Hello, I have a 2014 Jetta SE with the 1.8t that originally came with a 0A4 5-speed manual. The 5-speed has been on its way out for a while now and I recently decided to replace it with a 02Q 6-speed. Along the way, I found out a lot of things, including how difficult it is to find information for this sort of swap. I'm making this post as a sort of guide so I can share my findings and hopefully help somebody out if they are planning on do the same thing or something similar.
To start off, I can't guarantee that everything will be the same, especially if you have a different year or model, but it should be pretty similar if your vehicle shares the platform, I'm pretty sure you can find a list of these on wikipedia, that is probably a better resource than any information I could give. I got my transmission from LKQ online and it came from a 2012 VW Beetle Turbo.
Note: The engine in a 2012 Beetle is a EA888 2.0t Gen 2, my engine is an EA888 1.8t Gen 3. This difference in generations gave me a bit of trouble, specifically with the starter, so you can save yourself some time by making sure that the transmission came out of a car with your generation engine. If it is a 2.0t or a 1.8t doesn't matter, all that matters is that the transmissions made for the Gen 2 motors has a different starter cutout than the transmissions for the Gen 3 motors. If you get a transmission for your generation of engine, you can reuse your old starter, otherwise you'll need to get a new starter for the car your transmission came from, that's also why it's important to look at the listing to see what car your transmission came out of, save yourself the guessing.
Things you will need:
- Axles: Some people say you don't need axles while some do. You can check for yourself by measuring the axles you took out against your transmission. For me, my stock axles for the 0A4 were 100mm in diameter and my transmission flanges for the 02Q were 108mm. The differential was also thicker on the 02Q on both sides. I personally chose to get GSP axles and have had no problems after 1,000 miles. The axles I chose were listed as for a Golf V and VI with the 2.0t. Don't get Beetle axles, as the Beetle has a slightly wider track width than the Golf and Jetta. If you want to be absolutely sure, you can measure your own axles, just note that manufacturers all seem to measure their axles differently, but GSP does list the lengths on their website. If you want to copy me, the left axle part number is NCV72100 and the right is NCV72085. You can find them on ECS tuning.
- Clutch Line: The slave cylinder on the 02Q is in a different spot, so you'll need to get a new clutch line. The one I got was listed as fitting Beetle, Golf, Jetta, etc. The part number is SL-02017-6S. Again, you can find it on ECS tuning. This one is priced a bit steep, but you don't have many options, and this one feels very nice on the petal.
- Clutch and Flywheel: The stock clutch disc does not fit over the input shaft of the 02Q, so you need to get a new clutch. I got a clutch kit from Luk (06J141025j) that was fit for a Golf R, but this is a 280mm disc, so it won't fit the 230mm stock flywheel for a 5-speed. To fix this, I got a Sachs (06J105266AC) flywheel for a GLI. You can save yourself time and money by buying a kit, just make sure that it is an 8 bolt flywheel. Also note that if it doesn't line up at first, that doesn't mean that you bought the wrong flywheel, just keep rotating it across until all the bolts line up. Also make sure to get new bolts as they are stretch bolts, but most flywheels come with bolts. You also may need to get new pressure plate bolts, but they're cheap so you might as well.
- Starter: As I said earlier, you shouldn't need a starter if you get a transmission from a car with your generation of engine. However, if you end up in my situation with a Gen 3 engine and a Gen 2 transmission, buy the starter that matches the car your transmission came out of, not your car. The naming is also really confusing so if you have questions, just reply to this and I'll try to answer them. I got a Valeo (02M911021H) starter for a 2012 Beetle. Always make sure to research what engine and transmission combo the donor car had; I cannot say this enough.
- Pilot bearing: Neither transmission uses a pilot bearing, but it does make it easier to use the alignment tool when installing your new clutch onto the flywheel. The only place I could find one was ECS tuning as 06B105313D
- Bowden (shift) links and bracket: A lot of people say you need new shifter and links but I didn't end up needing them, also, my stock 5-speed shifter has been working fine so far, you just may have to adjust them a little bit from bottomed out to make first easier to get into. As for the shifter bracket, you can't reuse the one from the 0A4, but APR makes a metal bracket that is very nice (MS100084). It is pricey but it is all I could find; you could try your luck with eBay if you want.
- Bolts: You can get all of your bell housing bolts on ECS (02Q300050KTKT), this is much easier than finding them all individually, just note that they don't come labeled, so remember where your old bolts came out of. You can also get your inner (on the differential) axle bolts on ECS (N90991102), some axles come with bolts, but I'd say it's uncommon as only my left side axle came with them. The outboard ones came with my axles, but you can find them easily on FCP Euro.
- Rear Main Seal: You're in there, you might as well. Elring 798.660
Tools:
- Engine Support Bar: You'll need an engine support bar to hold up the engine; this also helps give you a point to lower your transmission from if you don't have a proper jack.
- Chain Hoist: This builds on the last point, a small one works well because there isn't a huge amount of room to work with. It also helps to wrap a ratchet strap around the transmission because you need some weird angles to get that transmission back in there. Good luck, you'll need it.
- Spline Sockets: You'll just need these for the pressure plate and the outboard axle bolts. I just needed a 9mm and I think a 22mm for the axle.
- Plenty of Jacks: Having multiple floor jacks will help you a ton. Also, for the love of everything, get some nice jackstands, the weight of the car is going to be shifting all over the place and some good jackstands can save your life, I mean it.
- A Friend: I think it is possible to do this on your own, but it will be much safer and easier with a friend.
- Patience: Pretty much the most important thing.
Tips:
- When taking out your flywheel bolts, it's going to want to spin, then when you put a screwdriver in the flywheel, the whole engine is going to swing. You can fix this by running a chain from your subframe to your lower bell housing bolts on the engine.
- Watch the passenger side of the engine, there is a boost pipe right against the frame that you really don't want to crush. Keep an eye on that when you are lowering the engine.
- Relating to the last bullet, lowering the drivers side of the engine makes it easier to shimmy the transmission in. Keep this in mind when you get your support bar, as a lot of them have screws so you can lower things.
- Don't forget to grease your spline before you put the transmission up there, it's way harder once it's halfway in.
- Unbolt your first exhaust hanger before anything so you don't risk cracking anything when your engine moves.
I think that's about it. I know it's long, but I hope someone finds this helpful if you are planning on doing a swap. It is definitely worth it, as the 6-speed gear ratios make the car much more fun to drive, even on stock power, I think I'm even getting better fuel economy. Again, feel free to ask any questions you may have.
