Front tires caused axle failure...?

the old grind · Jul 29, 2020

Smokeydog said:
Wonder how many times the front axle oil was changed? FEL and 4wd work requires maintenance.

Finding that sand/grit (from + FEL work) had got into seals and allowed knuckle oil to leak on one side and let water in on the other (milky-looking) I learned to check all three front axle fluids semi-annually. (Center w/stick too) IMO, half an hour every six months isn't a big time commitment.

Meanwhile, .. "I'm a stay with PO neglect under-estimated", hours on the clock (if all of them), and this being a one-time thing with a more diligent owner.

Smokeydog · Jul 30, 2020

Owned several FWA ag tractors with factory FEL. All could have their wheels spaced in or out per the operating manual. Don’t recall any mention of excessive front axle wear or cautions using the FEL. Around here 3 sets of front tire replacement for one set rear is common. Imagine there is a substantial rolling circumference difference during tire wear. Again no caution in owners manual or WSM.
My poor FWA tractors spend most of their lives engaged. Life on a hillside is rough. My truck does too on the farm. From when I enter the farm to when I leave. I’ll bet I have less tire and driveline maintenance than having to constantly shift in and out 4wd when slipping. Not to mention driveway wear. In the hilly woods you slip, you slide, your stuck against a tree.
Often wanted wider front tires on the ag tractors for FEL work. Boy they could dig trenches. Miss those auto locking front axles on my current M59. Hopefully the slippery R4 tires protect my driveline ;-)
With gear and bearing damage my first focus would be to lubrication issues.

Smokeydog · Jul 30, 2020

Owned several FWA ag tractors with factory FEL. All could have their wheels spaced in or out per the operating manual. Don’t recall any mention of excessive front axle wear or cautions using the FEL. Around here 3 sets of front tire replacement for one set rear is common. Imagine there is a substantial rolling circumference difference during tire wear. Again no caution in owners manual or WSM.
My poor FWA tractors spend most of their lives engaged. Life on a hillside is rough. My truck does too on the farm. From when I enter the farm to when I leave. I’ll bet I have less tire and driveline maintenance than having to constantly shift in and out 4wd when slipping. Not to mention driveway wear. In the hilly woods you slip, you slide, your stuck against a tree.
Often wanted wider front tires on the ag tractors for FEL work. Boy they could dig trenches. Miss those auto locking front axles on my current M59. Hopefully the slippery R4 tires protect my driveline ;-)
With gear and bearing damage my first focus would be to lubrication issues.

thoner7 · Jul 30, 2020

Here's some pictures of the super bald stock tires next to the current tires.

Dropbox - condensation - Simplify your life

Yall still tho I the front tires had nothing to do with it? I was thinking it must have been the cause. Maybe by using 4x4 rarely it wouldn't be an issue, but who knows. ....

/pine · Jul 30, 2020

Doh!....Tire wear is very gradual and so would be the damage being done...without making visual inspections it (the damage) would likely go unnoticed...take a new machine with no gear wear and put worn (much smaller) tires on the front and see what happens...!!

rScotty · Jul 30, 2020

thoner7 said:
Here's some pictures of the super bald stock tires next to the current tires.

Dropbox - condensation - Simplify your life

Yall still tho I the front tires had nothing to do with it? I was thinking it must have been the cause. Maybe by using 4x4 rarely it wouldn't be an issue, but who knows. ....

Either I am missing something or you posted the wrong photo. That photo you posted shows two tires that don't look like that could be anywhere close to having the same loaded rolling circumference. Specs might be a misprint. But the loaded rolling circumference is simple enough to measure with a stretch of flat ground, piece of chalk and a tape measure. It can't be calculated from the loaded radius.
rScotty

Rancher Ed · Jul 30, 2020

thoner7,
Those 15x19.5 (R4) tires look like a great replacement for the stock 9.5x22 (R1) tires as they have the same diameter/circumference while providing a much wider footprint. With over 3,000 hours on the tractor the bearing likely failed due to age/wear which then caused the gears to fail.

