Hate When Pivot Shaft Breaks!! D10n

[herbsupurb]

Can't even imagine how you can break a piece of solid metal about 8 inchs in diameter, but if you ever do, this is what it would look like

 

[Dirtman2007]

My lord, that had to be an experience in it's self. Looks like it's been sitting for a while according to all the rust. Could it have been a stress crack or a weak point that failed over time?

 

[herbsupurb]

Operator was running machine and stopped after the track had fallen off of the LH side. Roller frame was rubbing up agains the sprocket teeth. No machine as operating at time of break down, the last pic was the next day after it had rained, making it turn to rust.

 

[DPete]

Looks painfull, kinda like breaking an equalizer bar on the older machines

 

[King of Obsolete]

oh my!! that is a big shaft to break. good thing you have good ground to fix it on but a little hard on the ankles after walking on it all day.

thansk
KoO
Published Author

 

[Dozer575]

Shows ya how much stress is on that part.

 

[MKTEF]

Just a smal repairjob, with pieces you can handle with musclepower.

Normal service jobs would be higher up on the ranking list..

Metal might have a small internal weakness that evolved over time.
Then one final day the weakness was so big it just broke.
I bet its designed to be strong enough, but u cant get a 100% garantie on the metal quality.:cool2

 

[cps]

Hi all, think what has happened here is the pivot bushings that the shaft runs in were left to wear for to long, and the banging about caused it to snap.

 

[CarterKraft]

We had a worn and bent shaft in a D9L on a major rebuild.

We had our machine shop metal spray it and straighten it out, looked great didn't last a 1,000 hours.

There is allot of stress at that outside bearing.

 

[JimBruce42]

Nice pics... looks expensive, where in PA is that?

 

[herbsupurb]

Near the frackville area, Northeastern region

 

[Construct'O]

It's not just the weight of the machine,but also the continued banging of the dozer blade ,since the trunion ball for the blade bolts on there also.

Driving and dozing over those rocks day in and out wouldn't have anything to do with it i'm sure.:usa

 

[JDOFMEMI]

From the looks of it, there was a good deal of wear judging by the step in the shaft near the end. The loosness in the bushing will cause additional impact, that would help to fatigue the shaft.

Not a fun job by any means. I am fortunate to not have had that problem, but D-9 and D-10's are renowned for breaking thr EQ bar. D-9R has broken 4 in 4 years, and had averaged 1 per year before I had it.

 

[nextdoor]

Does anyone know what a pivot shaft is worth? Im just curious as Im due to take the track frames off our D9L shortly to repair the cannon seals and Id like to know a worst case senario just in case ours is a bit crook too (praying that its OK!). Cheers.

 

[CarterKraft]

looks like a little over $16K,

might want to that sooner than later.

 

[Dozer575]

What it is is the sprocket is pulling up at the rear idler under a hard push, or ripping.
So that shaft is taking the weight of the machine as well as what ever it is trying to push. How many pounds of drawbar pull will a D10 put out? Divide by 2 for each side, and add machine weight and shock loads.
In another normal configuration the sprocket is pulling the track across the bottom rollers, not lifting the rear if the track frame off the ground.

 

[JDOFMEMI]

We could go on about this again, but I would rather have the pivot shaft take the abuse than the live axle on the final drives. I have not so fond memories of finals lasting 6,000 to 8,000 hrs, then needing overhauled on the D-8K and D-9H when they worked hard in a rock pile. Not to mention the cost or amount of downtime.
The current crop of D-9 hight track models consistently give me 14,000 to 16,000 hrs on powertrain components.
In my book that wins the argument hands down.

 

[cr500]

Nextdoor. If you find the pivot shaft is worn in the bearing areas, try getting it metal sprayed to build it up. Have had it done to a few 9,10 and 11s and it went well. If you do go for a new shaft, look around some of the after market places to see if you can get a solid one. The solid ones dont USUALY break, while the hollow ones do.

 

[nextdoor]

Thanks for the heads up on it cr500 but I still havent had a chance to look at it yet as my farm duties keep getting in the way! Im hoping to get out of it for 25K or less but you never know till your in there. I have to change the pivot shaft seals , cannon seals and possibly get the cannon shafts re-chromed. So Im quietly hoping that the pivot shaft is going to be OK but Murphy might put an end to that!! Cheers.

 

[surfer-joe]

I don't know if Cat still offers rebuilt pivot shafts or not. They did in the late eighties and ninety's. Some dealers offered them on their own. Advantage with them is they have a good warranty. I got mixed up with some local flame-sprayed shafts for D9L's with local machine shops. Sad experience and costly.

Most folks do not service the pivot shaft oil reservoirs properly. Yes, there is a change interval. Most folks also do not check the reservoir oils levels often enough, nor use the proper viscosity oil, which should always be an SAE 50wt. This is an expensive area not to pay attention to and as others have noted, it takes an enormous amount of abuse. Roller frames are probably one of the single least looked after parts of a dozer, yet can cost the most when they go bad.

I remember the older 8's and 9's when the finals went out. uug! The newer models are still a lot of work, but easier to remove and reinstall.