Got a Fuso. It was sweet. Then it broke.
- Thread starter ctane
- Start date
gait
Explorer
just a thought .... are all the tyres the same size / warn by same amount? Or was the snow soft enough but became packed under the wheels. It occurs to me that the hubs and diff may have been functioning as designed but different rotation between front and rear surfaced at the weakest point. Wound the drive system up until it blew.
hubs definitely were not functioning as designed. If they had been I would have been able to disconnect from a blown front diff by un-locking my hubs and shifting transfer case to 2hi. Since Tcase was shifting properly but hubs were not un-locking I couldn't dis-engage my lunched front diff and was forced to bend over for a tow 
. Diff has been at the shop since last Tuesday still awaiting their attention
. Diff has been at the shop since last Tuesday still awaiting their attentionUpdate/new question... I just measured the diameter of my front tires Vs. my rear tires. The PO had a different tire mounted up front than in the back and even though they're all labeled 285 85R16 the fronts measure 31.5 and the rears measure 30. I wasn't wildly precise w/ my measuring so for the sake of discussion lets call it 1.25" difference in tire diameter between front axle and rear axle. Would that be sufficient difference to cause issues? If so would it have caused binding in the T-case before the Front diff? Does it make sense to attribute the failure of my ring and pinion in the front Diff to this tire size mis-match? It seems like a lot to me, I feel pretty silly for not thinking to actually measure circumference or diameter of the tires earlier given that I was aware they were obviously really different tires and had experienced this catastrophic gear failure. I had looked to see that they were the same listed size but obv. that doesn't necessarily mean anything.
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Aussie Iron
Explorer
It would only be a problem on hard surfaces and yes it would cause some binding in the transfer case making it hard to shift from 4WD to 2WD. I wouldn't care to say that is the reason to cause a front diff failure. In reality in a 4WD situation it is ideal to have more pull on the front wheels. I believe some Jeeps have a higher diff ratio in their front diff. Even air pressure can vary your circumference so that comes into play as well. Same tyre size in different brands will certainly give a better chance of different circumference.
I know not much help, forget the problem and make sure everything is right and go and enjoy your Canter.
Dan.
I know not much help, forget the problem and make sure everything is right and go and enjoy your Canter.
Dan.
gait
Explorer
the 1.5" difference in diameter (31.5 - 30) is nearly 5" in circumference. That's almost 5" difference in forward travel every revolution. Which would need lots of wheel slip to not result in transmission wind up.
Depends on what the snow was like whether the wheels would slip or transmission bind. Huge difference between wet slushy snow and crisp dry snow that compacts and would limit slip. Even on a gravel road that's a lot of slip.
Its quite possible that all gears in the transmission were stressed and hot. Just that the front diff failed first.
I would at least have a look at the oil in gearbox, transfer box, and rear diff.
Depends on what the snow was like whether the wheels would slip or transmission bind. Huge difference between wet slushy snow and crisp dry snow that compacts and would limit slip. Even on a gravel road that's a lot of slip.
Its quite possible that all gears in the transmission were stressed and hot. Just that the front diff failed first.
I would at least have a look at the oil in gearbox, transfer box, and rear diff.
Thanks for the input. Aussie Iron, I'll put it behind me and enjoy my canter when I get my differential back! still waiting on parts. Also I don't want to blow up another one so understanding why this happened is important to me. If the tires were the cause which sounds more and more likely, then I'll be sure and not run in 4x4 at all until I get some new rubber under this thing.
I changed fluid in the transmission and rear diff right after this happened, before leaving Wyoming. The rear diff fluid seemed clean and the transmission fluid had some shavings on the magnet but no chunks. I just re-did the transmission fluid(just couldn't remember if I had been able to find GL-4 or had gone w/ a dual rated fluid and wanted to replace with GL-4 since it sounds like syncros are a weak point in these) yesterday as well as the transfer case fluid. T-case fluid looked a bit heated and there were some fines on the magnet but nothing chunky. Very little play on front output while T-case is engaged so hopefully all is OK in there.
I changed fluid in the transmission and rear diff right after this happened, before leaving Wyoming. The rear diff fluid seemed clean and the transmission fluid had some shavings on the magnet but no chunks. I just re-did the transmission fluid(just couldn't remember if I had been able to find GL-4 or had gone w/ a dual rated fluid and wanted to replace with GL-4 since it sounds like syncros are a weak point in these) yesterday as well as the transfer case fluid. T-case fluid looked a bit heated and there were some fines on the magnet but nothing chunky. Very little play on front output while T-case is engaged so hopefully all is OK in there.
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Aussie Iron
Explorer
Some fines on the magnetic plugs is fairly normal as long as no pieces are there. Yes syncros seem to be a little bit of a problem but hasn't hit me yet. The idea of keeping good oil and replacing every so often certainly won't hurt. Rear diff oil should be suited for LSD.
Tyres - Yes they should all be the same size when running in 4WD.
Dan.