how to improve gu auto gearbox

Only the "snow" one......Unless its hidden..mines an 03

i fitted the heavy duty valve body. cost $900 and worth every penny. tow 3 tonne with ease, especially with manual lock-up torque convertor switch. transmission shifts are super crisp,auto temps are low, fuel economy is better. for towing heavy loads I think it is a good mod.

Hi june where did you get the H D valve body off

wholesale automatics. check out the link on this first thread

I've been planning to do this resistor upgrade for about two years, and this week I'm finally getting to it.

Does anyone know how many revs you need for the torque converter to safely lock with a 1000k resistor? I think with the original resistor you need about 1800 revs.

Thanks for the GQ resistor location photos Boggy and the wiring diagram Chaz.

Wholsale autos are the best in the game with 4x4 autos. Lockup kits and valve bodies a relitivly cheap and make a bumch of difference

Finally did this, but I'm confused.

Tried a 2.2k ohm to start with thinking it could be a bit harsh. That didn't seem to be much different, so I unplugged the resistor completely and it's still not harsh on the changes except for when I manually change up under light load. It does seem to automatically hold it in the gears longer sometimes.

The box was reco'd about 20,000 K's ago, and the fluid was recently flushed with genuine Nissan ATF. It didn't slip when I tried to get it to, and often changes gears so smoothly I don't feel it.

Any ideas on why it's not much different?

I just unplugged mine today and it doesn't seem harsh really just feels good and firm much quicker through the gears I'm thinking is there any point putting in a resistor?

Cheers for the info fellas

Great info :thumbup:

i had a slight sudder going into o/d
changed oil now ok
does this line pressure mod work on 06 3lt
will it effect o/d shifting in & out on h?way {very annoying }
cheers

The "O/D shifting in and out" is probably your torque convertor locking/unlocking which is not only annoying but is also generating unnecessary heat in the trans.
This is why people fit a manual torque convertor lockup system.. as mentioned earlier in this thread.

I'm not an expert on this, but recently have been playing with my auto, and yes this can be one of the reasons people fit the manual TCC lockup. I have one and I use it alot for this same reason, but if I am driving normally at 100kph or above on open roads, then I don't really have the problem. It is normally at slightly lower speeds and undulating highways.

Basically, your TCU has a heap of settings and parameters that dictate when the TCC engages and disengages. Throttle Position, revs, speed etc. It sounds like that position is close to the conditions you are driving at on the highway.

The manual Torque Converter Clutch lockup kit will override these conditions until it is either manually unlocked, or accelerate hard etc.

I've never heard of a manual lockup that cuts out when you accelerate hard FNQGU. Is yours a known brand, or custom built?

Pretty sure it does, although I appologise if I am wrong. Might be a setting on the Compushift II that does it. I will have to try it again. There are so many settings to play with on it that it gets confusing.