where to find S8 manual euro LHD gear box
 

where could i get hold of a 6 speed manual gear box for the A8 i know the rs4 gear box will mate up but if there is already one for the A8 then i would rather that ? any ideas ?

Try here or here

have a read of this, I think Gabor used a S4 gearbox.
http://forums.quattroworld.com/a8/msgs/12898.phtml

wow im so intrested in doing this i think the power would be put down to the road much better through a manual box if that box is off an a8 already would the shafts be the same ect and it would mount straight up if so i think it would be worth the money

Don't underestimate the amount of work requird here Guy. You can buy a gearbox, half shafts, gear selector mechinism but there is no pedel cluster or wiring loom for RHD cars so they would have to be fabricated/modified to fit.

RHD cars IMHO were not designed for manual, because the footwell is too tight for 3 pedals because of electrical box. Stock pedals for RHD cars don't exist.

Also, each gearbox comes with enique rear drive. If we just blindly change box chances are rear wheels will rotate with different speed.

It is much easier to completely repair faulty gerabox than changing it.

Conversion to manual also needs different rear differential, different propshafts and driveshafts, plus flywheel and clutch, gear selector and pedals. Footwell is too tight not only because of electrical box but also footrest on the left and there is starter motor behind it so You cannot just chop it off an cover with something else. Footwell on A6 is 40cm wide, A8 only 30cm so very tight indeed.

And A8 ECU has no coding for manual box as there was no manual A8 just S8. So it will be looking for communication with TCU and without it will go in limp mode not to damage gearbox. On S8 it is simple 2 min recoding with VCDS on A8 you would need either custom firmware made and flashed to ECU or leave TCU connected together with gearshift mechanism in P or N. Might also need to emulate some sensors from gearbox to TCU( temp, oil pressure) so that it does not pick up some errors and request reduced torque from engine.

Getting all genuine S8 parts will be quite pricey.

Apparently to save money You can use 6 gear box and rear differential from A6 C5 2.5 TDI quattro but would need to modify/fabricate propshafts and driveshafts out of A6 and A8 drive and propshafts. Roughly speaking £300 for gearbox, £80 propshafts, £80 rear diff,driveshafts £30 each if I remember correctly. Might also need to make some custom mounts for box or diff not sure if they are straight fit. I was thinking of manual conversion when I first got S8 3 years ago but decided to hold off until it brakes down because of cost and work required.

Now DSG gearbox would be something, no need for clutch pedal.

where on earth would i get a DSG box for an A8 that must be like finding rocking horse S**t they are a great box though two clutches and always in the next gear ready for the up shift instant gear change +++

iirc you are best using a 6 manual box from a tdi but it is very pricey as has been said in previous posts and an awefull lot of work .........have you not thought about sending an an 8 Tc to the states and getting it uprated and rebuilt to your specs? That's what I have done with my car:ROFL:

you have done what !! ? you sent your box to america to get rebuilt to your spec ? may i ask what that involves and what spec it is that you have built it to ?