Green Tractor Talk banner
1 - 11 of 11 Posts

·
Registered
Joined
·
1,406 Posts
Discussion Starter · #1 ·
I have my 990 with R4 tires. The rear size is 17.5Lx24, 8 ply, max pressure 35 psi and the front are 10x16.5, 6 ply, max pressure 45 psi. I looked in the manual to see what they recommend for pressure since I was seeing the front tires squat a little and the manual says see the tires. So what I would like to know is what do you all recommend for pressure in these tires? Thanks.

P.S. the rear are not loaded. They only have air in them.
 

·
Premium Member
Joined
·
3,564 Posts
I tend to run my fronts close to max because of the loader. They are smaller tires and get a lot of weight on the with loader use.

The rears I run pretty low on air as it seems to produce more traction.

My starting point on your tractor would be 40 up front and 20 in the rear. I would see how that reacted in the soil. If this is lawn use only, I would go to 28 in the rear.

Many people do different things. I try to go for max traction in soil because that is where I use my machine. What do you use yours for?
 

·
Registered
Joined
·
2,044 Posts
I tend to run my fronts close to max because of the loader. They are smaller tires and get a lot of weight on the with loader use.

The rears I run pretty low on air as it seems to produce more traction.

My starting point on your tractor would be 40 up front and 20 in the rear. I would see how that reacted in the soil. If this is lawn use only, I would go to 28 in the rear.

Many people do different things. I try to go for max traction in soil because that is where I use my machine. What do you use yours for?

Darn, I just guessed at the pressure because as Rob pointed out, the manual for my 2520 didn't really specify a pressure. I went with 22 in the rear and 40 in the front, just about what Brian suggested. I set the pressure to that when the tractor was delivered. I've put 15 hours on it since then, and it seems to work good for general use (mowing, loader work, running a disk through the garden, etc.).
 

·
Registered
Joined
·
1,406 Posts
Discussion Starter · #4 ·
I tend to run my fronts close to max because of the loader. They are smaller tires and get a lot of weight on the with loader use.

The rears I run pretty low on air as it seems to produce more traction.

My starting point on your tractor would be 40 up front and 20 in the rear. I would see how that reacted in the soil. If this is lawn use only, I would go to 28 in the rear.

Many people do different things. I try to go for max traction in soil because that is where I use my machine. What do you use yours for?
Brian, I use mine on my wooded property with the BH digging and moving rocks etc. Today I was moving wood from an oak tree I took down trying to clear a place for a pole barn/shed which is going to be 8' x 22'. I had a load of oak on today where the 300CX FEL could only pick it up to about 56". I will post some pictures on the Compact section. What I noticed was that one of the front tires really got flexed with the weight. I hadn't checked the tire pressure since I got the 990 so I did it this afternoon and put 30 psi in the fronts and 20 psi in the backs. I will use your suggestion and put 40 psi in the fronts and leave them at 20 psi in the backs and see how that goes. I am in dirt and grass/weeds/leaves woods. I am not doing anything with lawns so no worry about tearing up lawns.

Brian thanks for the input and Andy B too.
 

·
Premium Member
Joined
·
3,564 Posts
Are you using some serious ballast with your lifting?

Mess with the rears for traction then. With r1's, I will run around 15 if I am plowing and need traction. But I normally stay around 20 for normal use.

Happy Tractoring.
 

·
Registered
Joined
·
1,406 Posts
Discussion Starter · #6 ·
Are you using some serious ballast with your lifting?

Mess with the rears for traction then. With r1's, I will run around 15 if I am plowing and need traction. But I normally stay around 20 for normal use.

Happy Tractoring.
Yes serious ballast in the fact that I got the 8B BH on which is about 2000 lbs. Otherwise I could not pick up with the FEL what I have been picking up. Last Saturday I had one rock that the FEL would not lift without a little help. I figured it was close to 2000 lbs.
 

·
Registered
Joined
·
53 Posts
Darn, I just guessed at the pressure because as Rob pointed out, the manual for my 2520 didn't really specify a pressure. I went with 22 in the rear and 40 in the front, just about what Brian suggested. I set the pressure to that when the tractor was delivered. I've put 15 hours on it since then, and it seems to work good for general use (mowing, loader work, running a disk through the garden, etc.).
The specs in my 2520 manual state for R4s 30psi R, 35psi F, and then the CX200 loader manual says add 4psi to the front when the loader is on, so your 40 is good, I run the full 30 in the rear as I have 360lbs of cast iron wheel weights & a 800lb ballast box unless i am using the 72" rake, traction is great.
 

·
Registered
Joined
·
2,044 Posts
The 2520 manual lists those specs as maximums. I didn't know exactly what that meant. What if you have the FEL off and are dragging a disc, or mowing? I found the pressure listing to be somewhat vague.
 

·
Administrator
Joined
·
22,588 Posts
I believe the intention of the manual was just a guideline and max pressures. I found my tractor rides much better while cutting the grass with the tire pressure much lower. However, when it's time to use the loader at capacity I have to increase the pressure to the max again. It's all about what your doing and if you're willing to change the pressure accordingly. You can run the maximum pressure recommended, but suffer a poor ride when not using the tractor at maximum weight capacity.

Just my .0000002 cents.:hi:
 

·
Registered
Joined
·
53 Posts
I believe the intention of the manual was just a guideline and max pressures. I found my tractor rides much better while cutting the grass with the tire pressure much lower. However, when it's time to use the loader at capacity I have to increase the pressure to the max again. It's all about what your doing and if you're willing to change the pressure accordingly. You can run the maximum pressure recommended, but suffer a poor ride when not using the tractor at maximum weight capacity.

Just my .0000002 cents.:hi:
Yes, that is correct, the actual pressure depends on use/load, grass cutting is only a small part of my uses of the 2520, I keep the tires pressured up because like I stated above, most of my work is heavy with the 61" bucket loaded to the max, or the pallet forks lifting/moving what ever, those small front R4s will squash down to much without the max 39 to 40 psi in them, even with the 800lb ballast box hanging off the rear, I just don't take the time to lower the pressure to mow my 3 acres of grass as it is all flat & pretty smooth.

But I do lower the rear pressure in the winter for snow detail when I have the bucket in the front & just a 60" blade on the rear, & with the wheel weights always on year round the traction is good in the white stuff at about 20 to 22psi in the rear R4s.:thumbup1gif:
 

·
Registered
Joined
·
6,041 Posts
I have the R4's also,and I've run 20 in the rears and 35 up front from the get go. Regardless of what I'm doing those pressures seem to be optimum for me.:thumbup1gif:


Greg
 
1 - 11 of 11 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top