3.6 auto to manual

After a long time on this project I finally turn to the original problem that sparked this whole thing off in the first place. The transmission. The auto zf box was slipping/not engaging. I bought a replacement, fitted it, and have not aligned the torque converter correctly and damaged the transmission pump :man_facepalming: Cursing turned quickly into hysterical maniacal laughter at my situation.

So back to square one.

I want it to be manual.

Considering the 3.6 left the factory in auto or manual I’m presuming that mountings and fixtures are already on the car? I.e the gearbox mount, while needing a new one, will it mount into the area that the auto mount was situated? The pedal assembly, if I buy the pedals from a manual 3.6 will they bolt straight in?

I would also really appreciate my shopping list to be looked over:

Getrag 265
Manual prop shaft
Manual transmission mount
Clutch cylinders
Manual ECU?
Manual flywheel?

I’ve heard that the service parts for the getrag 265 are no longer being produced? With this in mind am I better off with a different transmission?
Trying to keep the budget as small as possible…

Some photos of the car as is, still need to flare rear arches, group 44 style, yet not as square and extreme…

As I understand it, the modern Ford Mustang uses a Getrag 6-speed. I dunno which model Getrag. Still, that might offer a source for a cheap tranny.

For your parts list:
Bell housing
Maybe dowel pins to locate bellhousing to block, might already be there
Clutch (Pressure plate and disc)
Pilot bushing
Hydraulic throw out bearing OR
Throw out bearing, clutch fork, slave cylinder

  • Bob

It already has dowel pins from the previous transmission. Fingers crossed the getrag shares the same ones. You’d presume that they’d keep it as easy as possible on the production line in terms of transmission options being similar to install :crossed_fingers::crossed_fingers:

Bob, do you think I would need the ecu from the manual 3.6? The auto trans has no electrical connectivity to the car, so don’t see why it would unless I’m missing something.

Kirbert, thank you very very much for putting the book together. I’ve read it through 3 or 4 times and it has helped me immensely.

Hi Caspar-
I am not very familiar with the 3.6. On the V12, with an automatic, as I understand it, lifting off the throttle disables the fuel injectors until the RPMs drop to something like 1200. This is controlled by a swtich on the throttle tower, I think. It is recommended that this capability be altered/disabled as it can cause stalling on a manual transmission. On throttle lift, the flywheel/clutch doesn’t keep the engine turning as well as a torque converter. Hopefully a 3.6 expert will speak up. @RogerBywater would know 100% for sure.

On installation, be sure to use a dial indicator to confirm your bellhousing is concentric with the clutch.
Plenty of youtube videos show how. Offset dowell pins are the remedy if it is not. Small detail that can make a big difference.

What about the rear end ratio? I believe the are usually 3.54 in the 3.6 manual, is that also true for autos? You want an overdrive-friendly rear end to go with your overdrive manual something in the 3.31 to 3.54 range IMHO.


Sorry in what world dosen’t an engaged clutch keep the engine turning?

I should clarify, the clutch would be disengaged in the scenario I am describing. At say 2000 RPM, push the clutch in and lift off the throttle like you are coasting up to a stop sign. Apparently the aluminum flywheel (used by many in converting the XJS V12 to manual) plus the mass of the clutch doesn’t retain enough energy to consistently prevent stalling when the fuel injection is restarted at something like 1300 rpm. This is my understanding, @Kirbert can probably clarify with some real-world experience.

Dick Maury articulates here way better than I did: Conversion to five speed stalling issue