R4's on a ~3,500lb tractor with loader... What tire pressure are you running?

[jcri]

I had a new set of R4's installed on my tractor yesterday... I checked the pressure after the guy left and the fronts were around 75psi and the rears were around 20psi. I adjusted the fronts to 65, the max psi listed on the sidewall was 75.

I adjusted the rears to 12psi. I was thinking that getting the pressure down to where the tire contact area is as flat as possible, without getting sidewall bulging is the goal... but just not sure.

How does everyone address tire pressure on these type of tires/equipment?

 

[Oaktree]

I'd be interested in this too.
I'm currently running 20 in the (filled) rears, and 25-30 in the front. My owner's manual only gives pressures for R1's.

 

[Texasmark]

You did what I would do on getting the tread flat on the ground. I run as low as possible to aid in some kind of reasonable ride considering my back is worth more to me than any piece of equipment. I have no radials but usually have bulges on the sidewalls of my bias tires on all of my equipment and in the case of my 6530 when running hay bales on the FEL, the fronts may pooch out even more. No biggie.

Problems doing what you are doing COULD be tire slipping on the wheel under high traction conditions or under adverse conditions, especially with fluid filled tires run at very low pressures (less than 10 psig) tire coming off the wheel, not completely off, just will disconnect from the wheel and let the air and fluid out.....my experiences on the 2400.

 

[Fallon]

I subscribe to the same theory as Texasmark. On concrete, the outside of the tread bars should barely be touching. That gives you good traction, tire wear & carrying capacity. Lower pressure means more traction at the cost of increased wear & less carying capacity.

No clue what my tire pressure is as I havent checked it in ages. But I keep an eye on the tread contact area every use. Occasionally check the fronts for excessive sidewall bulge with a load in the bucket.

Over inflation gives you better fuel mileage, but that's rarely a goal of tractor use.

 

[AWSubie]

When using the loader I put in maximum pressure which is what the operators manual suggests.

 

[Wolfy]

I do the maintenance on my dads L3710, I run them at 15 to 20 lbs

 

[s219]

Owner's manual on my tractor says to run the tires at the max sidewall pressure.

 

[LouNY]

The only time I'd consider running a tire at max sidewall pressure is if that tire is loaded to it's maximum load.
on our rear tires (all R1's) we try to keep at least 3 lugs in contact with the ground, the larger ones 42's and such will have 4 lugs much of the time.
At max sidewall pressure the tires are bowed and just the center is on the ground.
We also will vary the tire pressure at times to get the proper lead in the front axle.
My 18.4-30's are at 12 psi.

 

[Nacademus]

My Carlisle Trac Chief have a max pressure of 22psi.

They are size: 18 x 8.50 - 10 . 4ply
Model: 51S311

I run at 19. Thats what the dealer set them at so I keep them there.

I did experience a tire malfunction, though it is believed to be a manufacturer defect.

 

[Texasmark]

We also will vary the tire pressure at times to get the proper lead in the front axle.

Lou,
I think you are referring to matching gear ratios here. If so, would you mind explaining your process for the rest of us 4wd folks. In another post I was talking about determining which axle should be pushing/pulling for best tire/gear train longevity and I selected the rear pushing the front rather than the front having to pull the rear if/when unequal.

Thanks