1958 d4 7u or 7j

No expert here, but apparently all the CAT series before the U's stopped at 9999. This sometimes resulted in identical machines manufactured one behind the other on the line being in different series. Starting with the U's, machines were numbered with up to 5 digit serial numbers, so there was usually a significant redesign whenever series prefixes changed and the sequential numbers started over.

I suppose you could have a tractor that was put together from major components of the J and U series. I have heard of that being done with motor graders, not sure what was possible on the tractors though. Could also have a poorly stamped plate where the U came out looking lime a J.

Pictures would surely help and post the serial numbers.

Early series machines had suffix letters like W to denote Wide gauge and SP to denote special parts installed on the line.

Another thing, until the 1970's the serial number of the tractor or other machine would match the engine serial number. That changed when engines began having their own serial numbers and build codes etc.

One thing that is very pertinent to your question is whether the tractor has an oil clutch. I think by 58 the 7U would have had the oil clutch standard.

Ron--this is your 4th thread on the same subject so it makes it a little confusing to follow---also some pictures would be helpful.
anyway HO Penn is my dealer on Long Island---are you nearby?
Dan

yes I am in ct ,as far as the clutch when I took off the cover infront of the shifter there is oil in the bottom the serial number is 7j38803 I do have pics how do I go about posting. thanks again ron

7J model only went to 9999 in 1942----7U38803 is 1956

to load pics do the following
scroll down to upload file icon--click on it
click on add file
click on select file
click on your pic
click on open file
click on upload
click on insert

if your in western Connecticut I may be able to stop by as i take I684 to and back from MA

7J model only went to 9999 in 1942----7U38803 is 1956

to load pics do the following
scroll down to upload file icon--click on it
click on add file
click on select file
click on your pic
click on open file
click on upload
click on insert

if your in western Connecticut I may be able to stop by as i take I684 to and back from MA

j a u??????? d47u? u better ferry over dan………..