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Hi Guys,

Well after having the transgo for about three weeks now I have to say im not impressed. In manual mode the 2>3 shift is very clunky and if i floor the car in drive regardless of what speed im going the down shift is very aggressive: like someone rear-ended you.

I have noticed several issues with my car:

1) On several occasions in D at WOT the transmission would upshift way before redline (at ~5k rpm) and the change was not crisp or fast at all...I would say even worse than the stock transmission.

2) Another example is if im doing approx 60-70km/h and i floor it in D the transmission will downshift, then upshift, then downshift again.

3) Sometimes if im in D and i floor it, it takes 2 - 3 seconds for the car to react. During the few seconds before it downshifts it just accelerates in the gear that it is currently in (5th if im just cruising).

4) In D if i floor it the transmission will SLAM into gear with a loud bang...is this normal?

I have reset the ECU by leaving the battery disconnected for about 10min. This didnt change anything.

Has anyone had the same or similar issues with their transgo? I had it installed by a well know auto transmission shop in Perth but im now wondering if it was not installed correctly.

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So much fail in this thread.

Firstly, the shift kit doesn't fix the inherent issues with the transmission controller, that is the source of all the things you are complaining about. Every time it clunks into gear you are flooring it right? but the electronic throttle hasn't opened yet... It waits till it gets the signal from the auto computer before it winds the throttle on. If the throttle had instant response you wouldn't be having issues at all.

Disconnecting the battery won't do anything, other than reset the radio.

Perhaps you should have researched before you jumped into the shift kit. Are you sure the 'specialist' used Nissan MaticJ or similar? Most just stick Dextron3 in and fluck the box, knowing you will be back for a rebuild.

Finally, stop driving in D, it's for grandma... :P

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Ahh I see.

Well I researched this extensively...mostly on the G35 forums.

Im not too worried about the hard shifts / clunking as I was expecting this. Was more curious if it was normal behavior or not.

Im not sure if they used MaticJ or Dextron3.

Haha perhaps ill have to use the "manual" mode all the time now :)

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The ecu adjusts the line pressure in the box according to the load that the ecu determines to be on the engine. More load = more pressure = quicker changes.

So regarding number 1, my bet is that you lifted off the throttle at 5k rpm, and expected it to change, which it won't. Another thing is that the pressure in the GB doesn't go away instantly. So if using manual, you lift off the throttle and change up, your likely to get a clonk.

All other things I think Scotty covered well.

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The ecu adjusts the line pressure in the box according to the load that the ecu determines to be on the engine. More load = more pressure = quicker changes.

So regarding number 1, my bet is that you lifted off the throttle at 5k rpm, and expected it to change, which it won't. Another thing is that the pressure in the GB doesn't go away instantly. So if using manual, you lift off the throttle and change up, your likely to get a clonk.

All other things I think Scotty covered well.

Regarding point 1. I was at WOT when it shifted at 5k rpm..I was expecting it to shift at the normal ~6.6k rpm.

Also my second point. The transmission never did this before at 60-70 kmh it would always downshift into 2nd. This has only started to do this for about a week.

Im assuming this is related to the transmission controller and not the actual VB?

Thanks for the info so far guys!

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The transmission is always trying to be in 5th, for the fuel savings. When you boot it, it will kick down, but it has to drop 3 or 4 gears which takes time. Meanwhile the throttle hasn't opened yet but the line pressure is at it's highest due to the TPS showing full throttle.

Thank Mr Nissan for such a crappy throttle response, and Jatco for an even crappier auto controller that can't be programmed.

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If you drop the pan and dump the fluid you will change around half of it. You may need to do that a few times to get rid of most of it, or just power flush it like Alex mentioned. If they won't do it, just do it yourself.

You can use Nissan matic J or some of us are using the Nulon synthetic trans fluid which works well, and is a Matic J replacement. (Penrite do a semi synth which is Matic J compatible too, but I haven't used it yet on one of my customers RE5's.) They are a little thicker than the dextron3, not sure if that is why it works better...

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  • 2 weeks later...
  • 2 weeks later...

Hey,

I have not had a chance to swap the fluid out yet. Will be getting it done in the next few weeks or so but from what the auto shops tell me it probably wont change the way it shifts.

Seem like my car has settled down a bit now (I assume from the TCU learning how I drive?). The only thing i don't like is the 2>3 shift (still very clunky regardless of how fast or slow i accelerate) and downshift to 2/3 from 5th. I can live with these things tho as the gear changes are a lot crisper.

It would be interesting to meet up with some people in Perth who have the transgo and see how their car drives!

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I can't believe you haven't changed it to be honest.

f**k what auto shops are saying. Those guys don't know shit, and couldn't recommend you the right product to save their lives. Do you know that running the wrong oil may fark your gearbox? I suggest you get onto it quick, unless you have the coin to rebuild the gearbox when it goes pop. Get some balls, go back to the place that installed it and DEMAND that they use the right grade fluid, and flush it completely.

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Getting that Dextron III out of your car should be an immediate priority!

Dextron III = Nissan Matic D which is specified NOT TO BE USED in the RE5. Hell, it even says on the dipstick "Matic J ONLY" (or something along those lines).

Dextron III will aid your RE5 transmission in a very early demise.

Figure it this way, drop it or start factoring in for a $5k rebuild.

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I have only done approx 1000kms with the current fluid so I figured it would be OK for a few weeks. Anyway im having the transmission flushed with Matic J on Monday at another shop as the place that did the VB insist that the fluid they used is compatible with Matic J and will only flush it at a cost...so ill just take my business somewhere else.

I have been quoted $300 - $500 for the flush as apparently Matic J is expensive but id rather that than face several thousand down the track.

If the new fluid has any effect on the way the AT shifts ill let you know!

Cheers for the help so far guys.

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