is using a light aluminum alloy. Usually people have issues with heavier steel driveshafts. Nonetheless 2-piece OEM driveshaft systems technically do absorb the most oscillations and harmonics with the the center bearing and joint. SC/Soarer/MKIV factory driveshafts are known to be very strong... good to up to 1,000whp at least.
Also no SC300 ever came with a Torsen LSD from the factory. No U.S. SC400 ever came with a factory Torsen LSD either. For a few model years in Canada only some SC400 trim levels had it as a factory option while the SC400 was on sale there.
Your Torsen most certainly came from a 1993-1998 Supra TT Automatic or a 1993-1998 Supra Base Naturally Aspirated model (a rare option for 93-96 Supra MKIV NA's, standard for 97-98 Supra MKIV NA's, standard for 93-96 Supra TT Autos and optional for 97-98 Supra TT Autos). Supra MKIV 6-speed Getrag cars got their own T-1 Torsen LSD standard but in the larger 12-bolt / 220mm size you can't use in the other 200m diffs.
So you would want to find and download the Supra MKIV TSRM sections for the driveline and look there for any adjustment information.
The standard factory manual procedure to install, measure and properly side carrier shim the SC300, SC400, Z30 Soarer, GS300/400, SC430 or Supra MKIV 200mm diffs are all the same. It should also be the same for that LS430 rear diff.
Setting up one of these diffs isn't overly complicated but it is tedious and requires precision. All the specs and tolerances have to be right. 200mm diff rebuild kits are available from Driftmotion using pretty much all OEM Toyota parts. The only thing it doesn't come with is the OEM Toyota side carrier shims.
For those you have to measure the ones already in the diff being rebuilt and if either side is out of the factory tolerance range you measure the difference that you need to bring each side back into spec and then refer to the TSRM where a chart shows you which specific shim thickness lines up to a specific Toyota part number. Then you order that specific part number from Toyota and finish the diff rebuild once you (or rather your diff builder) have/has it in hand.
12-30-23, 10:50 PM
#5
Rookie
Thread Starter
Thanks again for your help. I have been so upset with the noises for the past year since putting the CD009 transmission in that I was ready to quit working on my car and get rid of it. Well, as it turns out, it was not the Torsen. I removed the aluminum driveshaft and aluminum adapter and put the old 2 piece driveshaft with a modified front yoke back in (Also required changing the 200 mm flange back to the smaller one. I used the OEM Giubo adapter. My problems are finally gone. Smooth, not jerky, no klunking. I suppose it was too modified for me the way it was. Metal on metal adapter, and as you mentioned, minimal NVH (Vibrations, etc.) with a 2 piece. Personally I think it was the lack of a flexdisc adapter at the rear of the driveshaft that was making everything so harsh not the driveshaft itself.
In case you need it, I now also have a 95? Supra MKIV digital repair manual if you need a copy.
In case you need it, I now also have a 95? Supra MKIV digital repair manual if you need a copy.
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KahnBB6 (12-31-23)
12-31-23, 05:32 AM
#6
I'm glad you were able to solve it that easily!! Congratulations!! I hope you'll be able to enjoy the car again now 
I'm not against high quality 1-piece lightweight driveshafts which are finely balanced but when I planned my build I felt that retaining the vibration and harmonic absorbing features of the OEM two-piece design would be a safe bet. With a new center bearing and new donut/guibo rubber isolator at the rear diff of course.
Lacking a rubber or urethane flexdisc against your differential would definitely transmit a lot of unwanted NVH and vibration at different shaft rotational speeds that you don't get with the factory driveshaft system.
As for the 1995 Supra main TSRM, thank you for your offer! But as it happens I already have a copy plus the 1995 and 1997 Supra electrical TSRMs. Essential literature if you own one of these cars with modifications.
I'm not against high quality 1-piece lightweight driveshafts which are finely balanced but when I planned my build I felt that retaining the vibration and harmonic absorbing features of the OEM two-piece design would be a safe bet. With a new center bearing and new donut/guibo rubber isolator at the rear diff of course.
Lacking a rubber or urethane flexdisc against your differential would definitely transmit a lot of unwanted NVH and vibration at different shaft rotational speeds that you don't get with the factory driveshaft system.
As for the 1995 Supra main TSRM, thank you for your offer! But as it happens I already have a copy plus the 1995 and 1997 Supra electrical TSRMs. Essential literature if you own one of these cars with modifications.
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