Home » Automobile » Mission GC8: Wheels, Tyres, Bushings & Lastly A Gearbox Repair

Mission GC8: Wheels, Tyres, Bushings & Lastly A Gearbox Repair


With each nut and each gasket changed, I’m slowly however absolutely securing the way forward for Mission GC8 – my 1999 Subaru Impreza WRX Sort RA 555 Restricted, quantity 371 of 1000.

It’s been a barely arduous journey since shopping for the automotive this time final 12 months. Trying again at that fateful Asahi Tremendous Dry-fuelled evening when a bid was positioned on the most affordable blue GC8 WRX on the market in all of Japan, I believe I in all probability saved this one from the breaker’s yard.


Contemporary Paint

With a disconcerting knock resonating from the engine and a gearbox that refused to maintain third gear engaged, the automotive was not with out points. However I noticed potential. I noticed a rust-free automotive with respectable paint, which was (by WRX requirements) comparatively unmolested mechanically and cosmetically. Quick ahead to 2022 and the lengthy record of repairs is lastly turning into a lot shorter, and far less expensive.

After figuring out some gremlins with a dodgy timing belt and a dirty throttle place sensor, the rebuilt (in my kitchen) engine is now working easily. However my success with the engine had been darkened by the ruined transmission, making driving an actual ache within the proverbial. Lastly although, after a 12 months of religiously checking Yahoo! Auctions, I managed to purchase a alternative Sort RA gearbox. We’ll get to that quickly.


Whereas I waited for a transmission to current itself, I had loads of time to kind out a number of beauty points, the primary of which was the unpainted bonnet. Mainly, it was a manufacturing unit Subaru bonnet equipped with a heavy black protecting undercoat. It wasn’t fairly and bothered me nearly as a lot because the defective gearbox.


A day journey right down to Shizuoka Prefecture to go to Ishikawa Physique quickly mounted the eyesore, and rapidly the Impreza went from wanting like a junkyard runabout to a good avenue automotive. Sadly, I formatted the flash card I used to shoot the portray course of earlier than downloading the pictures, however you may verify some movies on my Instagram.


New Sneakers

With the Sort RA’s paint wanting good, it was time to purchase the outdated lady a brand new pair of footwear. This was not solely a beauty improve, but in addition a matter of security.


I had been driving round on a set of historical Dunlop Direzza tyres since bringing the automotive again from Tokushima, a 12-hour continuous drive. Whereas the Dunlops would have been respectable when new, they had been fairly worn and beginning to crack across the edges. I knew I needed to improve my wheels, so it appeared like time to kill two birds with one stone.


To improve from the 16-inch RAYS-made STI possibility gold wheels fitted to the Sort RA, there was actually just one possibility – 17-inch RAYS-made STI possibility solid monoblock gold wheels. In spite of everything, the GC8 is nicknamed the ‘basic’ Impreza, and nothing is extra basic than blue and gold for a WRX.


I discovered a 17-inch set in higher situation than my 16s, and ordered some Yokohama Advan Neovas in 215/45R17 sizing to wrap round them. In hindsight, I in all probability ought to have gone for a larger profile to provide the tyres a extra chunky look, however I’m nonetheless fairly proud of the way in which the new setup appears and really feel for now.


I believe you’ll agree they offer the automotive a way more squared-off look.

Efficiency-wise, I’ve positively seen each the additional weight and the additional stickiness. It appears like extra effort is required to get the automotive transferring off the road with the bigger wheels, but it surely now holds the highway so a lot better.


Preserve It Tight

After 23 years and 170,000km of driving, a few of which had been undoubtedly clocked up on the monitor, most of Mission GC8’s suspension and chassis bushings had turned to mush. Time then to improve some rubber for poly bushings…

Alongside the drive prepare there are a number of factors of squishiness that should be addressed, one in every of which is the rear diff’s outrigger bushings. I believed these poly inserts with an aluminium collar would assist maintain issues in place – they usually did – however the elevated NVG was insufferable, so I instantly eliminated them. I’m going to must go the tougher route of urgent out the outdated bushings and inserting some correct bushings from Whiteline or Powerflex.


With my alternative transmission on its manner, I needed to ensure the shift really feel when altering (and staying) into third gear could be agency and optimistic. These shifter linkage bushings from Whiteline put in simply and have tightened issues proper up.

