Diesel Gear Boxes can I have a 6 Speed

Adstar · Unread post by **Adstar** » 06 Feb 2006, 12:53

After a few trouble free months of motoring, I am trying to work out my options for solving my uninterested non commital speedo.

My guess is either replace the little plastic gears and hope they last a while, which will involve the box coming off. Or replace the gear box (which will have new plastic gears in anyway by the time Im done!).

If gear box replacement is considered, I would REALLY like to slap on a 6 speed box, mainly for the better economy.

Are there any that will fit a XUD turbo diesel block. I have a 605 2.1TD. I was wondering about things like the 307.

Anyone any ideas on the compatability or am I stuck with only 5 gears?

matt · Unread post by **matt** » 09 Feb 2006, 23:03

Never seen it done on a diesel but plenty of 205 owners use the gti6 box from the 306.I would have thought aslong as its an xu lump it should fit,trouble is,finding a box as they fetch good money,hope this helps.

Adstar · Unread post by **Adstar** » 10 Feb 2006, 09:34

Thanks for your reply. I was aware of the GTi 6 and also things like the 307 HDi which have a 6 speed box. This was the reason for my question.

Even if they were compatable, the problem with fitting the GTi6 box to a diesel unit would be the torque handling. The gearbox would probably not last too long. (assumign I culd get driveshafts to connect it to the wheels)!

I have spoken to an expert who has not only provided me with the confirmation that there isn;t a compatable 6 speed box for the XUD engine, but he may have also provided the solution to my errant speedo problem, which may be electrical after all!

So I will just have to make do with my 5 speeds.. and hopefully one day soon I will know exactly how fast I am going all the time rather than when the car sees fit!

Harlequin · Unread post by **Harlequin** » 10 Feb 2006, 11:31

2 reasons to not use a gti6 box:

1) steering - it actually effects the steering as its shaped differently to the XUD box and reduces the lock to the point where on right lock teh wheel hits the gearbox (iirc)

2) the raios are wrong for an XUD - you`ll get about 100mph MAX bouncing off the rev limiter in 6th.

fastandfurryous · Unread post by **fastandfurryous** » 11 Feb 2006, 18:17

Surely this is a completely pointless modification. The 5-speed BE3 box on a 2.1TD has ratios matched to the torque curve of the engine. Fitting a different box is almost guaranteed to mean bad matching of ratios to the engine.

Plus... the number of gears in the box is not the important factor.. it's the top ratio. What might be a better mod would be to fit a higher 5th gear ratio. It *might* lower your fuel consumption (a bit) but will certainly make the car less responsive in top gear.