Hi everyone , We recenty had a middle axle differential problem of a SANY SY410 Mixer Truck (10m3) , as u can see on that picture these are the parts that were lost ;Adding to that I should informe u on the specific detail : - The Customer was quite late on the maintenance , say like 2 month late and he refused to do reducer and hydraulique maintenance , so he never did it -No Oil was Found in the bevel gear , it like it disappeared completely , also the bolts which fix the frame which hides the bevel gear have been unscrewed, but there is no trace of tools so as if it opened on its own , thus there was oil leakage -The Customer had also canceled the braking system on the left side of the middle axle differential -Very poor cleaning on the customer is done its quite dirty -No greasing whatsoever Thus I want to know what could be the root problem that could cause this problem ? -Is it manupulating and operation ? - Quality materials ? Poor cleaning and maintenance -Braking system on the axle side canceled …. ? -Etc
#107 support bearing for #106 active bevel gear self destructed because of lack if gear lube which ruined #112 driven bevel gear. Over here #106 is called a pinion gear, #107 is called pinion/nose support bearing. #112 is referred to as a ring gear. Anyhow loss of lubrication is what caused it to fail in my opinion.
I don't imagine that the ring gear looks very good either, judging by that pinion gear. What bolts are you talking about walking out?
And you know the spider gears have dug into the differential housing. So, it's probably destroyed as well.
Sany............LOL! People should quit buying that junk
I'm talking about these bolts , the nut of these botls were a bit open and there was I guess leakage , cuz when we went to the machine there was no oil at all , all of it leaked , I gues the customer continued to use the mixer , hence the middle axle differential problem
Yes and the main reason is that the nut of the botls were open so the question is what could have open these nuts , if customer did his daily maintenance and contrôle he would have seen the leakage , but he did not , now he asking for warranty cuz we couldnt justify what could have open the nuts of these botls thus no Oil in the machine , for information too this customer never changed Axle Oil now he more than 43 000 Km and 3184 Hours.
So were the bolts by the red arrows the ones that were all loose?
Yes exactly
If the bolts were not tightened properly from the start and checked during service for leaking, you got what you got, It's not uncommon even on new for those bolts to back off.
Yes but the machine was sold on 9 September 2020 , so I guess not a problem when it was still new , adding to that the last maintenance was done on 13/Novermber/2021 there were no leakage ,but the customer refused to change the axle oil , and last thing I know is this bolt backing off
Customers fault.
Yes thats what I told Him , but he is insisting that the botls are our problem as we have no clue what could have loosened the bolt he is saying that it our fault thus warranty
1st, is he running solid tires? If so are they all similar in diameter? 2nd what does the diff lock dog clutch look like? 3rd what does the inter-axle dog clutch look like. If the operator was walking machine with the diff-lock in, that would cause tremendous vibration, being on solids, that would carry through the driveline. That'll loosen up even nylocks. I don't know why people can't embrace crown-locks . The heat generated would surely loosen the grip of the lock washers. 3000 hours is a year and a half of continual single shift use. He's had at least 6 general services and 3 opportunities to drain and fill. Negligence is not a warrantable failure. Question for you to ponder. Had you serviced the axles at 3k , would you have identified the potential leak or just drain and fill? Not bashing, just asking. More and more dealers are using phone apps to document work accomplished and failures observed before becoming catastrophes. Just a little food for thought.
Hi Sir , Thank U for your very Intersting answer its quite helpful , I liked thewhat u said about maintenance as a tool to protect my company and the phrase "Negligence is not a warrantable failure." I will definetly use that haha ,I should search for the apps that u talked about When we did maintenance at 3K we did control if any drain or leak but nothing only the bolts leakage Tires are tubeless and they all have the same diameter , being tubless and walking with diff-lock in could we still consider it a root for the problem of nut loosing ? if Yes how can I prove it ? how can I prove that indeed it was an operator mistake and he forgot the diff lock In ? "2nd what does the diff lock dog clutch look like? & 3rd what does the inter-axle dog clutch look like." I will fetch for pictures for that
The blue arrow in the image is pointing at the inter-axle differential slave or power-divider lock. (Same thing different names) That piston actuates a fork which engages a dog clutch. That clutch forces rotational force down to the bull gear which drives the center axle differential
Gear grease is a leak that is hard to miss. I once lost a drain plug, and could smell it in the cab before the thing was empty.
This yellow arrow is pointing at the sliding clutch. You should be able to see how it forces power down to the bull gear.
You should see fretting / galling of the sliding surfaces, the tips of the dogs may be piened over and locked into one another. You may also see distortions along the shafts where the sliding clutch slips back n forth. You have what looks like regular automotive style axles. Don't see anything really exotic
I undestand this indeed very helpful but could you show me the parts you are talking about on this schematic the part names are so much different on the book
I really can't make any sense of your exploded view. It won't enlarge properly for me.
I hope this helps
So- it looks like this is just a standard truck axle- in a mixer truck. Truck was new in sept 2020, has 43,000km and 3180 hours on it. It sounds like you are the dealer that sold them the truck? 3rd member stud nuts have walked loose, all the gear oil leaked out, and now you've got a trashed 3rd member. Customer says its warranty, you're looking for a way its not warranty due to abuse/ neglect etc. Its the customers job to ensure fluids in everything, but I'm sure he's not happy about 3rd member studs being loose and walking out- allowing all the gear oil out. I have no idea what kind of warranty Sany has on their trucks, is there factory support? If its a one year warranty on the truck, you're past that. If its a three year powertrain warranty, I'm thinking you guys are putting in a third member for him- and hope the housing is okay. I'd be looking at the axles and the wheel bearings pretty close if its been run without oil very long.
