rorror45

I'd like to buy a RWD model with Torsen LSD. Is there an easy way to tell if a car has one? I know I can enter the vin number here https://drivers.lexus.com/lexusdrive.../vehicle-specs for factory-installed options. Does LSD show up there if the car has one?

zheka130

There is a thread about this, people said that it only became an option starting either in 2017 or 2018, on the RWD F Sport model.
Not available before then. Shame, it's always better to have on a RWD vehicle.

Knucklebus

The only positive way is to look at the differential. If you have an inspection camera, you could drain the rear diff and look through the fill and drain holes. If you see spider gears and nothing else, is an open rear end. If you see clutches, springs or anything else between the spider gears, you have some sort of traction aid. Other than that, there isn't a sure way to know.

bclexus

Jack up the rear of the car where both rear tires/wheels are off the ground and manually rotate one of the wheels to see if both wheels turn in the same direction or in opposite directions.

Knucklebus

That only works on a clutch-style differential. That doesn't work with a Torsen-style unit. They will happily turn in opposite directions with no resistance, which is the beauty of a Torsen, no chatter or jerkiness. You might be able to jack one wheel up, put it in neutral and turn the drive shaft to see if it locks up. I may try that on my Torsen-style rear diff in the near future.

bclexus

Or just do a burn out...

bclexus

Knucklebus

It is an elegant solution to the clutch-type positracs. The other great thing is no oil additives needed. My clutch-type posi will chatter if you don't put the right additive in the oil and the clutches eventually wear to the point that engagement is not as strong as might be needed to get out of a slippery spot.

I'd like to have a Torsen-style in the rear of my GS 350 AWD as an extra measure of security but with the traction control and stability nannies, it really isn't that necessary.

Interestingly enough, I don't think my wife's AWD Honda HR-V has a differential at all. I think it is strictly clutched engagement to the ring carrier per axle. With one rear wheel off the ground and the drive shaft locked in park, you can turn the rear wheel and it is clearly not attached to anything mechanically.

bclexus

Yep, GM Posi-Traction had its drawbacks back in the day. The smell of sulfur lingers in the air when you open the differential. I've replaced a few R&P with 373, 411 and 456s. Some were left sitting in the staging lane when the ring gear snapped.

Knucklebus

Ah, the good old days! I actually ran 5.13s for a short time... in my daily driver! Top speed was 90MPH at 6,000 RPM. This in the early 80s when gas was $2/gallon and it got 16MPG on a good day. Nothing could beat me between stoplights but it took 90 minutes to drive 50 miles. It still got 16MPG with 5.13s, probably because I didn't build up much wind resistance at 45MPH.

The Lexus GS is less than half the 7.6L displacement and gets slightly better than twice the MPG. Both cars weigh in at nearly 2 tons. Then again, the Lexus has 50+ years of technological improvements, the biggest being ECU controlled fuel injection and 2 extra gears.

bclexus

But the Lexus doesn't sound anywhere near as good, nor does it provide the excitement...

er34

Find an empty road, do a burn out, if you see one skid mark, you have open diff, if you see two skid marks, you have LSD.

jgscott

iTrader: (1)

Turn off Trac control, and/or do it on a semi, or wet road?

I thought it started in 2016 on the 2017 models? I know sometimes in the past Lexus has put on some cars but not others anyway. I did the burn out test and had 2 rubber marks so I thought my 2013 had it. Now I have also heard that only the F Sports with Dynamic Steering had it? But..IDK?

To add more confusion..... yes there was a limited Slip that was Not Torsen, and one that was a Torsen I found when I researched years back.

https://pressroom.lexus.com/2017-lex...gs200t-gs450h/

Now in 2019 the 2020 IS listed it specifically. Anyone seen the GS Lexus info say Torsen?

zheka130

The dealership should be able to tell you if you provide them with a vin, I would think 🤔

jgscott

iTrader: (1)

Actually now I remember asking one of the Lexus Tech about my car and both wheels spinning. He told me that I may just have something they designed called a brake actuated LSD. I was thinking about changing it out to a Torsen, because I was told the SC400 one would work and be a faster bottom end LSD if I remember correctly?

But I got to thinking that if some kinda electronic control was involved, then there was also something about having to have it gear set or aligned or something like that, and it just sounded way too much of a mess to me. lol!