Why you should change the Bull Gear on a 60 Series Detroit at 850k!

[Tosch88]

Title says it all. I had plans to take the truck in to get an overhead, mains spun in and the noise in the accessory drive looked at. I guess next week wasn't soon enough, got lucky and didn't take the motor out but still cost $4k to get fixed. Messed up every gear that the bull gear comes into contact with. It is a good week to be a truck owner. Enjoy the carnage. As a bonus its Friday and had to next day parts for Monday to have the truck back on the road by Tuesday.

[h2oskibumz]

If I'm not mistaken that's probably not the first one of these in this motor. I was under the impression that those should be changed somewhere short of 500k.

I know its bad news, but there are a couple of positives to cling to...

a) I've heard of these take out a ton of other stuff when they go... yours didn't.
b) ...and now you know what they sound like so the next time you'll know exactly what that "accessory" noise is.

[Tosch88]

Everyone I talked to including DD themselves said by 850k. I figured there was a bearing lose on the accessory drive, guess it was a little worse. Hopefully won't own this truck the next time it needs to be changed.

[h2oskibumz]

Yeah, but you MAY own another Detroit someday...

[CGT]

tell me more about this sound you were hearing??? im at about 825k on my detroit, and i hear a sound like a bearing on a belt tensioner or something going bad, but cant find anything. Is this the type of noise youre talking about?

[Tosch88]

That is the exact sound I'm talking about a bad bearing. I thought it was the a\c pump, so I replaced it (it was bad but didn't take care of the noise). I then thought it was the accessory drive unit and was scheduled to take it in next week because it was getting worse. If I were you I'd get it looked at because if they catch it early enough, its about $2600 because all that needs to be replaced is the bull gear ($700 for the gear and $1900 for labor) if not it can take all the gears out or worse the whole motor (I got extremely lucky). I new you had the 60 in your truck and that's why I posted this info.

[LBZ]

Man I hate seeing that. $4k out the door sucks.

[bayou hotshot]

I just hit 800,000 on mine last week....................cosgo take all the belts off the motor and start it if you still have a sound thats what it will be. I had a noise a few weeks ago it was just the alternator and just changed the idler tensioner pulley while i was there I like the way they taper the bearing and make you buy the whole tensioner just $120 and fixed the alternator for $180 hope thats what it is

[CGT]

bad news..... trucks running just fine, but the noise is still there. its going in the shop tomorrow to get a check up. man, im actually a little worried. i havent had to do anything to this truck in over 400k!!!! guess its time to spend some money LOL.

thanks for the heads up tosch!

[CGT]

Well, took the truck in and told them to go over it head to toe, lets do whatever needs to be done. Good news, bull gear is great, bad news, I had to replace a radiator, egr, and a bunch of filters (needed a PM anyway). I had all injectors pulled and tested, and cylinder compression tested (cost about $400 for tests??) Everything came back good with a warning about the start of low compression on one cylinder. Nothing to be alarmed about at the moment, truck is running great, injectors are perfect, oil is clean.