02S 6 speed conversion into 02J case

[antoniu200]

Hi,

I am looking into swapping the factory-installed SMF in my mk7 Golf 1.6 TDI DDYA engine, RTD MQ250 (0A4) 5-speed transmission with a DMF from the mk7 Golf with the same engine, but 6-speed manual gearbox (02S) (there is none for my model).

Reading all over the internet about this transmission, I understand the outer case is very similar between these two models, something that you confirm:

[...] an MQ250 02S, which is effectively a 0A4 5 speed with another gear added to it.

The 0A4 is just an evolution of the 02J, which is itself is a mild evolution of the older 02A that dates back to the late 80s with the first Corrados. 02A/02J/0A4 "MQ250" gearboxes are about as close to Lego interchangeability as it gets for their internal parts for a design that dates back close to 35 years at this point.

[...]

This is also interesting because it means you keep the same shift bracket, same axles, starter and the much more affordable clutch and flywheels that the 5 speeds use.

Now, my question is, does this apply the other way around: i.e. the 5-speeds get to use the higher quality clutch and flywheels from the 6-speed platform MQ250?
Has anybody here tried this (or the other way around) before?

Thanks for the advice!

 

[Matt-98AHU]

Hi,

I am looking into swapping the factory-installed SMF in my mk7 Golf 1.6 TDI DDYA engine, RTD MQ250 (0A4) 5-speed transmission with a DMF from the mk7 Golf with the same engine, but 6-speed manual gearbox (02S) (there is none for my model).

Reading all over the internet about this transmission, I understand the outer case is very similar between these two models, something that you confirm:


Now, my question is, does this apply the other way around: i.e. the 5-speeds get to use the higher quality clutch and flywheels from the 6-speed platform MQ250?
Has anybody here tried this (or the other way around) before?

Thanks for the advice!

Clutches are interchangeable for MQ250 family transmissions. The exceptions you have to note are using Mk5 or newer clutch and matching flywheels on earlier (02J or older) transmissions is probably a no-go. But you can use the older clutch and flywheels on the 0A4 and 02S no problem.

0A4 and 02S have an additional 4.5 mm offset to their bellhousing where it mates to the engine. Later clutch and flywheel designs for them typically have a little extra offset to more or less match that. So, if you use a Mk5 clutch and flywheel with a 02J, you might end up with the pressure plate rubbing the inside of the bellhousing, the casting that holds the pinion bearing outer race in the bellhousing...

But everyone seems to have no problem using the older clutch and flywheels on the newer transmissions, the hydraulics seem to adjust and compensate for having to reach that little bit further no problem.

I don't know if 02S clutches in your market are any real upgrade over 0A4 versions, but they do interchange. There probably is numerous different variations for both transmissions in your market I imagine.

The 2.5L 5 cylinder engines here in the U.S. use the same crankshaft bolt pattern as the 4 cylinders, and later versions came with a single mass flywheel if you're wanting to do away with the eventually problematic dual mass...

Or more readily available is using the single mass from the 02A equipped Mk3/B4 Passat era TDIs and either a Sachs K70038-01 clutch kit or LuK 17-034 to go with it. Or a modified South Bend clutch assembly that uses one of those as its starting point.

 

[antoniu200]

Clutches are interchangeable for MQ250 family transmissions. The exceptions you have to note are using Mk5 or newer clutch and matching flywheels on earlier (02J or older) transmissions is probably a no-go. But you can use the older clutch and flywheels on the 0A4 and 02S no problem.

0A4 and 02S have an additional 4.5 mm offset to their bellhousing where it mates to the engine. Later clutch and flywheel designs for them typically have a little extra offset to more or less match that. So, if you use a Mk5 clutch and flywheel with a 02J, you might end up with the pressure plate rubbing the inside of the bellhousing, the casting that holds the pinion bearing outer race in the bellhousing...

But everyone seems to have no problem using the older clutch and flywheels on the newer transmissions, the hydraulics seem to adjust and compensate for having to reach that little bit further no problem.

Music to my ears... Thanks!
I am going to talk to my mechanic and schedule a day for dropping the car over.

I don't know if 02S clutches in your market are any real upgrade over 0A4 versions, but they do interchange. There probably is numerous different variations for both transmissions in your market I imagine.

The 2.5L 5 cylinder engines here in the U.S. use the same crankshaft bolt pattern as the 4 cylinders, and later versions came with a single mass flywheel if you're wanting to do away with the eventually problematic dual mass...

I am surprised you find the DMF problematic: my father has a 2014 B7 with 200,000 KM on board (~125k miles), still running the factory DMF, clutch and everything, with absolutely no problems.
My Golf VII 1.6 TDI comes equipped with a SMF from the factory, which makes it a B to handle during busy traffic, especially since the throttle pedal has a deadzone that causes juddering when leaving / entering it. Quick shifting is usually impossible, except for 3->4, 4->5; and general downshifting is also a pain, since it's either very slow, or juddery. Really looking forward to replacing it with a DMF.

I am going to update my threads with this information you provided me.
Big thanks again!

 

[Matt-98AHU]

Music to my ears... Thanks!
I am going to talk to my mechanic and schedule a day for dropping the car over.



I am surprised you find the DMF problematic: my father has a 2014 B7 with 200,000 KM on board (~125k miles), still running the factory DMF, clutch and everything, with absolutely no problems.
My Golf VII 1.6 TDI comes equipped with a SMF from the factory, which makes it a B to handle during busy traffic, especially since the throttle pedal has a deadzone that causes juddering when leaving / entering it. Quick shifting is usually impossible, except for 3->4, 4->5; and general downshifting is also a pain, since it's either very slow, or juddery. Really looking forward to replacing it with a DMF.

I am going to update my threads with this information you provided me.
Big thanks again!

DMFs are typically good for about 150-200k miles, depending on how its driven and which specific one it is.

I do like the LuK 17-050 kit for cars that aren't highly modified. They hold 270 ft-lbs without slipping. I did have a modified 17-050 kit that had more aggressive friction material on it to hold more power, the flywheel did not put up with the 290-300 ft-lbs my engine setup was putting out. The shudder from the flywheel under load in higher gears was really bad.

For cars under 240 ft-lbs of torque, it doesn't seem to be an issue. But as you get over that mark, those flywheels do not put up with it well.

The 02Q flywheels hold upto those levels of power much better, but you're not going to be able to use those with a 02S or other MQ250...

The G60/028 TDI single mass flywheel with a LuK 17-034 or Sachs K70038-01 is really nice to drive with a new flywheel. Super light pedal effort, smooth engagement. Only a little feedback that lets you know where the grab point is, don't make horrible rattle noises like the popular "VR6" kit (K70038-02, or LuK 17-036). I like them. They've been my go-to for MQ250 clutches for many many years.

 

[Correa]

Hi,

I have a question about gear box mount
my project is to swap a AWG (mk4 2.0 petrol convertible) engine with 02S gearbox in a MK3 chassis (in fact it is a mk2 but all subframe and drive train are from mk3)
I taught I could use a 02A engine mount, but it doesn't feat

what mount should I use?