V-Spec Diff Swap 4Wd Problem

[Aggroman]

Paul had a similar problem and it just wanted the bottle in the boot to be topped up. though im sure yours is at the right marker

[Aggroman]

http://www.sau.com.au/forums/topic/301753-r33gtr-v-spec-attesa-help/

for some reading on fault codes, could be TPS issue also, man f**k these attesa problems

[Pezhead]

Yup, mine is topped up. Was just reading on the UK forum that the activator solenoid can get stuck so going to try taking that off but it requires me to drain the whole system. So will have to go get more ATF tomorrow to top it all back up.

[Piggaz]

For what it's worth, when I put my quaife front in my rear diff totally had a shit. Single peggers... Commodore owners would have been jealous for sure.

It seems to be that as soon as you put a real diff and ditch the v spec junk, the whole system has a heart attack.

[Pezhead]

Did you manage to get it sorted out? Was the computer fritzing out and throwing 4wd/ALSD/ABS errors?

Seems my system really pressurises. I primed it and the system bled like 150ml out with the engine off.

Tomorrow I'm going to get some thicker gasket material. The actuator gasket is pretty compressed and actuates the clutch pack on the last 1/4 turn of the bolts. I did try to squeeze the hydrolic back but it was firmly seated.

I'm going to have to chase down why the system is pressurizing so much and not releasing the pressure. Clearly that is a problem.

[Piggaz]

I did.

I sorted it by putting a real diff in the rear. The fromt to rear /4WD always worked properly. What didn't was the rear diff went spastic as the v spec doesn't just push torque front front to rear, it also does left and right wheels.

[XKLABA]

ditch front shaft, become a real man... problem solved?

on a serious note.. it could be your Ruzic controller thing?

This, I set mine to a higher setting for the drags and the 4WD locked on until I turned it off, I turned the controller down before turning it off

[XKLABA]

How did you go with this Eric?

Sorted yet, what diff did you get to replace the A-LSD ?

[Pezhead]

I had a fiddle with it over the weekend. Error codes 7 and 8 indicating left and right ABS sensors. That points back to the rear end swap. But they used my sensors in the new center. They said they counted the number of teeth on the ABS cog and it was the same. One thing I found is that the old teeth were about 0.5mm wider than these.

[XKLABA]

Can you take a pic for me, I think I know what it is, I found it when I did mine last weekend and had to order new sensors

Just waiting for them to get here to confirm

[Pezhead]

Really? weird. Will take a pic when I get a chance.

So did you change your diff out? Did you have the same problem?

Another weird symptom on mine is that the 4wd is on all the time. The transfer actuator is on even when the car isn't on. Fronts and rears move together already active.

[XKLABA]

Try disconnecting the rear ABS sensors

Yeah, just had my spare 32 diff rebuilt/tightened and I fitted it last weekend, I didn't even bother putting the ABS sensors in as I could see they wouldn't work properly and the 32 ones are completely different

[XKLABA]

Ok so the sensors came in today and it works perfectly

The issue I found is the A-LSD ABS sensor locator mounts vertically where the non A-LSD locator mounts horizontally which means it turns the sensor 90deg meaning the pick up in the sensor would be reading two teeth at a time and the tooth wheel is running sideways across the sensor

You will need to get the non V-Spec sensors, I ordered the R34 GT-t sensors

[Pezhead]

Great Help! I will get on that. Thanks.

[XKLABA]

Disconnect the sensors to confirm its them, disconnected you should have three lights on dash, ABS - 4WD - A-LSD and the 4WD shouldn't be working at all

The plug is at the back on top of the subframe, 4 pin plug with the lines from plug to sensors in a two by two formation

I still don't understand why your system is running constantly even with car off

[R31Nismoid]

Also to note the half shafts are different lengths from v-spec to non-vspec. Most people get a R33 GTR diff and shafts - then just bolt it in.

So just something else to remember/think about.

I'm not sure on a sensor change though? I cant recall mine being altered when it was done.

But as with Paul - once you put a proper diff up front, the rear A-LSD goes into total meltdown and doesn't work.

[Pezhead]

Yup changed my half shafts cause the alsd diff is so much wider.

[XKLABA]

Also the bolt thread are in the A-LSD half shafts where the non are in the CV

Most people would just put the diff in with the sensors that came with it so it probably hasn't been an issue yet

Yeah my A-LSD stopped working once I put the LSD up front, which I found out at SMSP-S last year

[nick_7g]

So if I want to install a new front ATB diff (e.g. quaife) - I need to find a complete rear diff housing, shafts and sensors off a non-Vspec (R33 or R34 GTR) to put an ATB diff in the rear also? Otherwise it doesn't play nice with the front done alone. What issues apply to ECUs? I'm running a Haltech.

[XKLABA]

Yeah basically, for some reason when a LSD is put up front the rear A-LSD stops working, very strange but that seems the case

R33/34 non V-Spec diff and CVs is best way to do it, try to find a diff that has the sensors already attached and the closest to your model as possible so the plug is the same, for a R34 you could most likely use a GT-t diff if your are going to change the center anyway and reuse your gears