Looking at the original post again, you also mentioned having a brake canceled. What is the root cause of the brake failure. Some brakes, when set, apply the diff-lock for additional holding power without introducing extra parking brake chambers. Please clarify
Other than regular service intervals, greasing and checking fluid levels, Eaton & Rockwell both recommend changing transmission and rear drive axle fluids at 250,000 miles. 43KM isn't much for fluid change. But if truck was sold and service intervals not followed? Had the truck been serviced and documented each service the leak would have been detected and repairs made before it self destructed from lack of oil. YOU CAN"T WARRANTY STUPIDITY. you can't warranty stupidity.
Hope now it ok
This is exactly my argument and what I said , but the problem is that the customer told us that it is possible that there was a 100% oil leak on the same day and therefore nothing to do with the intervals maintenance, I explained to him that it is not possible to have a total leak the same day since it was small leak from looded nuts of bolts , he does do not listen to that and asked me to give him some proof that the leak was not 100% on the same day cuz he is saying that he do daily maintenance everyday and did not see any leakage, I think he is lying and gottta find out how to prove it
Ok I will try to study this
We gave customer 2 years warranty , and SANY is insisting that its customer problem but not giving much arguments
Well the customer did not give us much information about it ,he only told us that the brake problem was canceled way before and had nothing to do with what happened , I suspect that this also could be the source of the problem
You , being the dealer need to look at the air schematics as it relates to brakes and diff-lock. You have to determine what happened with the brakes, what failed. Then you need to determine if that had any bearing on whether or not the diff-lock is affected by the brake failure. 100% oil leak of gear lube in one day is unlikely, especially considering it's trying to wick past studs and nuts. If the owner claims that, he is acknowledging that he knowingly operated the machine without oil. Leak or not, you don't operate with no lube.
Tell the customer to take it up with Sany
Well, no matter how hard I try to understand the schematic of the book, I can't identify the parts, so I have taken pictures of all the parts, I'll share them with you.
I guess this is the reducer
This must be dif lock
And this must be Differential
Here is everything I have Hope u can Help me with all that
Yeah, red = differential light blue = power divider Silver = inter-axle differential.
Are u talking about this picture ?
Mister funwithfuel what do u think of the picture I sent u above for the damages ?
I'm gonna defer to truckshop and DMiller . I see some bad ju-ju going on in the back case of the power divider as if the bull gear support bearing failed, but I see no pocket for it. And yes a pressure lubed carrier will dump oil quick if it finds an exit path.
Would u mind explain to me what this could mean ?
This image here says the pinion bearing was being thrust forward against the inner case. That tells me someone may have been spinning wheels and caught traction which could have/ would have grenaded the pocket bearing throwing the pinion forward.
Thank u sir , but what do u mean by "caught traction" I mean how could spinning wheels cause damage ?
By spinning wheel do u mean this ?
It's not the spinning, it's the sudden stop. Rotating mass, diveshafts, crown wheels, differential assemblies. All that weight spinning fiercely then something catches traction somewhere. All that energy has to go somewhere.
Yes, and that hurt to listen to. The sad thing is, that driver probably thinks he's a good driver.
So its both spinning and sundden stop that could cause the problem
The customer have very young drivers
BTW he told me no greasing cuz he have this problem on the pictue, truck always come to this area that is always filled with water , his excuse is that water remove grease as the truck is always like this in immersed in water ,But I feel in my gut this is also a root to the differential problem I just dont know how to prove it
This has got to be the craziest excuse I have ever heard of. And I have been told some pretty crazy stuff.
I would tell this customer to go find another shop. You cannot stay in business with this type of customer.
I agree with the statements above. I / we can't talk you through failure analysis on a dealer level without being in front of it. I think your best option is to reach out to Sany's tech support team and ask for assistance.
Welll this tough part , SANY only told me customer fault and thats it , and my Boss told we shouldnt lose customer he must understand thats his fault and not our , the"he must undestand" is the main problem cuz the customer is always asking "WHY THE BOLTS WERE LOOSE " he is still saying design flaw , and I still cannot prove how they were loose. its like a police detective job haha u got someone lying u gotta find a way so he can see that we know the the logical truth as for Sany they didnt give much help
But I do know that they dont have a good Driver so I guess I will just tell that the driver could have changed the gears in a very bad way or maybe the spinnning and sudden brake ... Things like that what do u think ?
In fact I have a theory I want u to know if u agree with me , the customer did not change the differential oil in time , of course this could have damaged bearings thus this picture and this finnaly caused vibration that caused the bolts to loose and oil leakage what do u think about that ?
First, I would ask Sany, "why did the bolts come loose?" Then I would calmly explain to the customer, we went to negotiations with Sany for you, they are denying warranty. It's up to your employer if they want to step up and contribute towards a replacement. Good luck
Well SANY they just say vibration and thats it they said its a commun thing to happpen which is a very bad answer saying it like that , no logical arguments just a theory summarized in one small phrase
All I can say is that to me it has a couple reasons for it getting this bad. It comes down to the old question of "Which came first? The chicken or the egg!" In other words: Did the lack of maintenance cause the bearing failure and that cause the vibration that loosened the bolts/nuts causing the leak? Or did a combination of driver abuse damage a bearing and the operator not being aware of what was happening allow it to get this bad? Hard for me to believe that even in the wet and muddy conditions this truck works that someone doing a basic walk around inspection could not have seen there was a leak from those loose bolts.
Well I will give both reasons cuz either way are customer's fault
I guessing operators can be the same all over the world. Over the years I have know more than a few who I swear you could lock in a padded cell buck naked with an anvil and by the time you let them out in the morning all that would be left is a pile of iron dust in the middle of the floor! And the guy he worked for that you sold the anvil to would want it replaced under warranty!