Ag tires vs R4

[rjkobbeman]

It's a matter of use and location. Our here in the desert (no row crops here), the R-1's are pretty useless. All you do is sink down in the soft dry sand and make ruts. The R-4's float on top of the sand and provide excellent traction.

True, the ground matters a lot.

Tall and skinny provide greater PSI on the contact patch. Tall and skinny also go through the "soft stuff" and get to the "solid stuff" underneath (if the tires are tall enough to get to the solid stuff). This is why tall and skinny work better in the snow and mud... depending how deep it is.

Fatter tires provide a greater contact patch, but has a lower PSI on that contact patch. Somtimes this is good... sometimes this is bad.

In sand (good example), there is no "getting through the soft to the solid". That is why fatties with low pressure float real good.

There are so many variables... you really have to evaluate on a case-by-case-by-use basic.

 

[TripleR]

True, the ground matters a lot.

Tall and skinny provide greater PSI on the contact patch. Tall and skinny also go through the "soft stuff" and get to the "solid stuff" underneath (if the tires are tall enough to get to the solid stuff). This is why tall and skinny work better in the snow and mud... depending how deep it is.

Fatter tires provide a greater contact patch, but has a lower PSI on that contact patch. Somtimes this is good... sometimes this is bad.

In sand (good example), there is no "getting through the soft to the solid". That is why fatties with low pressure float real good.

There are so many variables... you really have to evaluate on a case-by-case-by-use basic.

Exactly; here are two different size Ag tires, so it's hard to generalize about sinking in loose material or flotation etc.; some times the difference is almost negligible.

 

[Diamondpilot]

I keep hearing all this talk about R1's and a FEL. I have only used 1 tractor with R4's and all the rest have had R1's. All but one of the tractors I have operated were equipped with a FEL. My little Jinma 28 HP tractor has a loader on it that will easily pick up 2,200# 5' off the ground. I have also lifted a 3/4 ton Dodge Van's front end off the ground so we could drag out a rock the telephone man drove over. I only lifted the van a few inches but it was heavy. I have had no issues with my R1' tires running 32 psi. I would be more afraid lifting that type of weight breaking my front axle before it did tire damage.

Chris

 

[Scotty370]

Great conversation! I believe, I've got unloaded R-4's. That like the 'Skid-Steer' shallow bars, correct? I will say I like them, and on turf, as long as I'm not in 4WD, they don't 'scuff' and destroy! But that said, if I get into mud, they just 'load-up', and I might as well have 'racing slicks' on the back! Just another excuse to buy another tractor!!! ~Scotty

 

[foggy1111]

How do you manage a 1800lb difference???

The 790 weighs ~2100 and the 3320 is ~2900. That a diff of 800. Unless you are going to leave the loader on the 3320 and didn't have one on the 790.

But it will be a close call but my money would still be on the ag tires

The fluid in the 790 is 450 lbs less than the 3320's fluid. The cx loader and bucket weigh more than the 70 loader.....and the tractor is 900+ lbs more (the 790 only weighs 1900 lbs (I thiink) . When I did the math to write those numbers...it came out to that much difference.....but my wife cleaned my desk this afternoon....and I cant find my figures. :laughing: (Sorta like the dog ate my homework? :laughing

I'm going to look for my math and see if I can better justify what I wrote. ....But my 3320 with the loader and loaded R4's weighs in at 5000 lbs.

I have sandy soils.....so its hard to know how that will effect the R1 vs R4's too.

 

[LD1]

The fluid in the 790 is 450 lbs less than the 3320's fluid. The cx loader and bucket weigh more than the 70 loader.....and the tractor is 900+ lbs more (the 790 only weighs 1900 lbs (I thiink) . When I did the math to write those numbers...it came out to that much difference.....but my wife cleaned my desk this afternoon....and I cant find my figures. :laughing: (Sorta like the dog ate my homework? :laughing

I'm going to look for my math and see if I can better justify what I wrote. ....But my 3320 with the loader and loaded R4's weighs in at 5000 lbs.

I have sandy soils.....so its hard to know how that will effect the R1 vs R4's too.

There's only one way to find out.....

 

[Diamondpilot]

JD 790 4x4 weighs 2,105# according to the net.

Chris

 

[RoyJackson]

JD 790 4x4 weighs 2,105# according to the net.

Chris

Deere rounds that off to 2200 lbs (with R1's, I believe) in the operator's manual. They don't specify if the tires are filled, but I doubt it.
My R4's (on the 790) were 15-19.5 size, which is the same as the as most of the old 4xxx series (with R4's) as well as some of the new 3x20 series machines, so the liquid ballast should be the same (but I don't recall if foggy's 790 tires were loaded).
I do know there's a base weight difference of about 800 lbs, but 5000 lbs seems a bit heavy.
My 4400, which is quite similar to the 3320 (actually closer to the 3520 in power rating), goes about 4200-4400 lbs (including the 430 loader). That's with filled 41x14x20 R3's which are considerably taller then R4's, but not quite as wide.

 

[foggy1111]

I found my notes buried in a pile. Here's my numbers on the 3320 weight.

Tractor 2900# + 300 CX 850# + bucket 300# + ballast 850# = 4900# Field Ready (less implement)

I just found the wieght on the 70 loader to be 646 lbs...but I don't know if that includes the bucket. So....2100 tractor +646 loader +400 ballast = 3146 # including bucket??

I had the small size R1's on the 790 and the big R4's on the 3320 thus a big difference in ballast.

I rest my case.

 

[buck12]

Scientific data (aka my experience) has shown that R4s are great for every job unless it involves mud. Mud and R4s will make a preacher cuss.