QUESTION: any problem adding larger front tires?

[ovrszd]

My quote about the warranty issue was based on the fact that if you've modified anything of significance on your tractor the dealer has the right/obligation to report that to the manufacturer, who could void that Serial Number's warranty. That could cause you to not get warranty coverage on an item that is not affected by tire size change. Just making the point that when you take your tractor to a dealership you risk that happening to you.

Same thing applies when you take your truck or car to the dealership if it has current warranty coverage. You can label that however you want. I think of it as the manufacturer looking for a way out of warranty service. My Sons all work at auto dealerships and see this daily. I personally saw one instance where a Ford Super Duty warranty was voided because the packaging and instructions for a programmer were found in the glove box although it wasn't installed and the truck's computer had no record of it ever being installed. Call it what you wish. the owner bought an engine. 6.0L diesel, which everyone knows has issues. Ford's loophole was what they found in the glovebox.

 

[MikePA]

Wow, very authorative answer...the only correct thing?

Asking the dealer, and the manufacturer, whether they recommend changing the front tire size is the only way to get the authoritative answer from the people who designed, made, sell and service the tractor. Obviously, they've determined what tire combinations they will sell and warrant. Just as obviously, they have better ways to spend their time than debating the topic.

As I mentioned in my second post, the OP has sufficient information to decide what he wants to do.

 

[GManBart]

Then in your experiences over the past 30 years what did you find to be the acceptable variance without damage???

My experience has mostly been in other 4WD applications. You said you didn't think I had "changed gear ratios or tire sizes in a modified vehicle of any type" and I have.

I've seen where Deere recommends 1-6%, and Firestone suggests 0-7%, and some others suggest 2-5% lead being acceptable. I guess the conservative view would be 2-5% so it's within all the common ranges suggested.

 

[GManBart]

The OP already made his decision, but Gman's going to argue it into the dirt anyway.

Time to unsubscribe from this one.

I said very early on that it wasn't worth changing (at least in my opinion). The rest has simply been a discussion of the technical aspects, not an argument. If you're not interested in the topic, there's no reason to get bent out of shape about it.

 

[GManBart]

Asking the dealer, and the manufacturer, whether they recommend changing the front tire size is the only way to get the authoritative answer from the people who designed, made, sell and service the tractor. Obviously, they've determined what tire combinations they will sell and warrant. Just as obviously, they have better ways to spend their time than debating the topic.

As I mentioned in my second post, the OP has sufficient information to decide what he wants to do.

The authoritative answer from 10 dealers who said they don't know, and can't answer the question? That's pretty funny!:laughing:

Very early on I said I didn't think the change was worth doing, but people seem interested in the technical side of it...not sure why so many folks are getting butt hurt over a technical issue....lighten up, it's just a discussion.

 

[ovrszd]

It's never just a discussion with you. Or maybe it's just the wording you use. Over and Out.

 

[GManBart]

So, after the finger pointing, people getting upset over a simple technical discussion, dealers that can't answer basic questions, and all the other histrionics, has anybody even tried to run the numbers?

Unless MF uses a transfer case with a fairly high ratio, all of their current tire combinations appear to be producing a LAG in the front tires. I'm not saying they are producing a lag, but they can't tell the OP what the mechanical ratio is, and nobody has actually measured one in the real world (at least in this thread), so nobody knows, but the math does look funny.

Using the same brand, model, and tire style, these are the numbers.

R4 10x16.5 has a Rolling Circumference of 89".
R4 14.9x24 has a Rolling Circumference of 143".

For a baseline, I'll use a very common Mechanical Ratio (1.3-1.4) to get an idea what things look like. The formula is to multiply the front tire RC by the MR, and divide that by the rear tire MR. That gives us:

89x1.4/143 = .871 That says the front tires would be lagging if the MR is less than about 1.65 or so.

What if we use that same math and look at the R1 tire option they offer?

R1 9.5x16 has an RC of 101"
R1 13.6x28 has an RC of 158"

101x1.4/158 = .894 which means the front tires would be lagging if the MR is less than about 1.6 or so.

Now, what if we got totally crazy, and substituted the larger front tires TSO was interested in?

The same make and model R4 12x16.5 has an RC of 98", so we'd get:

98x1.4/143 = .959 or a slight lag unless the MR was around 1.5 or so.

If the MR on the machine in question is actually 1.65, so that the stock 10x16.5 and 14.9x24 combo has a lead, what would the math look like?

