i have a DD371 and a 471 that slobbered more than normal and they also blew oil out the dipsticks .. Were wet-stacking somewhat too .. Both of them had done nothing but easy work (cranes) before I bought the machines .. But before resorting to rebuilding them, I put dragshovel (backhoe) attachments on them and put them to work in the pit at 1/3rd throttle, making them work and lug instead of being wound out.. After almost a week of good hard work, they both straightened right out .. Very little slobber and no more blow-by at the dipstick , and they start better too.. I have to wonder if your "53" needs to get itself a good dose of hard work for awhile