BN PTO shaft

Fri Jan 26, 2007 6:15 am

Were there different sized PTO shafts for the BN
I was over at a members home last evening, His BN had straight PTO sized to the cub
and our BN has a standard PTO
His is a 44 ours a 45
Just courious
Thanks Phil

Fri Jan 26, 2007 7:16 am

Hi Phil. I looked at the parts listing on the S/P cd and they show a 1 1/8-6 spline or 1 3/8-6 spline, but I didn't see any 10 spline option.


Fri Jan 26, 2007 10:25 am

Like Rick said, A/B models came with either the older ASAE standard 1 1/8 6-spline shaft or the newer 1 3/8 6-spline. There was an conversion package that IH sold to install the bigger shaft into earlier tractors. Also, used PTO attachments got installed on different tractors so today it is difficult to predict what will be found on any particular tractor. The Parts Catalog doesn't give a serial break, so it is hard to find out when the change happened.

In response to your question, I happened to find the right place to look for the information. According to the '48 Red Tractor Book, the A/B went to the large PTO shaft at seraial number 96390 (start of 1944). So your friend's '44 (if really a '44) should have the big shaft. While on the subject, other models changed at:
H 118000
W-4 7295
O-4 7337
For the H, that would have been during '42, with the others in '43. Since A/B production was shut down in '43, the serial number break for the new shaft was at the time they started back up.

Fri Jan 26, 2007 12:36 pm

Rick it was six spline version.
The fellow believes it to be a 44 a per PO I did not actually look to verify
Thanks Phil