Attention GTR and GTS4 owners

[RazorGTR]

Something that does come up slow on us and thought I would share my misfortunes with you.

I don't normally give my GTR a whole lot of stick but decided to take it down to the strip and see what the old tart will do. Well after launching time and time again sideways, I thought it was the tyres that were bad and left it at that.

Over the weekend I noticed that under firm acceleration to hard acceleration I was only getting @ 10% front wheel torque on the torque split gauge. Odd I thought so I tried a hard launch of 7,800 rpm and left over 25 meters of rubber on the ground. All from the rear and only saw 12% on the gauge. It should have been over 35%. So a quick trip to my favourite tuning house who has a 4wd dyno my fears were confirmed. The clutch packs in the transfer case are shot.

I am looking at nearly a $2,000 NZD repair bill. That is providing that nothing else is wrong. The parts alone are going to be over $1,100 with GST or tax.

Keep an eye on your gauge fella's as it is a tell tailed sign of expensive times to come

[SkylineUSA]

Sorry, to hear about that Razor.

Thanks for the heads up.

[racingbreed20]

Now I dont feel so bad about my misshap...Hope things go well.

[RazorGTR]

After some lengthy consulting and digging the original problem looks to have been an electronic fault. One that the ECU would not know thus not giving me a warning light about it.

We drew this because on the way to the shop after work under a hard acceleration and shift from first to second "um a bit of anger doh" the 4wd system reacted as it should with a 40% reading on the torque split gauge. As I pulled into the driveway, which is a steep incline I was getting surging from the car. A quick glance at the instruments and the torque split gauge needle was bouncing like a ball from 0 to 10% at only 10 kms. This means it can be originating from the middle G-force sensor being either faulty or a bad connection. Either way it is not mechanical.

The original assesment of a blown clutch pack in the transfer case may not be as bad as thought. The clutchs are worn but they may not need replacing, YET.

I will keep you up to date on what we find out.

[RazorGTR]

Well got the car back today. It is work a lot better but not perfect. It was the G-force Sensor or should I say a connection. It has however done a bit of damage to the clutch packs. How much not sure as they are working but a bit slow to react.
In the long haul I will have to eventually replace them or the trasfercase. Not sure when that will happen but it will one day.

It pays to watch that gauge if you are getting too much r/w spin and little torque steer.

[R33]

Razor, sorry to hear about that misfortune. But you have brought up a very interesting point here.
I have an HKS ETC installed in my car. Some mechs and even some of you in this forum had said that the ETC might cause the clutch in the transfer case to be damaged quickly as that clutch is designed to withstand short and sudden burst of power in all 4 wheels. I have used the ETC for almost 2 years now. It is switched on at 25+75 distribution everytime I am on the track and also while driving in heavy rain. My torque distibution gauge still shows the torque being distributed. In fact while driving and the torque is distributed, I could feel the distribution as the front wheels would gain power suddenly. The clutch on my car is obviously okay. The HKS guy over here maintain that the ETC would not hurt the clutch. So I don't really know whether the ETC would one day hurt the clutch though so far nothing has happened.
Reading your story, I therefore don't think it is the clutch at all. As you found out, it is the G sensor.

[RazorGTR]

R33 it seems to be getting narrowed down to that. I will pull the center council out sometime over this weekend coming. Everytime we think we have found the problem it turns into a dead end.

The one that this is so un-normal is there are times when it just shoots up to like 40% then hangs there even when I back off the throttle then either slowly drops or suddenly drops. This is really getting annoying as hell, but it will get sorted out once and for all.

[R33]

Razor, when the gauge shoots up to say, 4O percent, did you feel the front wheels pulling? If so, then I should think that the distributor is distributing torque even when there is no need for it to do so and is that case I suppose it is something electronic. If at that time you don't feel the front wheels pulling, it means that there is actually no torque being distributed which means your gauge might be showing the wrong thing. That happens to me sometimes especially on start up in the morning...after engaging 1st gear and moving slowly, the gauge wud show 1O or even 2O percent when in fact no torque is being disributed at all. Then it will go back to normal.
Just relating my experience.

[madrose]

hay if you need any parts to swap try
like gsensor please call me on 0212979917

have a few spares

dont think you can kill the clutch pack in the tranfer case very esily
have done lots a rear wheel burnout in mine and never noticed a thing change

unlike the first autobox i had but then the auto is being used and in this case abused all the time :o)

have a few spares from a gts4

[SkylineUSA]

madrose,

I have a question, if your doing a rear wheel burn out, do you have the torque split disengaged (pulling the fuse), if so how would this effect the clutches at all? We are talking about the clutch packs in the transfer case, right? I am kind of confused, unless I am looking at it from a different point of view.

[R33]

Razor, I was reading ur posts again today and noticed that your gauge seems to show the torque going up and down in the front tyres. As u might know, my front diff gave way a couple of weeks ago and I am now replacing it. But the thing is, that was exactly how my torque gauge behaved when my diff went dead, ie it shows torque going up and down in the front tyres.
Is ur problem solved? If not, perhaps u wud want to check ur front diff.

Sky, is it possible to do burnouts in a GTR without unfusing the ATESSA?

[RazorGTR]

Yes my problem has been solved. Upon further inspections and umm a larger bill than though, it turned out to be the pump. whew as it was not a major part to replace.

The big differences in the R33 and R32 ATTESSA systems is the clutch pack clearances in the transfer case. The R32 has a larger clearance thus it is more tollerant than the R33 when the 4wd fuse is removed. Your clutch packs will heat up very quickly, also it plays hell on clutch packs in your front diff.

A mate of mine destroyed his while getting it tuned, well the tuning place did it. It was the first R33 GTR they ever tuned and cost them a bit more money than the tuning job to fix his car. He wound up with only rwd but it was sorted. For you car if you wish to compete in a burnout comp or something like that it is best to remove the front drive shaft that way you do not over heat these parts.

[SkylineUSA]

is it possible to do burnouts in a GTR without unfusing the ATESSA?

Well, yes. Its just a little harder

Razor,

In a clutch system, does it always make contact? I was under the impression that the clutch packs only made contact when needed? Hence, my thinking that when you pull the fuse.

[RazorGTR]

I used to think that also, and would have stood on my soap box preaching so. That is until I started digging deeper into it and talking with the people who race and work on these cars.

They actually are in slight contact on the R33 at all times, though not like the EVO or Subbie. From what I have gathered Nissan had redesigned it that way when they went to the R33 in order to give much better traction control.
Bare in mind on the R32 the sampling rate of the ATTESSA system is 100 times a sec. While it would appear fast in fact in today's technology it is slow. The R33 Vspec is 1000 times a second and thus reacts 10x quicker to lost traction.

I was talking to my tuner the other day about going to the R33 GTR clutch pack transfer case system in my GTR. He is not 100% sure it is feasable, but if it is I will be looking to do that as an upgrade. I don't know about you, but mine seems a bit tail happy when pushed hard at low terminal speed out of a corner. Almost like a RWD car until the fronts kick in which seems to be a bit late for blasting hard out of a tight corner.

[SkylineUSA]

Thanks for that post.

Actually, I have never been able to swing my tail out, every time I try to do it, the darn thing just plants and goes. I am tempted to run a switch from the fuse box to disengage the 4 wheel drive, just to see how it feels.

Then again, I think I'll just leave like it is