I had already put in Cusco engine and transmission mounts after I rebuilt the EJ, however the pitch cease mount had escaped my consideration and was turning into increasingly squishy. An STI alternative arrived in beautiful VCI-Paper (there’s no higher feeling) and rectified the issue immediately.


I additionally discovered an STI carbon fiber strut tower brace on Yahoo! Auctions – one thing I’ve needed for ages – in order that went on too.

The Each day Grind


So far as Subaru gearboxes go, the 5-speed is far weaker than the STI 6-speed. On the secondhand market, the 6-speed is, nonetheless, nearly thrice the worth of a 5-speed, and that’s earlier than you consider the price of the remainder of the drivetrain which is required for the swap.

So I made a decision to discover a working Sort RA field to at the least in a position to take pleasure in driving the automotive for some time earlier than I transfer on to the subsequent venture.


As I discussed earlier, discovering this gearbox has taken the very best a part of a 12 months. It was solely the second one I’d seen come up on the market on Yahoo! Auctions. I missed the public sale deadline for the primary one and misplaced my probability, so I wasn’t going to let that occur the second time round. I vigilantly adopted the bidding and received fortunate.


Whereas the Sort RA was not essentially a uncommon automotive, there actually weren’t as many made as customary WRX STIs, so discovering one that also works as we speak is the tough half. In the case of their transmissions, the older they get the weaker the gears apparently develop into, one thing about stress fatigue. The alternative gearbox I bought has supposedly travelled 70,000km lower than the damaged one which got here in my automotive.

Right here’s how I did the swap…


Dropping the oil from the ruined field noticed an explosion of psychedelic glitter into my oil pan. That’s ground-down gear mud, which regardless of its JDM-ness sadly isn’t value something on eBay.


With the automotive safely jacked up, I proceeded to take away the down pipe, intercooler, starter motor and tail shaft. Then I eliminated the bolts that safe the transmission housing to the engine block. There are additionally pins that should be pushed out of the drive shafts and the shifter linkage.

With the transmission supported, I unbolted the its subframe.

Full disclaimer: That is completely ghetto and completely not the most secure method to be reducing a transmission. However I felt comfy with what I used to be doing and took every thing very slowly, double-checking the steadiness of the hefty transmission with each inch.

As I lowered the gearbox backwards and down, navigating the transmission tunnel, the drive axles popped off (with a good quantity of coercion). And with that, the gearbox flumped gently onto the cardboard containers I had positioned beneath for a protected touchdown.


Getting the 60-odd-kg lump out from underneath the automotive was most positively the straightforward half. With gravity on my aspect it was straightforward sufficient to do on my own.


Getting the alternative unit in alternatively would require an additional pair of fingers.


New Beatrush transmission subframe bushings on the prepared, I organized for my mate Aaron to assist elevate the brand new field in. With the promise of a ramen dinner as reward, he was completely satisfied to provide some further muscle.


Aaron drives fairly a pleasant Mitsubishi Galant VR-4 and is a fan of cuppa.


I received’t bore you with the small print of becoming the brand new gearbox, as a result of it was very a lot the reverse order of getting the outdated one out. I’ll say although, that I’m glad Aaron was there, as a result of lifting the transmission up off the bottom and getting it to line up with the engine – even only a foot off the bottom – would have been close to unimaginable alone.

Closing Niggles


After a profitable set up, a check drive confirmed that the brand new transmission was trouble-free, and all the brand new bushings had made issues tight and notchy too. However there was nonetheless an ungodly noise coming from someplace, amplified by the stiffer bushings little question.

I checked all of the wheels for bearing wobble however every thing appeared tremendous, so I moved my consideration to the rear diff, which I changed that with a low-mileage unit from a GD WRX. The noise continued.


Evidently a defective wheel bearing doesn’t at all times current itself as a wobbly wheel, so I’ll be becoming a brand new hub and bearing on each entrance wheels and hopefully that may kind it.


I’ve additionally received a field of bushings for diff mounts, lateral hyperlinks and management arms. Then there’s extra paint, inside trim, adopted by a some trouble-free, joyful driving. A monitor day sounds good too…

Toby Thyer
Instagram _tobinsta_


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