OMG ... My gearbox exploded! Again!

[geoff_gti]

Driving down south on Friday for the long weekend, my gearbox exploded, again! Was cruising along in 5th, when there was a pretty decent bang and the car popped back into neutral. I thought it was the clutch, but when I reengaged 5th it just revved through. Dropped it back into 4th and realised 5th had snapped off, as the clutch was fine but the rest of the gears were now clattering badly! It's punched a whole through the bottom of the gearbox too as I could see the oil dripping out once I had stopped. Ended up getting towed home from Pinjarra, luckily within the RAC 'free' towing zone.

BIG thanks to Matt for doubling back and giving me a lift!! You are a legend dude!!

Having just spent a reasonable sum on a new slave cylinder and associated gearbox 'parts' not much more than 6 weeks ago, needless to say, I am less than happy! I'm not here to name names etc, and most of the local guys know what happened back then as it was posted elsewhere...

So, since the Mk IV gearboxes seem to be a bit of a weak point anyway (rather than me just lucking out big time), & my mechanical knowledge is very limited, what I am looking for are some suggestions about what I can do going forward from here.

I have a 2003 GTI, with the Oettinger chip and K04 upgrade. The car clocked over 75000km just last week.

As I see it, I can try and get this gearbox fixed up (which I don't think I would want done anyway), or buy a second hand / recon unit. Can the internals of these 5spd boxes be strengthened etc to hopefully prevent this from happening again?

The R32 & V6 Boras have a 6 speed box, which I am also assuming would be stronger too. Given these are AWD though, can the same box be fitted to a GTI or would it need a lot of fiddling to fit?

Golfloon, you might remember me calling you about 6 weeks ago when it went the first time. If you, or any others, could PM indicative prices or availability etc inc estimate freight prices that would be great. I am in Perth metro.

I am also looking for least-cost options since I'm supposed to be going to NZ in July and have already paid for the flights. I'd just got over paying the first hit on the repairs before, but depending on how much this is likely to cost, I'm hoping I can still make the holiday!

TIA guys!
Geoff

[h100vw]

I don't believe there's anything wrong with the basic design except for the rivets that hold the diff together.

Any box you fit should be split and have them replaced with bolts. Although if that's not done correctly the same result can be expected.

I had 165KWATW of my A3 and the box was solid. Still in my garage if you get the point where you need one and there's none around.

Gavin

[geoff_gti]

Cheers Gavin, I don't think it was the rivets that went the first time, although I'd heard that was the 'usual' fault when things go wrong. There's no mention of them in the list of parts replaced anyway.

[h100vw]

They would have replaced them with bolts so wouldn't have been mentioned. Who did the job, not looking for name just the pedigree of the place, VW specialist or dealer?

This is one that Jimmy would explain best I think. He knows the insides of these boxes well.

I wonder if some debris from the first failure was missed causing the second one?

Gavin

[geoff_gti]

It was done by one of the local specialists.
I was wondering the same about some bits etc left over from the first job, but you'd think the whole box would have been cleaned out properly before they put it back together... Anyway, will be making a few calls tomorrow.

[h100vw]

If the oil is now on the outside, it had to be pretty catastrophic and the commonest thing for that would be the diff rivets. They show no mercy and punch through all over.

Best to keep your hair on and let the specialist do the talking. Make it a bit awkward by asking a question and then leaving them to reply. As the box wasn't new you will be relying on goodwill I feel. Obviously whatever they fitted will be warranted but proving what caused the failure will be pretty hard.

Gavin

[geoff_gti]

Cool, thanks for the info. The parts which were replaced recently in addition to the slave cylinder were things like the needle bearing & washers etc, not like they have replaced the individual gears, so I think it's still my original gearbox in there - it just got an 'overhaul' so to speak. Just hoping they give warranty on what was done before and I don't have to pay for all that labour time again I was planning on calling around for some info and indicative prices etc tomorrow, not actually as angry about it as my first post might have sounded haha

[h100vw]

You didn't sound angry but it's worth keeping calm about the incident for the best outcome.

Best of luck

Gavin

[geoff_gti]

Indeed. Thanks again!

[Golf Loon]

They are a week point to the car and good second hand ones are hard to find and expensive.

I reckon Gavins box might be the cheapest option, I think he only wanted $1200 or so for it?

[evorobin]

To let go at cruising speed in 5th is beyond questionable...

[geoff_gti]

Well the Golf is back at the workshop now. Had a chat to the guys there, so they are going to make an assessment of it & we'll go from there. Looks likely I'll need to get a recon / 2nd hand box otherwise the labour etc to repair this depending on what's actually happened could outway the cost of just getting another box. Thanks for the replies & PMs so far - I'll keep you posted...

[zz2]

i didnt know you had a K04?!
what sort of power are you putting out with that?

can you buy stronger gearbox internals for mk4s?

[geoff_gti]

It's supposed to be close to stock MkIV R32 type figures according to the Oettinger site, so about 160kw but I've not had it dynoed. I got a 14.3 at Kwinana if that gives you an idea.

I'm not sure if the internals can be strengthened apart from this issue with the rivets. That was why I was wondering about the 6 spd box from an R as you'd think it would be stronger to begin with, but it would need work to fit FWD.

[h100vw]

Std boxes are plenty tough enough IMO. I had 165 KWatw of my A3 with no dramas.

No need to go spending money uprating the gears and the like.

Gavin