5 speed in a 4 speed box?
 

Hi, I currently have a 69 911t with a 5 speed 69 's' box in, the original box would have been a four speed 901/06, if I found a correct case that would close match my serial number and type would the internals fit from my 5 speed or are they totally different internally? Many thanks for your help!

Yep, no difference in cases.

4-speeds are truly rare. Mine is in a '73 and carries a 915/40 designation.

Richard Newton

Is the market really so nuts that a "close to matching numbers" gear box adds value? Certainly no one buying a car to drive would prefer 4 to 5 speeds, would they?

Besides, while the ring and pinion and the 1st gear are the same for the 5 and 4 speeds of that era, the other gears aren't (and while you can put 5th in the 4th gear position, the 5ths aren't the same as the 4th in a 4 speed), so you are going to have to hunt up the innards of a 4 speed, or source used gears (or new replicas) from Mr. Monson or Carquip G-Box or some other seller of gears. But maybe whole 4 speed boxes from that era are scarcer than hen's teeth?

4spd uses A,H,Q,X which aren't terribly rare ratios, however I read his post so say he just wants the right case and will move all the 5spd stuff over. If it were me, I would't bother unless it was the actual right serial number case. Like you say, it likely has nil effect on value.

As an aside, a member here today told me that Stan at Gbox has closed up shop. You might want to ring him and see if he's still in business before sending referrals there.

Hi, thanks for the feed back, the reason for swapping case is due to a crack in the mag, I may just tig it up but contemplated the different casing for ease and slight more originality with numbers , thanks!