Hi, I have an old D4D (1969). The clutch brake will not stop the drive shaft turning unless I reduce the revs to as low as possible and even then it takes a while to stop. I've read posts here about this problem and repaired the linkage as suggested and I've replaced the brake. It definitely helped. With the engine stopped and the clutch disengaged I can use a short bar and manually turn the drive shaft although I can feel some drag. The previous owner told me that he put in the wrong oil which was much heavier than what was needed. Could this cause the problem I am having or is something else happening? I'd appreciate your input. Thanks John
wrong oil will certainly cause a issue. Usual oil for master clutch is TO4 grade, 30 weight. But if its below freezing temps a TO4 10W oil would be better Also clutch linkage needs to be adjusted so when lever is hard forward, clutch brake is pushed fully on. Never had any clutch or clutch brake issues on my old 78A D4D; but everything is right on mine
Thanks guys for your input, I'll change the oil
I know this is a tad old and you probably have the solution by now, but I'm not really sure on the D4D, but a D6C straight drive had a type of pilot bearing with a 2 piece race and I think it was 3 little keepers (been 25 years since I have replaced a dozer clutch). Had one to loose those keepers once and a roller out of that bearing got between the fiber and it would come out of gear like normal, but you couldn't stop the clutch. But you could tell something was wrong because the clutch lever got hard to engage. I have a D4D but the clutch hasn't ever even slipped yet since I have owned it. The D333 turbo D6C dozers would slip a clutch easily in 2nd or 3rd gear. D6 Merv is the go to guy on these things. He knows about all there is to know on the D4D.