Clutch size ID

Reply Subscribe

Thread Tools

Search this Thread

Mar 6, 2019 | 05:00 PM

Gabes50

Thread Starter

Freshman User

Joined: Sep 2018

Posts: 32

Likes: 1

Clutch size ID

Need some help finding out my clutch size, I have a 1950 F1 with a 226 and a 4 speed non synchronizer transmission. I have acquired a light duty 3 speed and the appropriate drive shaft, I would like to replace the clutch while we’re changing transmissions. What size is it and do I need to change the size for the light duty? Any help would be appreciated

Mar 7, 2019 | 06:51 AM

TitusDH

Senior User

Joined: Oct 2017

Posts: 237

Likes: 0

From: Hamburg, Germany

Hi Gabes,

the 4 speed spur gear crash box usually came with a 11" cluch, 70 years ago. The spline of a 3 speed light duty gear box and the crash box are not the same, to the best of my knowledge.

Anyway, you'll need a flywheel correctly drilled for the clutch, if you need to change the clutch along with the gear box. I doubt there is a 11" clutch disk fitting to a 3 speed gear box spline available.

But all of it starts with the setup you actually have in your truck now.

Wil

Mar 7, 2019 | 09:15 AM

ALBUQ F-1

Fleet Owner

Joined: Jul 2004

Posts: 27,294

Likes: 1,055

From: NM

The 4-sp's did come with an 11" clutch, 3-sp LD came with 10". You can use the 11" clutch with a 3-sp, but can't use a 10" clutch with a 4-sp. Both are 10-spline and have the same input shaft spline diameter.

Read this thread for info on how to identify your clutch before you pull it. If you have it off, just measure the disc.
https://www.ford-trucks.com/forums/1...tch-sizes.html

Mar 7, 2019 | 04:52 PM

Gabes50

Thread Starter

Freshman User

Joined: Sep 2018

Posts: 32

Likes: 1

So Albu, it sounds like the LD 3 speed would bolt right up to the 11” clutch?

Mar 7, 2019 | 05:53 PM

ALBUQ F-1

Fleet Owner

Joined: Jul 2004

Posts: 27,294

Likes: 1,055

From: NM

The hub length on the disc is different, there is a thread where it was discussed. I'll see if I can find it.

Mar 7, 2019 | 07:03 PM

Gabes50

Thread Starter

Freshman User

Joined: Sep 2018

Posts: 32

Likes: 1

Thanks, I really appreciate your time on this!

Mar 7, 2019 | 07:24 PM

ALBUQ F-1

Fleet Owner

Joined: Jul 2004

Posts: 27,294

Likes: 1,055

From: NM

Here it is: https://www.ford-trucks.com/forums/1...ems-still.html

Bottom line, he found the longere hub on an 11" disc hit the front bearing retainer on the LD trans. So he used an 10" clutch, had the flywheel redrilled, but you can use a 10" disc with an 11" pressure plate.