Hey guys I've done a few searches and looked through the parts book to my machine which shows 3 different possible bolt and nut combinations for the track pads on my D4 6U, I pulled an old bolt out and it measures about 9/16x1-3/4. Does any one know the part number for that size track bolt and nut to match?

Cat lists a 1 5/8" long bolt 4K7038 and 7K2017 nut. Yours was probably a hex nut and lock washer, Cat now uses the shorter bolt with the square nut now.

Ok next odd ball question I saved a set of freshly rebuilt track chains and pads from the scrap yard but those like the book say only have 31 links/pads.....my old track on my machine actually have 32, both are 4 roller side frames....and my tensioner is not all the way out was there a different option for say a larger idler or somthing that allows for 1 extra link/ pad??

Just went to re- measure the bolt I took out it is definitely 1-3/4 long and had a square nut on it with no lock washer.

Ag tractors had smaller idlers than tractors equipped with a dozer arrangement. Are the bolt threads flush with the nut or out past when assembled?

Some are flush some are out, whoever did the last "rebuild must have saved some of the older bolts that would use a lock washer.

I appreciate your help Rome, now to find 2 new pads to make a set for my tracks