4200/GP/QP Transmission and Ancillaries

[CatmanV2]

Yes, it was making a change. Sorry just had my wisdom teeth pulled a few hours ago and life is somewhat more confusing than usual right now.

Oh god yes. I remember that.....


....kind of

C

 

[Mr S]

Check all the bushes and mounts, something that noisy could well be external not internal.

 

[safrane]

Far noisier than my GS (and before Adam says that because it never gets used, let alone change a gear) which I drove on Saturday inside an aircraft hanger.

 

[spn]

I agree that is what it sounds like, but you made think when you said that 'well that's a control problem'. When I hook up my Launch X431 I get two options for the TCU computer, and mine works with the first version and not the second. I thought that this seemed strange as my car is a 2007. I wonder if the TCU has been swapped out with one from an earlier car? Does anyone know if this is even a thing?

Anyone know how to identify specific TCUs, or a list of software versions?

Assuming everything is ok with the clutch and release bearing, I wouldn't worry too much about the value. I have a Texa and I'm not convinced that it reports the values correctly (it over read IIRC so a ). After I changed my clutch, I spent a while adjusting the PIS point and it's now pretty good ,depending upon the revs and load some changes up and down are unnoticeable.

What I did was adjust the car with the engine on to find the bite point and then back off by 0.1 or 0.2 mm. After repeating that a few times as the clutch bedded in, it's pretty good.

Cheers,

Simon

 

[lambertius]

What was the gearbox parameter called you used to monitor the bite point?

 

[lambertius]

So I decided to pull my boroscope out and have a look at the model on the TCU.

I was expecting to see something like this...



What I found was:







That number above the barcode is 52KN2K51H

I know a lot of parts are interchangeable but I feel that having Selespeed and no reference to the Maserati isn't quite right...

 

[lambertius]

So I went and had a look at an 05 Gransport in the area, I hooked up my scan tool and was able to access the 'second version' with the scanner.

So hopefully someone with a bit more knowledge on the matter can confirm or deny; but it looks to me like my TCU was replaced with an Alfa version at some point, which was had the Maserati software installed?

 

[CatmanV2]

What was the gearbox parameter called you used to monitor the bite point?

When mine was done, it was the output shaft revs

C

 

[Mr S]

As the Selespeed pump is a replacement part, I don't see why having the TCU from the same car is a huge issue providing the software is correctly calibrated and set. Could be wrong here though....

 

[lambertius]

As the Selespeed pump is a replacement part, I don't see why having the TCU from the same car is a huge issue providing the software is correctly calibrated and set. Could be wrong here though....

That is the question... The only thing that makes me think its not right is that my scantool talks to it differently than it does the other Gransport I hooked up to. I spoke to a wrecker today, they'll send me out another TCU to test against.

If anyone can get a look at theirs, it would be super helpful!

 

[Mr S]

Wont get a chance to look this weekend, but let me know where it is, and il have a poke around when possible

 

[lambertius]

Much obliged.

https://www.eurospares.co.uk/parts/...e-trunk-bonnet-sensor-and-control-units-28242

Item number 1. Its in the right hand side above the battery, and behind two relays. The label is written on the TCU facing the outside of the car, so if you can get a camera in there or a an ebay boroscope you can read the label without removing anything, otherwise its a bit of a pain.

 

[Zep]

https://www.sportsmaserati.com/index.php?threads/4200-early-vs-late-gerabox.14330/post-320564

 

[lambertius]

Thanks Zep!

So my software is:



The much more comfortable 05 GS uses the below and different hardware for the TCU:



I've since discovered that if I 'drive it like a manual' easing off on throttle when pulling the shift paddle that I can fully eliminate harsh change. It seems to me very strange that Maserati wouldn't have just implemented that behaviour since it is a drive by wire system, but then the did put plastic lenses over the headlights...

So other than the weird way that my scantool is interacting with my hardware, it may just be a software version difference. I am trying to find another Gransport in the area to compare against and will not rest until I have reached a satisfactory conclusion!

 

[Zep]

If you spend too much time wondering why Maserati did or didn’t do something you will end up in a room with rubber wall paper.

You have the latest version, rumoured to be the “softest” gear change, it won’t get any better than that. The smart money here is on the PIS not being correct or the gearbox mount being u/s exacerbating the driveline shunt when you change. Or both.

If there was broken sensor or such like it would, in my view, simply fail to proceed.

 

[conaero]

What gear oil are you running?

Off the shelf supposed comparable oils give issues with the diff clutches.

