Serial number help

My little book says gas thirty the first one out the door in 1936 second year of production. The SP means special parts likely gearing but could be anything S7 I can't help with that bit. Your example became the R4 in 1938 this was only a name change as far as I know possibly to stop confusion with the earlier model Thirty
Post a couple of photos will help you get more information.
There are plenty of people on here who know more than me.
Cheers from Australia wimmera farmer

based on you serial number it should have thirty on the rad. Starting with serial number 6G875 the name was changed to R4 with production stopping in 12-31-42
Weight is 9390 lbs.
35 HP drawbar
40 HP pto
nebraska test no. 272
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1901&context=tractormuseumlit

Thanks for the information. I'll try to head over and get a few pictures of it. I think he said it has an R-4 radiator. Must be a mixture of a couple different Cats. Maybe we'll pull the winch and see if there is a serial number tag for the machine under it.

Howdy

I would be 99% sure that there is a U in front of the S7. You better tell your friend to have a good look. The reason being some WW2 tractors had US7 at the end of the serial number. SP at the end of the S/N is also very common for WW2 tractors as well because the Milltary often liked to have special features like different gearing, generator and lighting set ups on there tractors etc.

US7 at the end of a serial indicates that the tractor was part of the WW2 US 7th fleet. Other army equipment not just caterpillar was stamped with US7 at the end of their S/N.

If you want to read further about the US 7th fleet refer to this thread with good info from OZD - http://www.acmocbb.org/ACMOC_BB/showthread.php?5117-info&highlight=us7

There is few D4/R4's with US7 at the end of the serial number.

Billy

Hi Billy , Our R4 has US7 on it and our D47J has it also .Ian .

I got a chance to look at the Cat today. Sure enough there is a "U" before the S7. It's hard to see because the "P" from "SP" is actually inside the "U". It does have a gen. and electric start.

based on you serial number it should have thirty on the rad. Starting with serial number 6G875 the name was changed to R4 with production stopping in 12-31-42
Weight is 9390 lbs.
35 HP drawbar
40 HP pto
nebraska test no. 272
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1901&context=tractormuseumlit

Chriscokid - A point of clarification. The top tank radiator change at 6G876 was that "THIRTY" was removed and replaced by "Caterpillar". But the sales model continued as model "THIRTY"" by using the small nameplate tag on lower sides of radiator. See attached photo. The name change to "R4" was later, but the exact serial number for the change is not known.


[quote="chriscokid"]based on you serial number it should have thirty on the rad. Starting with serial number 6G875 the name was changed to R4 with production stopping in 12-31-42
Weight is 9390 lbs.
35 HP drawbar
40 HP pto
nebraska test no. 272
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1901&context=tractormuseumlit[/quote]

sorry for my mistake