Your M5400 is a (small) utility tractor, and was designed with 8-position width adjustable front rims so the tires could be set to the desired width. Setting the tires wider will increase the wear rate of the front bearings, but not to an extent I would worry about it. If this was my tractor I would fix the bear, gears, hub, etc and put the wider tire back on. I would then replace the bearing on the other side as a preventative measure and enjoy the benefits of the wider front tires.

RickB · Jul 30, 2020

Rancher Ed I agree.

sandyc · Sep 4, 2020

Have you looked at hydro pressure to make sure it wasn't raised above spec so heavier loads could be handled which in turn could cause undue wear on the front end. Make sure the rims weren't reversed cause that can change the geometry and wear stuff out too.

the old grind · Sep 4, 2020

IIRC, both front and rear wheels had been set 'wide'. While that's fine for 3PH work, IMO with as much or more FEL work being done spacing-out the rears-only is enough, and 'preferred'. (relying on the front axle & its stops for stability suggests o'loading or 'off-balance' for terrain. (xgot grapple?))

I suggest that 'sticky-outie'-offset wheels (as on boom-thumper-audio vans and 1/2-ton boggers that never see mud ...) seem to display an off-camber look by 20K mi or so. (What = that in tractor hrs, esp if 90% of seat time is muckin' stalls & movin' piles??)

Personal experience: 5+ yrs each with 2WD 'crash box' 45 HP gas & diesel ~'70 JD 1520 & '99 5210 short WB LUTs with JD 48 & Allied 495 FELs respectively. (Sold the diesel 5210/Allied 495 fall of 2019 with 36" tall 11" x 16s on 11" wide rims with std offset for the o'sized Allied. (a 395 S would have been better suited) Some of you folks have seen this shot from last year elsewhere.

repete · Sep 4, 2020

I am guessing by the picture that the center line of the wheel is well beyond the outer axle bearing putting all of the load stress on the outer bearing as opposed to sharing the load between both axle bearings. That extra width cost me thousands of dollars. Never had an issue when I put my wheels back in to the narrow position. I am sure folks will disagree but my wallet sure noticed the difference.

the old grind · Sep 4, 2020

repete said:
I am guessing by the picture that the center line of the wheel is well beyond the outer axle bearing putting all of the load stress on the outer bearing as opposed to sharing the load between both axle bearings. That extra width cost me thousands of dollars. Never had an issue when I put my wheels back in to the narrow position. I am sure folks will disagree but my wallet sure noticed the difference.

Yes, this! ^^ :thumbsup:

And it's actually more load on both bearings as say when the fulcrum isn't between them by design. (pretty universal)

It's a fundamental of load geometry that positioning/offsetting the load > the spacing of bearings will increase stress loads proportional to the ratio of those dimensions.

Oldpath05 · Sep 5, 2020

Widening the tires is a none issue if a tractor is was design for that........

ptsg · Sep 5, 2020

Oldpath05 said:
Widening the tires is a none issue if a tractor is was design for that........

Tractors weren't designed for a loader in the first place... Widening the front axle stance would be just fine is there is no loader fitted to the tractor.

Once the tractor gets a loader, you'll find your self changing hub seals quite often. No matter what brand it is.

Depending on the abuse, you can also destroy the gears on the front axle.

Egon · Sep 5, 2020

repete said:
I am guessing by the picture that the center line of the wheel is well beyond the outer axle bearing putting all of the load stress on the outer bearing as opposed to sharing the load between both axle bearings. That extra width cost me thousands of dollars. Never had an issue when I put my wheels back in to the narrow position. I am sure folks will disagree but my wallet sure noticed the difference.

Right on!

the old grind · Sep 5, 2020

Oldpath05 said:
Widening the tires is a none issue if a tractor is was design for that........
(pic worth 1000 words)

Can you find a pic of a guy mowing lawn with a toddler on his lap while you're at it?

