2006 brm 5speed GQQ swap to mk4 5speed

Juls2714

Member
Joined
Sep 17, 2017
Location
Pittsburgh
TDI
06 brm 5speed
my differential blew apart and was wanting to swap to the mk4 5speed. i have no idea what all i will need to change out to do the swap. planning on doing clutch while its out debating getting rid of the dual mass flywheel. any input would be greatly appreciated. car only has 100k miles with no cam wear present. i just had the timing belt done really wanting to keep the car and have it last. eventually want a tune and some minor bolt on upgrades.
 

Bob S.

Top Post Dawg
Joined
Aug 17, 2006
Location
Central MD.
TDI
A B4V, some ALHs & BRMs
I have wondered if the Mk IV tai transmission would work in the BRM. From what I understand, the only major difference is the absence of the vehicle speed sensor (VSS) hole on the MK V version (Mk4 obtains the vehicle speed there while the Mk5 uses the ABS sensors). Following.
 

Juls2714

Member
Joined
Sep 17, 2017
Location
Pittsburgh
TDI
06 brm 5speed
I talked to a guy at cascade germen thats based out of oregon they sell remanufactured ones for 2k and a two yr warranty and thats wat he suggested i do or id run into the same problem with blowing out the diff so i know the swap is easy he said 4 out of 5 GQQ coded transmissions he gets back for a core they cant honor bc of the same thing, i wish there was a tech hotline i could call to answer all the questions i have so i can make the right decisions on wat parts to order, the physical swap itself im not worried about. Oh wait isnt that wat this forum is for?????? Someone please help! Lol
 

Bob S.

Top Post Dawg
Joined
Aug 17, 2006
Location
Central MD.
TDI
A B4V, some ALHs & BRMs
Is there a difference besides the VSS sensor mounting hole in the MKV? I know GQQs are getting hard to come by. Bit, 2k for a rebuilt trans is a bit much IMO. The diff. blew apart in my original MKV at about 280K. I was able to find a replacment car, almost identical but with 120K less miles for less than 1/2 that amount. It took some sweat equity to get running. Probably about the same as doing a trans swap.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
You may yet be able to find a clutch housing (the half of the case that has the bellhousing), 0A4-301-107-AG and of course you'd need the diff itself but may be able to use a used one from something.

Some other part numbers to search:

0A4-300-044 (new gearbox assembly)

0A4-300-045 (updated part number for new)

0A4-300-045-X (reman unit, most likely new though)

Not sure what all is different on the 02J from an A4 and the 0A4 from an A5, aside from the A5s not using a VSS (this signal is instead provided by the ABS controller, which all A5 cars have), and no timing plug (the engines used in the A5 all get TDC set from the other end of the engine). I know there are subtle gearing changes. And it may be enough that the ECU won't like it to the point the cruise control may not work properly, not sure.

Another option would be to swap to a 6sp as there may be more donor cars out there (although a lot of potential donors got crushed with perfectly good gearboxes in them).
 
Last edited:

Bob S.

Top Post Dawg
Joined
Aug 17, 2006
Location
Central MD.
TDI
A B4V, some ALHs & BRMs
From my prior research, I think the Mk4 02J would work in the Mk5. But, I had not considered OilHammer's input of the possible cruise control issues. My concern is that Mk4 02J might not hold up to the increased HP & torque of the BRM motor, especially one that is tuned &/or running a single mass flywheel.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
I don't think there is really much "stronger" inside, as most of the internals are the same (they even carry most of the same 02J part numbers). And versions of the 02A/J were used behind VR6s and 1.8t engines as well.

They are generally all very good gearboxes however that specter of the diff pins breaking/sliding out seem to be a possibility for most all tranverse VAG units, even back into the '80s. Even some automatics have done it.
 

mk1chris

Member
Joined
Sep 23, 2020
Location
durham uk
TDI
mk1 golf with pd130 swap ,mk5 ppd 170 bmn daily
if you down mk4 5 speed route youll probably need a flywheel and clutch too ive found the mk5 bellhousing to be smaller than mk4 ...the hard way
i bought a clutch for my mk5 gqq and was sent a mk4 clutch which stuck out too far locking up the engine/box and my starter basically abliterated itself when i went to start the car.. i was sent the correct setup after which was shallower
 

Juls2714

Member
Joined
Sep 17, 2017
Location
Pittsburgh
TDI
06 brm 5speed
You may yet be able to find a clutch housing (the half of the case that has the bellhousing), 0A4-301-107-AG and of course you'd need the diff itself but may be able to use a used one from something.

Some other part numbers to search:

0A4-300-044 (new gearbox assembly)

0A4-300-045 (updated part number for new)

0A4-300-045-X (reman unit, most likely new though)

Not sure what all is different on the 02J from an A4 and the 0A4 from an A5, aside from the A5s not using a VSS (this signal is instead provided by the ABS controller, which all A5 cars have), and no timing plug (the engines used in the A5 all get TDC set from the other end of the engine). I know there are subtle gearing changes. And it may be enough that the ECU won't like it to the point the cruise control may not work properly, not sure.

Another option would be to swap to a 6sp as there may be more donor cars out there (although a lot of potential donors got crushed with perfectly good gearboxes in them).
 

Juls2714

Member
Joined
Sep 17, 2017
Location
Pittsburgh
TDI
06 brm 5speed
I definitely like the idea of a 6 speed swap instead, since 5th gear is for sure to short for cruising at even 75mph. So what are my year make and model doner car options to source one from. From the sounds of it a clutch and flywheel for a mk5 will work with any of the proposed transmission options correct?
 

adjat84th

Veteran Member
Joined
Dec 13, 2008
Location
Virginia Beach, VA
TDI
'01 Jetta TDI/'15 Golf TDI
02Js are pretty robust, mine is running fine at 310k and twice the factory power output.
If you source a later 02Q from CBEA or CJAA, be sure to check that it has brass synchros on gears 1-3 (4th seems to be brass regardless) before you go putting a SMF in there. The steel synchros do not last long and you'll be back in there in short order. Also, 02Ms are always all brass.
 
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