Reply to oldparker:
Well Clint, congratulations on your "new" D4. I hope you have many happy hours learning about it and enjoying it. Very first thing you need to do is acquire a set of manuals starting with "Operation and Maintenance Instructions" that will answer all you questions about the lubrication that you just asked an a whole lot more. Follow this with a parts manual and a diesel engine and pony motor service manual. These books will pay for themselves many times over. They can be had from a Caterpillar dealer or from a lot of sources on ebay. I wish you well. Best regards, John
Congrats on the "new" Cat, typically the final drive cups you mention at the rear of the crawler are filled to their threaded lip, but you need to be certain someone hasn't fitted longer tubes to make lube work easier. On my earlier model D4's the final drive oil cup level is similar to the drawbar if that makes sense, and you will see the drain plugs on the inside at the base of each final drive housing. On my D4's the tranny has a small level plug on the right side of the housing, about half way up, I assume your 29A will be the same.
Most people suggest 80/90w oil here in Oz for tranny and final drives, though I'm sure there are plenty of folks using heavier oil with good results, typically it is related to your average temperatures like any other machine. The suggestion of Operators Books is an excellent one as there are a few not so obvious lube points on those crawlers that catch new kids like me out, don't be afraid to ask questions till you get the books you need. A buddy called by my place yesterday, he has a 30A with electric start on the Pilot motor, that's a nice feature to have.
If you can not be guaranteed on the maintenance history of that crawler I now assume there has been no fresh oil used in the tranny and final drives of any old Cat I buy, ever since that tractor was built. So I now drain those compartments and flush them using petrol or kerosene driving the tractor backwards and forwards for 5 minutes (as per Caterpillar Instructions), this helps dislodge the built up crud and gunge. Drain that flushing agent and replace with fresh oil, but remember to be really careful with the obvious and not so obvious sources of combustion while you are flushing, even though the new petrol here in Oz is rubbish, it still will explodeđmokin:. The $100 the new gear oil costs you is nothing compared to peace of mind knowing everything is back in shape in those vital, and often overlooked compartments.
Contact your local Cat Dealer, or Tillys up in Qld. for motor oil filters, they are only about $15 from memory, check your pilot motor "gearbox" oil level too, you will see a level plug, a lot of folks use ATF there or just regular engine oil. For your bottom rollers and front idler wheels you will need a large volume pump, hopefully you got one with the tractor. I use a heavy oil in my old Cats because they are not working hard and I am then certain the whole bearing is getting lubed, but I believe many folks use the real light OO grease in those plain bronze bearings, check Castrol out because I reckon someone told me recently they had a specific track roller lube.
regards
Mike