89x1.65/143 = 1.026, or a 2.6% lead, which is right around the ideal number most people/companies cite.

What would happen if the 12x16.5 tires the OP asked about were substituted in this scenario?

98x1.65/143 = 1.13, which would be 13% lead, and higher than what normally gets recommended, but it wouldn't cause lag, which is what hurts driveline parts. Too much lead wears front tires faster, and can disturb soil excessively when turning, but it doesn't cause the gloom and doom problems everyone is afraid of.

 

[GManBart]

It's never just a discussion with you. Or maybe it's just the wording you use. Over and Out.

Oh well, I guess I'm just not for the touchy, feely types.

BTW, there is no such thing as "over and out"...it can't be both. Out.

 

[DarkBlack]

All you wanna-be mechincal engineers crack me up. 7 pages later, and not one poster showed a true understanding of the physics.
One poster was getting warrm, alluding to present tire wear and loading ,which is very relevent.

Revelation question of the day: What is the actual effective circumfrence of a high lug tire in soft land? What is it on hard land? Is it the same?
What is the effect of weight on effective tire circimfrence? Is the effetive circumfrence of a tractor front tire on soft land the same with a loader load vs empty? Hmmm...

 

[MikePA]

The authoritative answer from 10 dealers who said they don't know, and can't answer the question? That's pretty funny!:laughing:

I've spoken with about 10 different Massey dealerships, & I also called AGCO directly ... each place has said not to change the tire size...

What part of 10 dealers and the manufacturer 'said not to change the tire size' by 10 dealers and the manufacturer is not authoritative?

BTW, there is no such thing as "over and out"...it can't be both. Out.

But you're not argumentative. That's pretty funny. :laughing:

Out.

 

[Fordman1981]

My quote about the warranty issue was based on the fact that if you've modified anything of significance on your tractor the dealer has the right/obligation to report that to the manufacturer, who could void that Serial Number's warranty. That could cause you to not get warranty coverage on an item that is not affected by tire size change. Just making the point that when you take your tractor to a dealership you risk that happening to you. Same thing applies when you take your truck or car to the dealership if it has current warranty coverage. You can label that however you want. I think of it as the manufacturer looking for a way out of warranty service. My Sons all work at auto dealerships and see this daily. I personally saw one instance where a Ford Super Duty warranty was voided because the packaging and instructions for a programmer were found in the glove box although it wasn't installed and the truck's computer had no record of it ever being installed. Call it what you wish. the owner bought an engine. 6.0L diesel, which everyone knows has issues. Ford's loophole was what they found in the glovebox.

I do understand what you are saying and it isn't right when they try to get out of legitimate warranty claims. But you also have to think that some if this over reaction from the manufacturer has come from people taking advantage if warren toys. I think just because a dealer or a manufacturer is dishonest or underhanded doesn't mean we have to be as well. Now I say this because I am blessed enough to have the means to fix anything I break. And I have relationships with the dealers I buy from so they take care of me. I guess what I'm saying is if you don't have the means to fix your equipment out of pocket don't do anything that might void your warranty.

 

[ovrszd]

All you wanna-be mechincal engineers crack me up. 7 pages later, and not one poster showed a true understanding of the physics.
One poster was getting warrm, alluding to present tire wear and loading ,which is very relevent.

Revelation question of the day: What is the actual effective circumfrence of a high lug tire in soft land? What is it on hard land? Is it the same?
What is the effect of weight on effective tire circimfrence? Is the effetive circumfrence of a tractor front tire on soft land the same with a loader load vs empty? Hmmm...

All valid points. The tractor's drive ratio is constantly changing depending on conditions. And in most cases those conditions include soft terrain that allows the tires to slip enough to compensate for the ratio when it's out of the normal range. And to me, reinforce that 4wd should only be used when needed. And very cautiously when engaged on hard surfaces that don't allow the tires to easily slip.

 

[GManBart]

What part of 10 dealers and the manufacturer 'said not to change the tire size' by 10 dealers and the manufacturer is not authoritative?


But you're not argumentative. That's pretty funny. :laughing:

Out.

You left out the critical quote:

"However, none of them could tell me if there was any room in that ratio for adjustment, however small, to go up or down a tire size.

None said that there was not any room for adjustment, but they all said they did not know."

Right...they don't know, and can't answer the question. They said that in light of the fact that they offer different size rear tires, with the same fronts, and they offer two different size R1 rear tires to one R1 front tire size, both of which have different size ratios compared with the stock R4 combination. That shows you how much they understand the system....almost not at all.

