Can someone with a 5085 or similar with radials tell me the suggested tire pressures?

[sixdogs]

I put radials on my Deere 5520 which is similar to the current 5085. My Firestone radials are the equivalent to 18.4 x 30 and 12.4 by 24. If anyone has an owner's manual for a 5085 or similar could you look and tell me their suggested tire pressures?

The Firestone calculations for mine is 7 PSI for the rear tires and even at that rate I think it's too much air. On the other hand I don't want the tire to slip on the rim from too little pressure. Thank you.

 

[JD5210]

If you go to this URL it will give you access to online operators manual for the 5085m and the 5085e

John Deere Ag - New Equipment: Technical Publications - Equipment Search

 

[sixdogs]

If you go to this URL it will give you access to online operators manual for the 5085m and the 5085e

John Deere Ag - New Equipment: Technical Publications - Equipment Search

That is really a great site--thank you.

Here's the shocker to me. Based on weight, Firestone calculates my rear tire pressure to be about 7 PSI and that's with two rear weights per side and cast wheel centers. Deere suggests 30 PSI. That's really a lot and must blow those puppies up like a water slide inner tube.

For the front, they suggest 36 PSI and that's sort of in line with what I figured for loader use. Without the loader I can't recall but it seems 20 or 24 PSI should be plenty.

For the rears, 7 to 9 PSI for me doesn't put three bars on the ground as conventional wisdom suggests but maybe only two tire bars touch. Oh, well it's great to know what the Deere engineers think...they sure do put the homework into their research and I respect what they think.

Thank you again for the info...I was really stumped where to go.

 

[Tx Jim]

That is really a great site--thank you.

Here's the shocker to me. Based on weight, Firestone calculates my rear tire pressure to be about 7 PSI and that's with two rear weights per side and cast wheel centers. Deere suggests 30 PSI. That's really a lot and must blow those puppies up like a water slide inner tube.
.

Unless one has a very big load on 3 pt hitch 30 psi sounds way too high for rear radial tires

 

[sixdogs]

Unless one has a very big load on 3 pt hitch 30 psi sounds way too high for rear radial tires

Yeah, I'd need an 8,000 lb tractor with 15,000 lbs of weight. What is Deere thinking to say 30 PSI?

 

[bushhog28]

so... i have not checked my book but the numbers sound familiar. I will say that jd only sells the 5085e with bias tires. I'm not sure if that makes a difference or not.

 

[sixdogs]

I'm the OP on this. I looked up the JD info and they suggest some really high pressures such as 30 psi rear and 36 front. That is way too much.

On the Firestone website is the formula for tire pressure in a radial by using tractor weight and distribution to determine air pressure. I did the math and that calls for 7 PSI in the rear. The front has a loader at times so I figure 25 psi to 30 psi is good.

Now, the old formula for air pressure in a tire is to inflate until three tire bars contact the ground at the same time. For my radials and weight, 7 PSI is correct. Since that is pretty light and I don't want to slip a rim I went to 9 psi for the winter and will assess in the spring..