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Link http://www.nagtroc.org/forums/index.php?sh...=25361&st=0

A couple of things. Is the transmission made by the crowd who made them for the Veyron? Disconnecting the traction control voids the transmission warranty? A bit rough and perhaps unsustainable if there is a manufacturing fault or the transmission is not fit for its intended purpose?

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https://www.sau.com.au/forums/topic/239115-us-transmission-failures/
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Well, the box definately has some form of torque limiting feature built into it's smarts, because all the vehicles that have had Cobb tuners etc installed, show an extra 50 to 100kw on the dyno, but run 11.2's and 11.3's just like a stock one. The gearbox is both the best and worst feature of the vehicle imo.

Love the way it works, but I can't help thinking it may hamper really big hp applications. Of course, the shift protocols wouild also require remapping if and when they get around the torque limiting, and then there's the question whether those clutches and/or internals can handle more grunt?

Interesting times coming I reckon......

My impression is that there is some serious transmission abuse going on, which with any car will eventually lead to a failure. It seems that there are a number of other make owners in the US who are seriously pissed that the R35 has received so much attention and they are doing their best to discredit the car that is taking attention away from their cars.

The various targa R35's in AU must be giving the transmission a serious workout, no failures yet are there? Good test for a transmission I'd guess.

No, plenty of geartrain noise in first gear, but it's always been in the car. We decided against using LC during the event though, as we wanted stabilty control on and you cannot have both, and the car gets away very nicely anyway.

Over a 25 klm stage the transmission oil temp didn't creep over 115 degrees that I saw, and it was just awesome all the time. No failures as yet (hopefully never!) in the geartrain, even though the car left the ground at times without any throttle lift in 2nd, 3rd, 5th and 6th.....

I'd like to know what gear that is thats stripped in that link, I'm not familiar with the 'box to know just by looking. Any ideas?

Edited by Marlin

the thing is, doing these launch-controlled starts is so much harder on the transmission than any race track driving will expose it to (super high oil temps not withstanding).

just think about the physics here- it's a 1740kg car, with wiiiiide&grippy tyres (140 treadwear rating from the factory), a super-fast response AWD system that almost instantly goes to 50:50 torque split, and an engine that makes at least 580Nm of torque at launch revs. doesn't take a real braniac to see where this is heading...

i think the problem is thus: thinking back to high-school engineering science, metals have whats called 'plastic' and 'elastic' strain limits. the 'elastic' limit is how har it can deform and return to the original shape (think of flexing a metal ruler gently), whereas the 'plastic' limit is how far the object can be deformed before it fails catastrophically; though it won't return to the original shape after the 'elastic' limit threshold is exceeded (again, think bending a ruler until a permanent crease forms)

what i think is happening with these R35's that have had gearbox failures, is that the owners that spend all day smoking everyones arse off at the traffic-light GP are taking certain teeth on the 1st gear gogs up to and past the elastic limit with every launch. eventually most, if not all, the teeth on 1st become deformed past the elastic limit, and the next time the car is launched with the cogs in the fatally weakend spot, it just lets go.

that's my theory anyway- if it wasn't the case, it'd just die the very first time you tried it.

and looking at the shots of the busted box, they really aren't small gear faces, either...

from reading the guy lost 1-3-5, so you'd assume it's 1. But maybee even the R35 has a week 3rd.

1st

the tranny obviously has a built in function where it doesn't try and select certain clutch groups if there is a drive irregularity detected

Suddenly the claims of porsche having trouble getting out of third with the gtr has merit. If u paid this much money for a car then u should be able to drive it like u stole it when u want to.They obviously made it with the weak gearbox. Nissan need to Fix the problem and look after u r clientel b 4 they send the GTR name into the toilet.

Supercar my ass!!!!!!I have become a fan of skylines in the last year or so but reading this is garbage.

As a supercar it should be able to take a licking and keep on ticking. I would be loading up with ammo and going to my dealership if they gave me this answer.

Hopefully they have the problem fixed b 4 u aussies get a hold of one. They should have disabled the ability of the LC from factory if it would void the warranty. its like getting the atomic bomb but being told that u have voided the warranty after u pressed the redbutton. BS to the max.

there american fat C#*ts remeber, 1750km car + 200kg driver + 80kg fuel+ 20kg of Maccas in the passenger seat + launch control trying to race to the hospital after realising a stroke is comming on...... super car or not ALL cars have a fault somewhere.

mabey the tranny needs to be alitle stronger but we will see what happens....

also the quote above that says in a nut shell that supercars should take a hiding and keep on going is completely shit..... yes supercars are expensive but none of them are reliable. They produce that much power that many things can and do go wrong. How many supercars do you see driving around in a month???? almost none, how many people see late model ferraries and porsches on the side of the road or on the back of a towy???? allot more than you see them driving i can assure you that....

a super car is meant to be thrashed but abuse will kill it.... and yes the launch control is the most damaging feature on this car and i rememebr reading 10 launch controlls can f**k it up completely, no one in a conventional gearbox and clutch can launch like these things do time and time agian, hell normal gearboxes can snap in minutes of heavy driving and there is nowhere near asmuch force as there is in the gtr.... still at the gtr's price range nissan should take this very serious and rectify any faults there may be.....

i remebr watching a documentary on the guy that is ferrari's official car tester in italy...... he went through a rari gear box in less than 60 seconds before the car wouldnt move forward at all, he had to take it back to the pits in reverse, the only difference with the rari and a gtr is people who buy the italian red machine are buying it in general for show of status, not for thrashing......

people buy the gtr for thrashing and performance, not really for status and looks

found the link i was talking about http://www.youtube.com/watch?v=Ux1KLSo-Mcc...feature=related

that's nothing to do with the gearbox

i think you'll find one of the a/c lines or gas canister let go

That'd suck. All I know is that this seems like it may be a manufacturing fault. What's the point of building a car with L/C if the tranny can't cope with it? Either don't include the launch control or strengthen the tranny.

It could simply be that the first batch of cars have a problem that has yet to be rectified.

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