something getting loose in the drivetrain

[Chamberpains]

Nilao you may want to drop the Driveline on that yoke and see if the nut can be tightened up. The yolk holds the bearing tight inside the race. Maybe a simple fix instead of rebuilding. Also if you don't use or don't need the rear rear, you can pull your rear drive shaft completely off the truck it will keep stress off that front power divider. You may get a little more use out of it before it sh1ts the bed.

Tree98 also make sure your axles are bolted tight and everything is connected on your axles. The older International used to loosen u-bolts up and allow the axle to float around causing all kinds of binding problems. Take a hammer and tap on the u-bolts you will hear a loose one really easy. And of course check any trailing arms, torsion bars, shocks, any suspension parts for worn-out or loose bushings.

[the missing link]

Yes the international were horribly for the damm u- bolts backing off , most of the time you can see them working back and forth .
You should be able to pull the plug and look at it , being a magnet plug .
And I have never done a front diff in the bush , using just my quad whinch ,lol
One trick is to get some threaded rod the same size as the bolts , use it as a guide to line everything up and to pull the diff into the housing . It may not be right be works real well .

[the missing link]

Hey chambers ,
Do you see any problem with running the power divider in all the time . I know this is a hot topic . I just like to hear other poeple thoughts on it . I have not unlocked mine in the last 3-4 months .
I have always ran mine a way more then I should . Is there any more wear because of it ? Is the wear more serious then taking a diff out premature due to shitty conditions . All winter and most of summer is shitty condions for me . I have never had a problem running them . Actally I believe I have had a lot less problems because of it .
The diff we changed in the bush was on dads truck by the way ....
I do a lot of hiway at times ,but pulling trains and winter driving . Unless it's real good out I just leave it in .

[tree98]

Chamber pains you mentioned worn suspension parts and that got me thinking (I do that occasionally) I checked it out this afternoon and found the front lower Chalmers bushings are pretty worn on both sides of the truck. You can see the arms move back and forth when you move the truck forward and back.    
What's involved in changing these?

[Rawze]

(02-26-2018 )the missing link Wrote:  Yes the international were horribly for the damm u- bolts backing off , most of the time you can see them working back and forth
....

If your referring to the u-bolts that hold the rear axle to the springs on the prostars then the u-bolts are not the actual problem. I faced this same issue with my prostar when the truck was brand new.

- The actual problem is that the carrier block that mates directly to the spring is not ground properly.

- hundreds and hundreds of pro-stars had this problem and it is so bad, you can spot it just by looking at one. The outer leaf will not be aligned to the inner one at the front of the leaf spring after they have slipped. It causes alignment issues and most mechaincs blamed it on weak and/or under-torqued u-bolts. The problem is that you can tighten the crap out of them (they are only supposed to be torqued at 600 ft-lbs max), but they keep slipping. Some shops would over-tighten them, but there has been more than a few prostars where that was done, and it caused a u-bolt failure and a wreck.

- I spoke to Eaton about this back in 2011 when mine was having this issue. They had no real answer but told me that a company in china made the components. I called a company called "Koman" over in china (yes I really did that) and found out from the guys there that it is a mis-matched carrier block. The correct solution is to remove it and re-grind it to the same curve as the spring so that it has 100% contact area and the problem would be solved. We took ours apart and this is what we found...

(Wife helping me remove carrier rear axle blocks back in 2011 when we first got our truck)...
   

(here is the actual problem).
   
In the pic above, the entire surface should have been shiny due to slippage, but as you can see, less than half the surface area was making contact under full torque of the u-bolts.

- It took us about a day or so to sand them and grind them to a matching fit. We re-installed them and torqued them to 600-ft lbs like recommended. -- To this day, we have had ZERO alignment issues or slippage problems at all. There is more than a million miles on the rears now at this joint, problem free.

- During the conversation, it was also mentioned that the blocks are supposed to be friction fitted to 100% contact area and that they should be placed so that the pins are at the center of the slot on all 4 blocks. DO NOT use the slots in the blocks for axle aliment purposes, keep them centered when installing the axles to the springs. The torque of the u-bolts is also critical for a proper allowance of "slip" for those moments when a driver slams the truck into a trailer quite hard. -- I.E., when it is set properly and there is 100% contact area like it should be, there is enough pressure for it not to slip except under extreme conditions. The slots in the block are actually for slippage (all 4 blocks = 4" of travel) if someone slams the truck into a hard stop in reverse to prevent the diff teeth from getting broken. if this happens, then the u-bolts should be replaced and the blocks set back to their center point.

In other words,.. YES, it is designed to move,... BUT it is NOT supposed to unless someone abuses the truck badly. -- the problem is that many hundreds of rears ended up on prostars without these blocks ground properly by International/Eaton when assembled.

