420R in New York

[KnifeySpoony]

1 hour ago, CBuff said:

Or maybe  pick some good roads and do a soft street drive in them. 

Hoosiers on the street?

 

[pethier]

 13" Yokohama A052 at KitCarDirect
 

https://www.kitcardirect.co.uk/products/yokohama-advan-a052-tyre?variant=53701139235159

 

Both 205 and 195. I don't see these on Tire Rack.

[CBuff]

My 2023 420r with 3.91 rear end and 5 speed (11k miles ). The lsd has started to make a lot of noise. Slow full lock turns sound like it’s coming apart.  Pre load is still at 38lbs and the wheel turn in the same direction when raised. 
 

the sound makes me think I am living on borrowed time. And I can’t stand the clanking grinding noise anyway. 
 

spoke with Steve perks at Tracsport. He is sourcing me a new 3.64 diff from caterham and dropping in a Tracsport lsd and sending me the entire unit. We will see if I have the skills to replace the unit.  Money sent late last week. Will see when it arrives. 

[KnifeySpoony]

2 minutes ago, CBuff said:

 

My 2023 420r with 3.91 rear end and 5 speed (11k miles ). The lsd has started to make a lot of noise. Slow full lock turns sound like it’s coming apart.  Pre load is still at 38lbs and the wheel turn in the same direction when raised. 

TADTS

[CBuff]

It never did it before. Makes me sad. 
 

 

[CBuff]

I recieved my new diff with the transport lsd in late August. Will likely attempt the install over the winter 

 

[KnifeySpoony]

Diff install was a royal cunt for my build. I wish you godspeed. 

[Ian7]

On 7/6/2026 at 7:56 PM, CBuff said:

 

The lsd has started to make a lot of noise. Slow full lock turns sound like it’s coming apart.  

 

In 2 years and only 11k miles? Did you drain it and see what came out?

Did you even get any oil out, never mind any metallic bits? I notice the "no oil" sticker on the new unit, any chance your original was dry? (but hard to imagine a dry diff lasting 11k miles).

[CBuff]

@Ian7 I def checked it before using it and it had some type of oil in it. I changed it out to the suggested motul 75w90 (1.3 liters). The stuff that came out was brown ish but dont know what it was like going in. I added some Redline 80301 limited slip friction modifier back in august. that helped a little. The pre load has remained steady at about 35ft lbs. Operationally it hasn't changed in performance. 

 

Since the titan LSD is bound to fail, I figured I would get the tacsport lsd and the 3.64 diff. It's def not happening until winter. Maybe get the 3.91 rebuilt and either sell it or have it as a backup.

[Croc]

18 hours ago, Ian7 said:

 

In 2 years and only 11k miles? 

 

 

I know - shockingly bad.  There are a litany of BMW/Titan diffs (BMW housing and Titan bespoke internals) failing at the 10K mile mark or even earlier.  Its definitely not a driver issue.  I just fixed a 2021 car with less than 7K miles on it - friction plates failed.  

[Ian7]

23 minutes ago, Croc said:

 

I know - shockingly bad.  There are a litany of BMW/Titan diffs (BMW housing and Titan bespoke internals) failing at the 10K mile mark or even earlier.  Its definitely not a driver issue.  I just fixed a 2021 car with less than 7K miles on it - friction plates failed.  

 

too much power going into a diff with too much internal lightness ?  :-)

 

IMHO, driving any car in what would be called a civilized manner on the street doesn't require a LSD, more trouble than they're worth unless you're on track.

(I'm gonna get flamed, I know)

[pethier]

3 hours ago, Croc said:

 

I know - shockingly bad.  There are a litany of BMW/Titan diffs (BMW housing and Titan bespoke internals) failing at the 10K mile mark or even earlier.  Its definitely not a driver issue.  I just fixed a 2021 car with less than 7K miles on it - friction plates failed.  

I hope to have more luck with the Sierra/Drexler/4.71 I'm having made up in Kent for my CSR 260.  I'll keep the Quaiffe/3.62 on the shelf in case my heirs sell the car to a big-track driver.

[pethier]

20 hours ago, CBuff said:

@Ian7 I def checked it before using it and it had some type of oil in it. I changed it out to the suggested motul 75w90 (1.3 liters). The stuff that came out was brown ish but dont know what it was like going in. I added some Redline 80301 limited slip friction modifier back in august. that helped a little. The pre load has remained steady at about 35ft lbs. Operationally it hasn't changed in performance. 

Reminds me that when I had my Europa the preload was 90 ft-pounds. Caused massive understeer in autocross events where the traction was not first-rate.  I put in a full bottle of Slick-50 ManTran and it dropped to 20. much-more drivable.  I am having the Drexler set to zero on the overrun on my CSR 260.