The over an out comment wasn't argumentative, just a statement of fact. Richard was saying my communication style was lacking, so I wanted to make sure he didn't fall into a similar trap by using a contradictory phrase....since that sort of stuff must be important to him.

 

[ovrszd]

I do understand what you are saying and it isn't right when they try to get out of legitimate warranty claims. But you also have to think that some if this over reaction from the manufacturer has come from people taking advantage if warren toys. I think just because a dealer or a manufacturer is dishonest or underhanded doesn't mean we have to be as well. Now I say this because I am blessed enough to have the means to fix anything I break. And I have relationships with the dealers I buy from so they take care of me. I guess what I'm saying is if you don't have the means to fix your equipment out of pocket don't do anything that might void your warranty.

Yep, I agree. With Ford, if you blow your warrantied diesel truck engine the servicing shop isn't allowed to authorize the warranty fix. A factory rep is called and comes to the site to inspect the project. Including digging around in the glove box and tool box looking for anything to hang a rejection on.

I like you would rather fix my own, even if it's under warranty if the manufacturer would provide the warrantied parts. But that ain't happening. It's going to their shop or it ain't covered. Thus, be very careful about exposing the modifications you have done.

For example, I adapted John Deere rear wheel weights to my Kubota. If I break an axle, Kubota could use that as an excuse to void my warranty.

I recently made a modification to the latch pins on my FEL. I added a spring so they wouldn't jump out of the lock position. Emailed Kubota with pictures of my modification. Their answer was "that they did not condone or support this modification". Ya reckon that was their legal way out if I have a warranty issue regarding that latch system???

 

[ovrszd]

You left out the critical quote:

"However, none of them could tell me if there was any room in that ratio for adjustment, however small, to go up or down a tire size.

None said that there was not any room for adjustment, but they all said they did not know."

Right...they don't know, and can't answer the question. They said that in light of the fact that they offer different size rear tires, with the same fronts, and they offer two different size R1 rear tires to one R1 front tire size, both of which have different size ratios compared with the stock R4 combination. That shows you how much they understand the system....almost not at all.

The over an out comment wasn't argumentative, just a statement of fact. Richard was saying my communication style was lacking, so I wanted to make sure he didn't fall into a similar trap by using a contradictory phrase....since that sort of stuff must be important to him.

I finally get it. It's not that your verbage is lacking, it's that you must have the last word.

Over and Out.

 

[/pine]

All you wanna-be mechincal engineers crack me up. 7 pages later, and not one poster showed a true understanding of the physics....

IMO...This is a "crack-pot" observation...perhaps a majority of the responses were not made by those with a complete understanding of the theories behind the physics but most showed an understanding of the principals involved...your observation is condescendingly off the wall...!

 

[GManBart]

I finally get it. It's not that your verbage is lacking, it's that you must have the last word.

Over and Out.

This comment, and the last, were uncalled for, unnecessary, and insulting. There's simply no need for that, whether you like the way someone types, or what they have to say, or not.

You may have forgotten this, but this is an internet forum, and the typed word doesn't convey anywhere near as well as the spoken word. Things people type on forums might rub you the wrong way, even if there was no intent to do so. You'd be doing yourself, and everybody else, a favor by going in with the attitude that most folks here have good intentions, and if they still bother you, ignore them.

Tim (the OP) isn't likely going to change his front tires, which is something I said probably wasn't worth bothering with in the first page or so. So, nobody is telling anybody to do anything at all.

After that, this is simply a discussion about a technical issue that involves mechanics/mechanical differences, and mathematical formulas. If you're not interested in the topic, there's no need to sling insults. I'd love to see someone who's a powertrain/transmission/transfer case expert chime in, and I'd be equally interested in the opinions of anybody else who's taken a look at the math, and has thoughts on what might be involved. If you're not interested in any of that, nobody is forcing you to take part in the thread....it's really that simple.

 

[ovrszd]

GManBart, Please refer to post #75.

 

[GManBart]

GManBart, Please refer to post #75.

Kind of ironic you'd say that since you seem to be trying to have the final word.

 

[GManBart]

Deere has actually posted charts, combinations, and MFWD clutch ratios for their 7220-7520 machines....very specific, and easy to figure out acceptable tire combinations:

OMAR224650: 7220, 7320, 7420 and 7520 Tractors, Block File: OURX986_0000058_19_12MAY05.htm