Series 60 bull gear

Pull off the accessory drive pulley. It is only five bolts. Once that is out you can see the edge of the bull gear. (The bull gear will drive the accessory drive gear.) What you can do is actually grab the gear and see if you can wiggle it front to rear. If you can it shows the bearings are worn. Also, bar the engine over and check all the teeth for any broken or chipped. If it feels fine and looks good I would run with it.

 

Mine just went bad at 1.1 million on my truck. It was making noise and damaged several other gears. Total cost was $4100 for the repair. Just to do the Bull Gear its $2600. The DD tech told me they should be replaced around 850k, take that for what its worth. Good advice by Heavyd.

 

I know several detroit guys who had problems with the bull gear. either the gear or the bull gear bearing. I have the 11.1 ser 60 it has a different bull gear. mine is still good at 1.4 mil miles. this summer I may take another look at the entire gear train, but when looked at when inframe done, everything o.k. & I figured enough spent already & downtime, let me recoup some of my money & then we'll check the gears again. definitly have yours checked. I dont know why the 11.1 holds up, but the 4 guys I knew that had them, never had a problem even past the mil mile mark. the 12.7 guys had problems 750,000 to 900,000 miles. & you can hear the noise by putting your ear right next to front of grill where radiator is.

 

When it comes to money & it's not broke at the time, many would not replace. as far as not checking? a sloppy mechanic or lazy worker, could just look at gears & if IT looks o.k. then good to go mentality. all depends on who you have looking at truck. however even honest veteran mechanics can miss some things. mine has. have it checked. good luck.

 

Are you saying I am a sloppy, lazy mechanic heavyhaulerss? Yes, I believe in replacing the bull gear after a million miles. At the same time, most O/O don't want to spend $2400 if they really don't have too! Can you blame them?

 

No not at all. just saying in general. you know you go into some shops, like the quick oil change & see some youngsters, who you know they hope you don't want any work done. I have had known of top notch mechanics miss some things, just one of those day's where they realize after the fact of the error. I would spend $2400 in a minute for preventative maintenance. especially something that could cause the damage the bull gear would cause.

 

I will be more specific due to my experience. when I found metal flakes on my oil plug, 4-5 friends of mine claimed they would bet is was from the teeth of the bull gear. all had problems with the teeth on there bull gears or had knowledge from many others on this problem. I talked to my mechanic. he said, a part of a tooth off a gear may be from bull gear, but from my description, it sounded like flaking from the cam or cam bearings. I also brought him the oil plug, so he could look at the metal. very fine, thin, almost like the ole school glitter. after looking at cam, it looked like new. after 1.3 mi miles, I dont see how, but it does & I had pic's posted here somewhere. anyway, after that. then the idea came up, bull gear bearing? so he was not lazy, just did not think of everything at that time. just trying to give from my experience, get more than one opinion. on your advice... I agree 100 % did not mean to give the impression you were in any way lazy.

 

Do you happen to have the paperwork for the rebuild? Seems very odd that they would not replace the gear while doing the inframe, especially since its already apart.