Shinchan

To anyone who has the TRD installed on the GS: I got my car installed with TRD LSD last week. After the installation of the TRD LSD, my wife start to notice the difference.. NOt a good sign for me.. since I did not tell her what I did to the car.

Anyway..I start to notice this problem: During the morning, when I make turn from dead stop, the car feels like the trac control comes one.. but there was no trac light ont he dash board... it feels like wheels or gear are slipping???? I turn off the VSC and it does the same thing from dead stop doing a turn. BUT FROM DEAD STOP TO ACCELERATE (VSC ON OR OFF) THE CAR FEELS FINE. This only happen during the turning of the car in low speed... Don't tell me to keep my foot light on gas driving off from home.. because I am.. light on gas.. same as my wife...

Anyone has any similar result or this was due to a bad installation that some gear or bearing in diff was not install correctly? Notice.. only during turning .. not if the car was accelerate straight!

GS430 GUY

Shinchan,

That doesn't sound good. You shouldn't feel anything when turning the car with the TRD LSD installed. Only time one would be able to hear or feel the LSD engaging a little is when accelerating, whether on a turn or straightaway, but really hard. If the car feels like the Trac control is coming on everytime you turn, regardless of acceleration, something is not right. I would have it looked at to make sure everything was installed correctly.

UTGS400

Speaking of the TRD LSD, how much do they help GS's? Is there a noticeable difference. If you have it installed, let me know what your reaction is.

Mr Johnson

Shinchan: Can't say whether it is "normal" or not but this happened to me too. It seemed to be more pronounced the colder it was. It doesn't happen anymore and I'll list what changed between then and now.

1) Initial install used 75W90 oil rather than the recommended by TRD 85W140.
2) On first change to 85W140 there was a noticeable amount of metal on the magnetic drain plug. Not enough to really worry but enough to notice.
3) After first change the effect went down but was still noticeable.
4) After about another thousand miles of, shall I say, "enthusiastic" driving I decided to change again. Again used Royal Purple 85W140. No noticeable shavings this time.
5) After change the effect you speak of is gone.

Don't kow what did it but that's what happened for me.

UTGS400: Yes it helps a bunch on a GS.

Shinchan

Hi Mr. Johnson,

How long did you had the TRD LSD? Where did you get the Royal Purple's diff oil? 85W140?

How much Royal purple do i need? 2 bottle?

Thanks

Mr Johnson

I've had the diff about 6-9 months. I got the Royal Purple from my local Lexus Dealer, he had a great price. Yes I bought the 85W140. Correct in that it takes about 2 bottles when you drain it yourself and refill.

GSman

iTrader: (2)

I have had my TRD LSD for about 8 months and have experienced the same "slipping feeling." I thought it was normal for a clutch-type. Maybe I will try the Royal Purple.

Mr Johnson, did you use a separate LSD additive with the Royal Purple?

GS430 GUY

So all of you are getting a slipping feeling or loss of power to the car when just making a turn at very slow speeds and traction is not being broken? Very odd. Only time I ever heard & felt the LSD engage was when I purporsely broke traction or the tires actually slipped in rain & snow. Then if it was excessive the Trac Control would kick in, which happens less now with the LSD. I had a speed shop install my LSD and they put LSD additive in as well and I went back after 500 miles to get new fluid and additive put in as they recommended. I have had my LSD in now for 10 months with almost 5K miles put on it.

Mr Johnson

No, an additive is not needed with the RP.


I wouldn't call it a loss of power but it feels like the clutch is locking and unlocking. This was easiest to detect after having the car sit overnight and then cranking the steering to full-lock as you slowly drive forwards or backwards.

Are you running 75W90 or 85W140?

GS430 GUY

I have no idea what weight I am using, but I do know I have LSD additive added to the synthetic differential fluid. I'll have to check my invoice and see if it lists the weight used. I never once had the locking and unlocking as described above though, so I can't help with that, but maybe it's the fluid used when the TRD LSD was installed. Where's JacobT? He has the TRD LSD and is very knowledgeable on the LSD.

Shinchan

My master Lexus Tech call me back.. after I left them a voicemail regarding the installation of the LSD. His desc for the click feeling was: That was what the LSD was design for. LSD allows both wheel to travel at different speed. During the a 90 degree turn, the outter and inner wheel travel at different speed.. the Lexus ECU computer was not design to have both wheel travel at diff speed. It was design with OEM spec.. where both wheel travel at the same speed. At this moment, the ECU is learning how the new stuff function on the car. Tech.. I can understand what he is explaining.. kind of make sense..

What do you guys think?

Where is the best place to order RP?

Mr Johnson

The additive is a friction modifier that is typically used to keep the rear from "binding" which I think is an applicable term for what is happening to us. So that by itself could be the resolution to the issue. What's strange from my POV was that the first change of fluid to the RP, which doesn't require additive, didn't completely cure the problem but the second change did.

Shinchan: Call your installer and ask if they used the additive. I know I simply assumed mine did but.....

The ECU "learning"? I don't buy that explanation. It feels strictly like a mechanical issue with the diff.

DaveGS4

iTrader: (2)

Definitely need the friction additive, or the type of fluid that already has it built in.

The master tech that did mine didn't have any additive on hand, so he used fluid for an RX differential that has it already built in. I'll get the RP or TRD stuff next time I change it.

I haven't experienced the symptoms Shinchan is, but driving with the LSD IS different than without it, especially in the rain and around turns. Distinctly different feel and grip, takes some getting used to. I've found myself looking for empty roads and isolated parking lots to practice launches on hills and in turns just to master it.

LVgs400

I know alittle slippage is normal around slow tight turns. I wouldn't worry too much about it. Adding some friction additive would be a good idea for sure. If others have had that problem and it is going away, I wouldn't worry too much about it. I think the TRD LSD is a 2 way clutch type system, so it may just have to get broken in alittle bit. See if it does this both during slow accel and slow decel around turns.

Shinchan

I'll have to call to find out if additive is added! In the mean time, I am going to find a local store to buy RP. When Steve's TQ arrive, I'll have them put in the Torque Master Plug + Drain and refilled with RP. I hope the RP will make the problem less noticable.

You see, I did not tell my wife what I did to that car.. so.. I'll need to come up with some explanation...soon.. or change the RP.. maybe before the TQ Master.