Sometimes additives/modifiers remedy these noise issues. Look up Redline gear oil modifier but be careful with it too much will trash your gearbox.

I would drop that first and use a high end Motul gear oil as it’s the cheapest and simplest route first.

Then I would look at play in the gearbox mounts/half shafts/torque tube.

The click click (2 noises) sounds like issues in the actuator/gear selector area. When you change gear, the actuator makes two movements, exit gear to neutral, neutral to selected gear.

Maybe the pin in your actuator is broken/worn.

 

[conaero]

I’ve just listen to the video again and my suspicion is in the actuator area.

Is your actuator your original one or did it come with the replacement gearbox?

 

[mjheathcote]

The same transmission ecu hardware was used across various models and also Ferrari, and can be flashed according.
Ferrari owners even buying our Maserati transmission ecu's and reflashing them, as an upgrade.
The ecu you have has a date of 05.01.07, very late, does this correspond to the year of your car?
If not, an alfa selepeed ecu may well have been fitted later, still with the alfa gear mapping? Edit:noticed you have the latest firmware.
This can be reflashed with the last GS mapping though.
What is the scan tool you are using on an android tablet?

 

[philw696]

Looks like Launch diagnostic tablet to me Mike.

 

[lambertius]

If you spend too much time wondering why Maserati did or didn’t do something you will end up in a room with rubber wall paper.

You have the latest version, rumoured to be the “softest” gear change, it won’t get any better than that. The smart money here is on the PIS not being correct or the gearbox mount being u/s exacerbating the driveline shunt when you change. Or both.

If there was broken sensor or such like it would, in my view, simply fail to proceed.

I'm inclined to agree, but unfortunately the mounts are the easiest item to inspect and clear from the checklist. I will say some of the sounds are coming from the bad ball joints but they aren't what you can hear in the video. I've also driven a 'smoother' Gransport with older software, so I do think that there is more going on with this particular car. I am still trying to find another car to drive in Perth just so I have something more to compare against. A few friends across the globe are assisting in my quest to see if we can replicate the driving style on other cars to work out if its a defect or a characteristic. If its just a matter of driving the car in a particular way I can live with that, but if there is more to chase down I'm also okay with that. Either way I need a baseline to compare against!

What gear oil are you running?

Off the shelf supposed comparable oils give issues with the diff clutches.

Sometimes additives/modifiers remedy these noise issues. Look up Redline gear oil modifier but be careful with it too much will trash your gearbox.

I would drop that first and use a high end Motul gear oil as it’s the cheapest and simplest route first.

Then I would look at play in the gearbox mounts/half shafts/torque tube.

The click click (2 noises) sounds like issues in the actuator/gear selector area. When you change gear, the actuator makes two movements, exit gear to neutral, neutral to selected gear.

Maybe the pin in your actuator is broken/worn.

This transmission was a significant improvement over what was in the car when I bought it. I finally got a chance to speak with the guy who did the labour on it for me, and there was considerable metal debris in the older one - no evidence in the service history of the gear oil having ever been changed, similarly with the hydraulic lines. I was originally trying to look for the Red Line GL-5 Gear Oil NS, but wasn't able to source it locally so went with Penrite Pro Gear. I based the selection off of the viscosity characteristics in the data sheets, with the Pro Gear being the closest OEM specification that I could find. For the same reason Liqui Molly 1127 is what is being run as the CHF.

I'll go over the half shafts and torque tube in more detail. I'll get it running off the ground and do some inspections under the car that way.

The actuators are original, but I do have a full set of hydraulics on the way (backups). I originally tried to swap the whole transmission complete, but importing duties and port requirements were just going to make things harder than necessary so doing things in steps.

The actuators themselves operate reliably and sound the same as other cars I've played around with. I get 42bar as the system pressure. I made a video showing a self learn on my car. On other Gransports I can select the second version of the TCU, on mine I can only select the first.

The same transmission ecu hardware was used across various models and also Ferrari, and can be flashed according.
Ferrari owners even buying our Maserati transmission ecu's and reflashing them, as an upgrade.
The ecu you have has a date of 05.01.07, very late, does this correspond to the year of your car?
If not, an alfa selepeed ecu may well have been fitted later, still with the alfa gear mapping? Edit:noticed you have the latest firmware.
This can be reflashed with the last GS mapping though.
What is the scan tool you are using on an android tablet?

The date corresponds to the car, and looking through the service history TCU swaps were part of the diagnostics for this vehicle before - so others have found the operation of this transmission to be unusual. The Scan tool is in the video link above, a Launch X431 Pro Mini.