Project GC8: Wheels, Tyres, Bushings & Finally A Gearbox Fix


With every nut and every gasket replaced, I’m slowly but surely securing the future of Project GC8 – my 1999 Subaru Impreza WRX Type RA 555 Limited, number 371 of 1000.

It’s been a slightly arduous journey since buying the car this time last year. Looking back at that fateful Asahi Super Dry-fuelled night when a bid was placed on the cheapest blue GC8 WRX for sale in all of Japan, I think I probably saved this one from the breaker’s yard.


Fresh Paint

With a disconcerting knock resonating from the engine and a gearbox that refused to keep 3rd gear engaged, the car was not without issues. But I saw potential. I saw a rust-free car with decent paint, which was (by WRX standards) relatively unmolested mechanically and cosmetically. Fast forward to 2022 and the long list of repairs is finally becoming much shorter, and much less costly.

After working out some gremlins with a dodgy timing belt and a filthy throttle position sensor, the rebuilt (in my kitchen) engine is now running smoothly. But my success with the engine had been darkened by the ruined transmission, making driving a real pain in the proverbial. Finally though, after a year of religiously checking Yahoo! Auctions, I managed to buy a replacement Type RA gearbox. We’ll get to that soon.


While I waited for a transmission to present itself, I had plenty of time to sort out a few cosmetic issues, the first of which was the unpainted bonnet. Basically, it was a factory Subaru bonnet supplied with a heavy black protective undercoat. It wasn’t pretty and bothered me almost as much as the faulty gearbox.


A day trip down to Shizuoka Prefecture to visit Ishikawa Body soon fixed the eyesore, and quickly the Impreza went from looking like a junkyard runabout to a respectable street car. Unfortunately, I formatted the flash card I used to shoot the painting process before downloading the images, but you can check some videos on my Instagram.


New Shoes

With the Type RA’s paint looking smart, it was time to buy the old girl a new pair of shoes. This was not only a cosmetic upgrade, but also a matter of safety.


I had been driving around on a set of ancient Dunlop Direzza tyres since bringing the car back from Tokushima, a 12-hour non-stop drive. While the Dunlops would have been decent when new, they were pretty worn and starting to crack around the edges. I knew I wanted to upgrade my wheels, so it seemed like a good time to kill two birds with one stone.


To upgrade from the 16-inch RAYS-made STI option gold wheels fitted to the Type RA, there was really only one option – 17-inch RAYS-made STI option forged monoblock gold wheels. After all, the GC8 is nicknamed the ‘classic’ Impreza, and nothing is more classic than blue and gold for a WRX.


I found a 17-inch set in better condition than my 16s, and ordered some Yokohama Advan Neovas in 215/45R17 sizing to wrap around them. In hindsight, I probably should have gone for a higher profile to give the tyres a more chunky look, but I’m still pretty happy with the way the new setup looks and feel for now.


I think you’ll agree they give the car a much more squared-off look.

Performance-wise, I’ve definitely noticed both the extra weight and the extra stickiness. It feels like more effort is needed to get the car moving off the line with the larger wheels, but it now holds the road so much better.


Keep It Tight

After 23 years and 170,000km of driving, some of which were undoubtedly clocked up on the track, most of Project GC8’s suspension and chassis bushings had turned to mush. Time then to upgrade some rubber for poly bushings…

Along the drive train there are a few points of squishiness that need to be addressed, one of which is the rear diff’s outrigger bushings. I thought these poly inserts with an aluminium collar would help keep things in place – and they did – but the increased NVG was unbearable, so I immediately removed them. I’m going to have to go the more difficult route of pressing out the old bushings and inserting some proper bushings from Whiteline or Powerflex.


With my replacement transmission on its way, I wanted to make sure the shift feel when changing (and staying) into 3rd gear would be firm and positive. These shifter linkage bushings from Whiteline installed easily and have tightened things right up.

I had already installed Cusco engine and transmission mounts when I rebuilt the EJ, but the pitch stop mount had escaped my attention and was becoming more and more squishy. An STI replacement arrived in lovely VCI-Paper (there’s no better feeling) and rectified the problem instantly.


I also found an STI carbon fiber strut tower brace on Yahoo! Auctions – something I’ve wanted for ages – so that went on too.

The Daily Grind


As far as Subaru gearboxes go, the 5-speed is much weaker than the STI 6-speed. On the secondhand market, the 6-speed is, however, almost three times the price of a 5-speed, and that’s before you factor in the cost of the rest of the drivetrain which is required for the swap.

So I decided to find a working Type RA box to at least able to enjoy driving the car for a while before I move on to the next project.


As I mentioned earlier, finding this gearbox has taken the best part of a year. It was only the second one I’d seen come up for sale on Yahoo! Auctions. I missed the auction deadline for the first one and lost my chance, so I wasn’t going to let that happen the second time around. I vigilantly followed the bidding and got lucky.


While the Type RA was not necessarily a rare car, there certainly weren’t as many made as standard WRX STIs, so finding one that still works today is the tricky part. When it comes to their transmissions, the older they get the weaker the gears apparently become, something about stress fatigue. The replacement gearbox I purchased has supposedly travelled 70,000km less than the broken one that came in my car.

Here’s how I did the swap…


Dropping the oil from the ruined box saw an explosion of psychedelic glitter into my oil pan. That’s ground-down gear dust, which despite its JDM-ness unfortunately isn’t worth anything on eBay.


With the car safely jacked up, I proceeded to remove the down pipe, intercooler, starter motor and tail shaft. Then I removed the bolts that secure the transmission housing to the engine block. There are also pins that need to be driven out of the drive shafts and the shifter linkage.

With the transmission supported, I unbolted the its subframe.

Full disclaimer: This is totally ghetto and absolutely not the safest way to be lowering a transmission. But I felt comfortable with what I was doing and took everything very slowly, double-checking the balance of the hefty transmission with every inch.

As I lowered the gearbox backwards and down, navigating the transmission tunnel, the drive axles popped off (with a fair amount of coercion). And with that, the gearbox flumped gently onto the cardboard boxes I had placed underneath for a safe landing.


Getting the 60-odd-kg lump out from under the car was most definitely the easy part. With gravity on my side it was easy enough to do by myself.


Getting the replacement unit in on the other hand would require an extra pair of hands.


New Beatrush transmission subframe bushings at the ready, I organized for my mate Aaron to help lift the new box in. With the promise of a ramen dinner as reward, he was happy to supply some extra muscle.


Aaron drives quite a nice Mitsubishi Galant VR-4 and is partial to a good cuppa.


I won’t bore you with the details of fitting the new gearbox, because it was very much the reverse order of getting the old one out. I will say though, that I’m glad Aaron was there, because lifting the transmission up off the ground and getting it to line up with the engine – even just a foot off the ground – would have been near impossible on my own.

Final Niggles


After a successful installation, a test drive confirmed that the new transmission was trouble-free, and all the new bushings had made things tight and notchy too. But there was still an ungodly noise coming from somewhere, amplified by the stiffer bushings no doubt.

I checked all the wheels for bearing wobble but everything seemed fine, so I moved my attention to the rear diff, which I replaced that with a low-mileage unit from a GD WRX. The noise continued.


It seems that a faulty wheel bearing does not always present itself as a wobbly wheel, so I’ll be fitting a new hub and bearing on both front wheels and hopefully that will sort it.


I’ve also got a box of bushings for diff mounts, lateral links and control arms. Then there’s more paint, interior trim, followed by a some trouble-free, joyful driving. A track day sounds good too…

Toby Thyer
Instagram _tobinsta_


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