We solved our years ago and i have seen countless prostars with this problem. There is a proper solution and it is NOT by tightening the u-bolts to the breaking/danger point. I was told of one driver that got killed because his rear axle tires "kissed" each other at highway speed after someone over-tightened these u-bolts, resulting in their failure because they could not get the rears to stop moving around.

[Chamberpains]

Tree98 I sent you a p.m. Hopefully it helps. I would post what I sent him but they're direct links to a PDF file. If anyone's curious just Google Chalmers suspension bushing replacement. You will find the first couple links will help you.

Rawze, that is some spot-on work. I was actually referring to the 90's-2000's 9200 & 9400 series but its good to see that International just never fixed that problem. The pictures you show are the exact same problem we had back then. We figured it was the paint wearing off then dirt and grime getting underneath it over time. I figured the axle manufacturers painted the axle housing before they were bolted up to the chassis which that layer of paint would get rubbed off or vibrated lose allowing the dirt and crap to get between the saddle and the axle housing. We would just clean the seats up and put new shims in and new u-bolts. That problem was the same for every saddle on the truck. Including the steering. If anyone's wondering, that big torque wrench that Rawze's wife is holding is the only and correct way to install u-bolts. It is dirty and it is a pain on top of being painful and tiring. But running a u bolt down with an impact gun will guarantee it comes loose or snaps on you somewhere down the road. They must be torqued. A decent 3/4" torque wrench can be found for $250-$300 and will pay for itself by not having to do this job over and over and over and over again because the bolts were torqued unevenly or not hard enough or better yet way too far and they snapped so you have to replace them. Spend the money and the time and it will pay you back.

[Chamberpains]

The missing link, I see a lot of problems with running the power divider locked in all the time. The biggest 1 being catastrophic failure due to losing traction and then violently getting it back especially while turning. Spin out situations, unhooking from a trailer and turning at too fast of a speed are just a couple examples. Instead of having each axle shifting power from left to right on their own terms, you now have them trying to work together while the power divider is in. That causes a lot of gear stress in the power divider or weakened components. I've replaced countless rear ends because of this. Most of which came in with the pinion shaft sheared off because of the violent power change between the axles. It wouldn't take out the power divider very often.(which you think it would being it's the smallest set of gears)

Then there are speed differentials between the two axles that can't be compensated for when the power divider is locked in.
The biggest one is mis-matched tires between the 2 axles. There is only so much backlash setting in the gears to compensate for slight differences. If the two axles have different size tires or one is new and the other is worn more. You'll get gear sets riding on the back side of the teeth or none torque side which will burn up gears in a hurry. They are out of time with each other, plain and simple.
Now, some guys can get away with this for a period of time. Because of extra slop from extra wear in gears and components or larger backlash settings. But even then your putting stress in places where its not designed to take for long periods of time. It's gonna cause some premature failure.

Picture your axles as if they were 2 brothers connected by a steel shaft to each other. They obviously will never want to or can't walk the same speed as each other. Take a second and imagine these 2 brothers tied to each other the chaos that ensues when something happens like 1 brother slips, or trips. The same thing happens with your rear ends and gear trains. You run the risk of these two brothers not getting along at some point in time for whatever reason then you will have problems. So why not let them work individually from each other as much as possible.

I think it's sheer operator laziness if you can't flip a couple switches multiple times in your day to get the job done and still get longevity out of your equipment. All you have to do is become an actual driver and assess every situation (sometimes down to a second by second basis) all day and adjust to it. Don't rely on your truck to compensate for everything. It just can't and will fail.

Now with that said, I also know that every moving operation is different. If it's in your business model or operation model to tear drivelines out to get the job done (like timbering, field harvest and any place that requires constant shi#t traction conditions, which there are better ways of getting trucks in and out of these places ie; pull trucks or equipment) then get at it. Cause there is no money in not getting the job done.

[DKenworth]

(02-24-2018 )tree98 Wrote:  It's like it isn't "catching" As soon as you roll on the accelerator after a shift. You can feel a slight clunk when it "catches" not as noticeable when the truck is loaded. All the U-joints look good. Is it common for a ring and pinion in the rear end to get worn out? or maybe something in the tranny? kenworth t-800 straight truck 265" wheelbase cm870 18 speed 46K rears

Did you check your fifthwheel play? If you pulling a trailer that could be your fifthwheel. Also if you have over a million miles check for torque rods bushings, they r probably worn out.

[tree98]

(02-27-2018 )DKenworth Wrote:  

(02-24-2018 )tree98 Wrote:  It's like it isn't "catching" As soon as you roll on the accelerator after a shift. You can feel a slight clunk when it "catches" not as noticeable when the truck is loaded. All the U-joints look good. Is it common for a ring and pinion in the rear end to get worn out? or maybe something in the tranny? kenworth t-800 straight truck 265" wheelbase cm870 18 speed 46K rears

Did you check your fifthwheel play? If you pulling a trailer that could be your fifthwheel. Also if you have over a million miles check for torque rods bushings, they r probably worn out.

It's a straight truck no fifth wheel