I'm thinking about installing the TRD LSD in my GS430, anyone with experience doing this?

(I don't want to do the Supra 3.76, it's too low for me.)

 

You might want to read this thread:
https://www.clublexus.com/forums/sho...hlight=trd+lsd

 

I read that thread, it wasn't clear to me there was any posters that had actually installed (or paid to have installed) an LSD in the stock pumpkin. In some diffs, the LSD can be installed without changing anything on the gears (or having to own fancy measuring tools to install properly). WRT the 3.76, I don't want to install a 3.76 in my GS. I have a 3.73 gear in my Impala, with a 0.7 overdrive and 27" diameter wheels, for me the motor is reving too high @ 75mph. I do plenty of highway miles, my preference is to stay with the 3.26 gear. OTOH, I really want an LSD, esp for driving in the snow.

 

umm redgs4 got the ADS (??) lsd on his stock pumpkin, you might wanna ask him. but from what i read, the trd unit should be bolt on to the stock system, as long as all the fitting kits are good (i hope i am quoting the right words)

for the rpm? the 3.76 will be constantly about 300rpm higher in the rpm. at 80mph, instead of 2700rpm you will be going at 3000rpm with the 3.76. i don't think it's that big of a difference?

 

Actually, I almost went this route, until I found it's a royal pain in the butt and quite expensive as well. The pumpkin will have to be removed from the car, the carrier removed from the pumpkin, and then the gears and differential from the carrier. Then you'll have to find a mechanic competant in swapping gears and shimming them. The new diff and gears back into the carrier, then checked for appropriate backlash (within .10 tolerance) and then the pinion gears may need to be shimmed.

Then reassemble and put it back onto the car and cross your fingers Atleast 4hrs of labor quoted from 2 speedshops and 5 hours from a transmission shop ,although they didn't exclusively deal with Lexus/Toyota cars. Hope that helps.

 

And after that there is an extensive break in process. If you screw that up your clutches won't engage smoothly. I was doing figure 8's in the company parking lot for a week.

 

The difference between a 3.26 and a 3.76 is ~15%, 2700 becomes ~3100. It's a constant 15%, across the board.

 

I think the GS has a 3.23, not a 3.26 (not that I've done the math to figure out if its significant in the 15% calc).

 

This part I can do myself.

Around here there's shops that will do this for $200, if you bring the the pumpkin. The shop I hired to swap my Vette's gears has done several open road race cars (Silver State Classic, etc).

That's what makes life exciting!

It does, now I know the Lexus diff needs to be dropped and the gears pulled to install an LSD. I guess I'll need to call the gear guy and see if he can do a Supra/Lexus.

 

You might also check the 4x4 places, the 4 runner shares the same 8" ring gear as us and the supras, so I know many of them do a LSD swap as well. Good luck....

 

dunno, i can only trust my speedo though. how about other people?

 

I don't know about your calculations Vette Boy, but my rpm has gone up by 300 rpm at 60 - 70 MPH. Just like Rominl said.

So cruising at 60 MPH is now at 3K rpm and definitely NOT 3100 rpm.

And to second what DaveGS4 said, yes the OEM gear ratio is 3.23 not 3.26.

 

I have 3000rpm at 80mph

 

It's pretty hard to pick off 100 RPM off of the analog gauge, all I'm saying is that the engine speed picks up 15% for the gear change (ok, since the gear is a 3.23, is actually 16%). If you're seeing 3000 RPM with a 3.76, the engine speed would be 2577 with a 3.23 gear. That's 423 extra RPM, not 300.


Thanks for the info, if the stock gear was 3.23 and you change to a 3.76 then the engine speed will go up 16% across the board. It's not a constant 300RPM.

 

No sir. I disagree with your theoretical calculations. Real world experience is very obvious and I know the difference between 2700 RPM vs. 2577 RPM. The analog tach on a GS is not that "tiny" that we make a mistake like that when reading the gauge.

I also disagree how you think that we cannot tell that the analog tach is reading 3100 rpm if in fact it is reading 3000 RPM. The needle is either directly on the 3K mark or it isn't.