Tire Pressure Questions

[40_acre_mule]

I've got an L4400. The manual says 20 psi for the R4 tires, but the sidewalls show much higher max pressures.

question 1...will running the tires at such low pressures make it more likely to break to bead when running over big rocks or small stumps?

question 2...what are the problems associated with running higher pressures?

 

[Tx Jim]

I've got an L4400. The manual says 20 psi for the R4 tires, but the sidewalls show much higher max pressures.

question 1...will running the tires at such low pressures make it more likely to break to bead when running over big rocks or small stumps?

question 2...what are the problems associated with running higher pressures?

20#s of air should keep tire beads seated. Higher tire pressures results in rougher ride and less traction due to "smaller tire footprint".

 

[topbuilder]

The max pressures shown are probably "while seating bead" during tire mounting. If you have ever used a tire hammer to unseat a bead you will have greater faith the bead will never unseat with 20 PSI on it.

 

[oosik]

With the grapple on the FEL I've run the front tires up to 30psi. I have the rears right around 20psi.

 

[Fallon]

Put on your average set of implements. Inflate/deflate until the tread touches the ground all the way across the width of the tire. Done.

That gives you the best traction & most even tire wear.

 

[CCWKen]

The maximum pressure on the tire is usually for obtaining the maximum load rating for the tire. If you're not any where near that load, which you probably aren't, use the pressure suggested by the OEM or use the "ground contact" method as mentioned.

 

[Fallon]

And if you pick up heavy loads on either end, you'll want more pressure than checking tread contact to avoid crushing the tires. Will result in slightly over inflated tires & increased wear in the center, but that's better than crushing the tires & blowing the bead.

 

[Gary Fowler]

And if you pick up heavy loads on either end, you'll want more pressure than checking tread contact to avoid crushing the tires. Will result in slightly over inflated tires & increased wear in the center, but that's better than crushing the tires & blowing the bead.

I believe the OP stated to put on your typical implement to obtain max weight management then inflate tires till all the bars are touching. You wont be "crushing" the tire at that point. Fronts being smaller require more air pressure than rears. 20 PSI in the rear tires would be plenty for any weight that the tractor could lift. I find that generally speaking inflating to about +or -2/3 in rear and +or-3/4 front of the max rating handles any load for tractor tires .

 

[40_acre_mule]

Thanks for the replies, y'all.
I feel smarter already.

 

[4570Man]

I put about 45 psi in the fronts and 15-20 in the back. The front tires have a slow leak and they start looking noticeable flat with no load on the loader at about 20 pounds. I don't stress non highway service tires. I usually just air them up until they don't look flat and call it good.

 

[Fallon]

I believe the OP stated to put on your typical implement to obtain max weight management then inflate tires till all the bars are touching. You wont be "crushing" the tire at that point. Fronts being smaller require more air pressure than rears. 20 PSI in the rear tires would be plenty for any weight that the tractor could lift. I find that generally speaking inflating to about +or -2/3 in rear and +or-3/4 front of the max rating handles any load for tractor tires .

The OP of the inflate/deflate until all tread touches? That was me. I was posting a followup. If you occasionally carry heavy loads inflating for your average might not be sufficient pressure to handle the max load.

 

[buickanddeere]

What is the tire size, radial or bias and how many pounds weight on the rear and front axle . There is a cross reference chart on the tire manufactures web site. I would not be surprised that 12psi is sufficient .
This is a low speed tractor tire. Not a weighted down SUV with under inflated Firestone tires on an extended 70mph interstate trip during a 90F day.

 

[oldballs]

My OE manual recommends a higher pressure on the front tires when using the FEL. Since I mount/dismount the FEL on short notice, I just leave the front tires at the max psi recommended by Kubota. It probably make the ride rougher when using the MMM, but I'm used to it and don't have to change up and down the psi. The rear tires stay at the same recommended pressure all the time.

 

[dstig1]

Because it is sooo easy to lift something heavier than you should with the FEL, I try to keep my fronts at the max tire inflation limit. Especially since they do lose a little pressure over time. I worry a lot less about the rears.

Per the direct question: the mfg of the tractor will tell you the best compromise for their typical setup (just like car makers do). The tire ratings marked on the tire will tell you what it is rated for at a couple given pressures. Your range is between what the Tractor Mfg tells you and the Max limit for the tire. If you will be loading it heavy, then go towards the max. If you are not really stressing the tractor, go towards the tractor mfg spec. Other than that, don't worry about it too much.

 

[RjCorazza]

I kept my previous L3410 pressures at 15 rear and 20 front. The L4060 was delivered with 40 psi in the fronts, which made for a harsh ride, so I compromised at 30 psi.
Kinda related, - I rolled a front tire off the rim on the L3410 during the East coast blizzard last winter. I had a slow leak, and apparently let the pressure get too low. You don't want that hassle !