2.9L and M75 gearbox

[James]

Hi,
I am in the process of a complete rebuild of one of my 3 Berlinettas. It is RHD and had up till now a 2 litre pinto engine and a type N manual 5-speed gearbox. I have been offered a low mileage Sierra with a 2.9 litre engine complete with a type M75 manual 5-speed gearbox. There seems to be plenty of room for the engine and the gearbox looks even narrower than the type N. I am a little worried about the mating of the gearbox with the propshaft as the M75 seems to have a large flange that also looks to be too big to go into the transmission tunnel. Before I get started I would like to have some idea of what I am getting myself into.
My questions to anyone who has experience of this are:
Did you have any MAJOR problems in fitting this drivetrain? How did you mate the M75 gearbox with the propshaft?
I am grateful for any advice on this even if it is “just forget it”.
Thanks from James in sunny Sweden.

[pdm_engineer]

Re: 2.9L and M75 gearbox

Hi James
There is a Ford alternative output flange for this gearbox, as used on Transit vans, and the Ford part number is 6171398. This converts the G.A.F rubber coupling to a standard 4 bolt UJ coupling.
I have used this part myself on my Ford engined Cabrio so I know it works.
Sorry but I Can't answer Berli specific questions.

[James]

Re: 2.9L and M75 gearbox

Thank you Peter.
It sounds as if the M75 is a possibility and your information with the Ford part number makes my life a lot easier.

[Dane_Rescueman]

Re: 2.9L and M75 gearbox

Note that if your Berlinetta is Cortina based, the prop shaft needs to be able to move longitudinally due to suspension movement. The type 9 G/B allows for this by the sliding spline entry for the prop shaft. It would be posible to modify a later two piece prop shaft to allow for this. If your Berli is Sierra based then it will not have this problem.

[James]

Re: 2.9L and M75 gearbox

Thank you Dane,
Sod's law! - I have a Cortina rear axel. You do in fact had confirm my own thoughts about the back axel movement. I need to take another think about this.

[keith_h]

Re: 2.9L and M75 gearbox

The Sierra based Roadster takes an M75 attached to a 2.0 DOHC and I am pretty sure that is the same setup Bob Cawte has in his Berlinetta but I don't know what his rear suspension is based on.

[csjcarolyn]

Re: 2.9L and M75 gearbox

The MT75 gearbox is better than the type 9 BUT fits with a lot of work, YKC told me the gearbox panels have to come out and the floorboards have to be cut to accept the newer larger box - in addition to the problem with the modified propshaft. I thought about this when I fitted my 1.8 Zetec and fitted another type 9 instead.