Looking for tire advice for Deere 770

[Jaygyver]

In the for what it's worth category of replies, I have a JD 2320 equipped with R4's. Although they work fine for me for most of my needs around the house and in the woods, I soon learned they were helpless on ice or hard packed snow. After some research, I bought a tire groover and grooved the center of the lugs on the R4's. What a difference! Traction on ice and hard packed snow was vastly improved.

You know, if the lugs on the R-4's were a bit deeper I think that would help, at least until they got worn. Maybe I'll try the tire groover, $1500 a couple years ago to switch wheels/tires can wait a bit more.

 

[LouNY]

All of the major and even many of the smaller tire manufactures will have specification sheets for their tires. Those will list the O.D. of the tire and much more info on the tires. Even within the same manufacturer all of the different models of there tire will have different dimensions with the same listed size. One of the important measurement will be loaded rolling circumference, or loaded radius which are the important numbers. I have seen more then 8 inches difference in rolling circumference for the same nominal size in the different series of R1 tires they offer.

 

[evan waa]

You should get the mechanical ratio between the front and rear axles. Then even though the tire number sizes may be the same. The rolling circumference of tires varies with number of lugs and number of plies and manufacture of the tire at the factory rated pressure. You would probably want about a 2 to 3 % pull 5 % is high

 

[NickTaylor]

Ok I have dug around a million tire websites, called the dealer and visited the local ag tire shop. Was hoping for a hybrid tire, but there just isn’t much available for little tractors like the 770. Very few R-1 setups I could find that support the needed MFWD 1-4% lead. Closest I could find was BKT TR-171 for front (25.0 diam, rolling circ 76.9) and TR-135 for rear (diam 37.8, rolling circ 112.3). By diameters, the lead is 1.04, by rolling circ the lead is 1.07.

Anyone have experience either these BKTs? Too aggressive for mowing hilly pastures and trails? Too much lead?

Interested in any other available combos people have recently installed?

 

[Jaygyver]

I got my front tires from Amazon and I believe they were also listed as for Kabota and a couple of others so I would try to find another tractor brand with similar size front/rear tires and go from there. Find the tractor that has the same size ratio and find that tractor brand's R-14 tire/rim combo? (They do list a Kabota 7100 as having the same tires but if you look up its spec sheet it shows it has 6-12 NOT 6.00-12, so much for that.)

There's very little information on our JD 770's out there for some reason. I guess we got the perfect tractors?

Again, I was at least 10 years past changing my front tires and haven't had any issues, as of yet anyway. Either way you go just use the 4x when you need it and being in the dirt shouldn't be an issue when you do use it. We are not doing 70+ mph/kp or pulling 8 plows behind us to worry too much about it. There has to be a little bit of leeway to account for wear, like in my instance of bald front tires and 50+% rear tires.

The R-1 front tires I got, the brand is Max-Auto and they are 6.00-12.
I couldn't find the R-1 6.00-12 MaxAuto on amazon now, only the 6-12, but there are a couple of other brands it seems but they just list the tire size and not tractor brand fitment. Maybe on their own website. They were one of only a couple outfits that actually had a warning stating that 6.00-12 and 6-12 were different sizes.

 

[jyoutz]

It really sounds like all of your tractor uses would be best suited with traditional R4 tires. If you are not doing any serious ground-engaging work that requires the most traction, then R1 tires may not be the best choice. Seems like you already know this...

That said, I just replaced the R4s on my 20-year-old JD 3520 (tires starting to dry-rot) with the following on the front: Carlstar Trac Chief 6 ply, and Carlstar Ground Force 400 R4 14 ply G rating on the rear. All have great reviews, and I've been happy with them so far for the same uses as you. I've also used them for tilling with my reverse-rotation tiller and they have better traction than the original Galaxy R4s. Most of my tractor use is bush hogging and loader work.

No experience with the R14s, and they look interesting, but wonder why you think you need them based on what you use the tractor to do. If the majority of time on your tractor was tilling, discing, plowing, chiseling (working the ground), with a little bit of the bush hogging and loader work, then traditional R1s would likely be best.

My opinion is to look for the highest-quality R4s you can afford. Titan, Galaxy, Goodyear, Calstar all have lots of models and sizes. BUT, this may well require different rim sizes for the R4s.

My biggest issues with the new tires were actually finding a reseller that had my sizes in stock, and then finding someone to install the new tires. And, there was the cost of it all...

Good luck with whatever you decide!

Agree. For what the OP is doing the R4 tires have the stiffest, toughest sidewalls.

 

[jyoutz]

You know, if the lugs on the R-4's were a bit deeper I think that would help, at least until they got worn. Maybe I'll try the tire groover, $1500 a couple years ago to switch wheels/tires can wait a bit more.

The new Kubota R4 tires are grooved. Maybe check those out.

 

[kenacp]

Will have to replace my original 770 tires before too long. Keep posting the options.

 

[jyoutz]

Will have to replace my original 770 tires before too long. Keep posting the options.

The options are going to be based on your wheel sizes. Can’t change to R1 tires if you have R4 tires/wheels now. And vice versa.