There's another thread where I bet folks want unquestioned assurance that it's ok to do that, too.

btw, I saw a mini van yesterday whose tires were more outside the wheel wells than inside them. I couldn't get a pic of it while driving, but I'm sure that since it kept up with traffic the van was obviously designed to be shod that way.

Most 'bogger trucks' I see have wheels sticking way out, as designed, and front end parts seem to last just as long as if only driven to work.

Oldpath05 · Sep 5, 2020

ptsg said:
Tractors weren't designed for a loader in the first place... Widening the front axle stance would be just fine is there is no loader fitted to the tractor.

Once the tractor gets a loader, you'll find your self changing hub seals quite often. No matter what brand it is.

Depending on the abuse, you can also destroy the gears on the front axle.

This ain't Europe where no one is working in woods with a FEL.... SO I strongly disagree, yeah maybe 70 years ago but after that when tractor companies started put FEL on tractors they have to design the tractor for that, just like when they design wheels to reverse outward, hilly ground requires wheels to be outward so if tractor companies make it for that they better make it so it will wont fail, if it fails under designed use then they should be held liable. People need to realize,what is a tractor,,,, is for babying or is for work and work hard, but by most here, a tractor is meant to be babied, treated like eggs, if you people want to baby something then buy a Chevy...........

I for one am not going to baby a tractor, I'll work it and work it hard til its all but a bucket of bolts and that bucket of bolts or tractor will have a brand name on it when I'm done, so I'll settle for nothing less then a hard working tractor. Kubota take notice, I have a FEL with 5' bucket so if it fails to lift a bucket full of dirt over and over then Kubota has failed of being a hard working tractor, a tractor without FEL is the most useless thing there ever was unless alls you going to do is til the garden...............

So kubota take notice, heres my definition of a hard working tractor, not babying it like everyone here does, a man after mine own heart, starting>> @14:00
WICKED Grapple Testing FULL Video by Everything Attachments - YouTube

milkman636 · Sep 5, 2020

One other factor in axle bearing life is tire inflation pressure. Heavy loads travelling on over-inflated tires will pound on bearings over time. Those new tires also appear noticeably taller than the old ones. It may be good to call on a knowledgeable source to ensure correct ratios are maintained. Proper calculation, from what I recall, requires knowledge of drive ratios for each axle and the rolling circumferences of the tires. I believe the target overdrive for the front axle is somewhere in the neighborhood of 1-5%.

rScotty · Sep 5, 2020

milkman636 said:
One other factor in axle bearing life is tire inflation pressure. Heavy loads travelling on over-inflated tires will pound on bearings over time. Those new tires also appear noticeably taller than the old ones. It may be good to call on a knowledgeable source to ensure correct ratios are maintained. Proper calculation, from what I recall, requires knowledge of drive ratios for each axle and the rolling circumferences of the tires. I believe the target overdrive for the front axle is somewhere in the neighborhood of 1-5%.

Overdrive to the fronts of 1 to 5% seems about right. I've built several in that range. Changing tread just means juggling rim and tires until we get back close to the factory overdriven ratio in 4wd. In 2wd it doesn't matter.

The problem with lower percentages near 1% or eveb 05 is not that they don't work well - they do. It is that the ratio tends to get negative with tire wear, and when it goes negative you lose some steering control as the relative traction for each rear tire can steer you more than the steering wheel can compensate for. It's all a compromise.

As the front-to-rear overdrive ratio becomes more and more positive and farther away 0%, the downside is that it creates more torsional stress in the drivetrain - you'll notice that because it is harder to shift out of 4wd. To unwind the stress in the drivetrain, a tire is going to have to constantly slip. The rear tires probably won't slip, so the fronts do the slipping. That's why the fronts wear so fast in 4wd. That fast wear is actually a good thing. It means the front tires are slipping enough to protect the drivetrain.

For FEL stabiilty I haven't noticed much advantage to making the front wheels wider since the front axle tilts freely. However , there is usually a huge FEL stability advantage to widening the rear wheels since they are rigid with the frame.
rScotty