I have the chance to buy a D4 with serial number 4H9709SP. It is a dozer with hydraulic blade, in original unrestored condition but hasn't run for 20 years or so. My questions are: Approx what year is it, how much is it worth, and what does SP stand for ?

I have looked through my Cat SNID book and I can,t come up with a D4 with that serial number. SP means there was some special ordered parts assembled into it at the factory, could be transmission gear additions etc.Normally there was a serial number on the left side of the engine block and one back above the drawbar on the back of the trans. case so check both places and see what comes up.

hello sumitomosh60, the only 4h is a D4400 industrial engine.the D4400 was fitted to the d4 ,it looks like your tractor has been refitted with another engine .
the D4400 was fitted to the models d4 7J ,2T ,5T ,produced from 1939-47.
in 1947 when the 6U-7U was made ,it had the D315.
IF you look at the back of the tractor about the draw bar you will find a brass plate with a serial number that will give you the tractor number,
hope this helps ,bruce oz

I have a d4 SN 5T12(or maybe3)88sp. any info about it would be nice. was running when parked 10 years ago. originally orange in color. in fair shape.

Thanks for the info fellas, i have a wire brush and a torch on my shopping list.

Hi Bruce,
Got the number from the rear plate on the D4. It 7J257.
Can you date it from that ? also, how many of that series were built ?
Cheers.

7J model production was from 1939 to 1943 with 9,999 models produced.
Yours would be an early 1939 model.

Sumitomosh60,
My book shows your 7J257 as a very early model 1939 as OM as stated., There were 1754 tractors build that year.
Kelly

Thanks for all your help chaps.