If you have a higher powered g40 and what to replace a broken gearbox we all know trying to find a secondhand g40 box is near impossible due to the rareness of them.

So what can we use instead even if its just a tempory thing.

I personally am currently running a 1.3polo gt box and is ok just slightly diffrent ratio's but no drama

I think maybe a diesel gearbox? but i think they are no more stronger?

Does anyone have any ideas and has anyone done a gearbox change to somthing stronger?

I have studyed the thread on the forum about lsd's ect and i understand this is the real way to go but thats not what I'm asking here for now, i just what to know what gearboxes will fit the g40

thanks for any help guys

Edited 8 June, 200719 yr by matt-lmr

Having broken 5th gear in my 1.6 MK2,i also need to know this. What makes the G40 box stronger? I'm hoping there's going to be quite a choice of later units in 1.6 Polo's and Golf's - but I've not yet looked into it,and i dont fancy a cable shift or fabricating alternate mounts. I'll be looking into this late next week,i hope to be more helpful then lol

It was many moons ago but I'm sure I read somewhere that 6N 16v boxes fit on a G40. Maybe worth doing a search see if you can find the thread.

Sorry I can't be more help than that!

The G40 'boxes are no stronger than any other Mk2/3 Polo 'boxes. They're all equally shit.

A 5-speed 8P 'box will give you the closest ratios to a G40 one, but it's still a fair bit shorter geared.

6N/Mk4 'boxes do fit, but you need to grind off part of the rear mount, and might need to change the output flanges as they appear to be slightly longer. Some of the 6N 'boxes use larger diff bearings, and larger diff pinion gears than the earlier 'boxes - but it doesn't seem to make them any more reliable.

Serious power and torque (along with naughty tyres and LSDs) tends to break diff bolts (in the case of bolted-on final drives), 2nd gear can take a pasting too. 5th tends to go due to oil starvation, though if you're running higher forced induction torque levels it doesn't help.

I don't know about intermediate ratios but iirc top gear does mph/1000rpm.....

4spd 17.9

gt 18.9

mk4 1.3 & 16v 18.6

4+e 21.4 (4th 17.9)

G40 21.7

mk4 1.4 22.summat

Probably a couple of points out on those but they're near enough.

G40 (ATV, CEK) is 22.3mph/1000rpm in 5th.

Polo CL 'box (8P, CEG) is 21.0mph/1000rpm in 5th.

That assumes you're using stock G40 size 175/60 R13 tyres. Doesn't seem like much, but you notice it!

The Mk4s have a huge number of different ratios, not quite sure why either. I've not bothered to make a spreadsheet of all the Mk4 ones yet, but seem to remember there were only a couple of Mk4 'boxes that were comparable to G40 ratios.

Means the G went a bit better than I thought (also means I shouldn't believe everything I read ).

Defo notice every change in profile, even 60 to 65 or similar. Might just make the speedo more accurate as well (GT overreads by 10% ).

I'm not bothered about gear ratios,other than to have them long enough for comfortable cruising at speed. I just need one thats strong enough. If they're all the same,I'm going to be getting through 20 gearboxes a year at the current rate. Better try a 16v unit,i suppose.

I'm not bothered about gear ratios,other than to have them long enough for comfortable cruising at speed. I just need one thats strong enough. If they're all the same,I'm going to be getting through 20 gearboxes a year at the current rate. Better try a 16v unit,i suppose.

Can someone (if they know) list what excact gearboxes will definiatly fit the g40? with no or little moddification. please

All Mk3 'boxes will fit. Most (all?) Mk2 will fit too, and Mk4 can be made to fit.