Mowing Any recommendations on tires for 770?

[Johndeere3720]

So can I put new R4s on the front and keep my existing R1s on the back? Or is that asking for trouble?

If they are the right sizes by JD's specs then yes. What you dont want is your front tires working at a different pace than the rear tires. Usually the front tires will lead by around 1.5%. So if you can find R4's that are exactly the same size as your R1's or the ones which are listed as factory size then you can do it.

 

[RoyJackson]

Here's what I have on the rear (photo attached). Firestone R1 12.4-16 in good shape. Recommendations for fronts?

As long as I'm learning, what's the difference between R1 and R4?

R-1's are agricultural tires, R-4's are industrial tires.
R-1's have deeper bars and are narrower then the R-4 tire. More traction in muddy conditions.

Per the early Deere 790 manual, you need 6.00-12 R-1 fronts to match what you have on the rear.
What you currently have on the rear is the stock size for the early production 790's, so that's what you'll want for your 770.

You don't want to mix R-1's and R-4'S.

 

[NickTaylor]

Thanks everyone for the recommendations. I'm off to find R-1s for my fronts. Thought I'd try to stick with Firestone (since that's what I have on the rears), but the data sheets on their website make it seem like they don't make any 6.0 or 7.0 tires....unless I'm missing something. Anything wrong with going with a different vendor for my fronts?

 

[RoyJackson]

Thanks everyone for the recommendations. I'm off to find R-1s for my fronts. Thought I'd try to stick with Firestone (since that's what I have on the rears), but the data sheets on their website make it seem like they don't make any 6.0 or 7.0 tires....unless I'm missing something. Anything wrong with going with a different vendor for my fronts?

Give Firestone a call first. Their website shows the most popular, but perhaps not all available tires. The site (under the Deere selection) doesn't even show the 790 or current 3005.
As far as a different manufacturer...as long as you maintain the ratio between front and rears, I can't think of any reason you can't use another brand...

 

[Villengineer]

Roy is correct, 6-12 / 12.4-16 are the correct R-1 tires for the 770. If you were closer, I would make you a deal on a fairly new set. I put R3's (turfs) on my 770 and have never switched back to the R1s, even in deep snow. Personally, the 6-12 R1's are too narrow and short to be good for almost anything that I do/will do. I've always thought the 6-12 was an odd combination for the 12.4-16 rear which is a "wide" R1 and provides pretty good floatation. NickTaylor, what wil be the primary use of your 770?

 

[NickTaylor]

I'm going to be doing mostly mowing (parts of 11 acres) often on uneven ground / slopes so traction is important to me. Also doing some FEL work (composting manure, hay,etc). I'll move the occasional round bale and box blade a 700 foot gravel drive. When I get all of that stuff done, I'll find something else to do.

 

[Villengineer]

If your mowing mostly involves a finish mower, I would suggest turfs. If you're mosty using a brush hog, I'd go for R4's. For the loader uses and with MFWD you shouldn't have any trouble box blading gravel with either R3's or R4's. The R4's will have better puncture resistance, hence why I would suggest them for brush hogging. If you are doing any "lawn" mowing, the 6-12 R1's will tear it up at every turn. I know that from experience. I rarely feel that I need any additional traction over the turfs.

 

[RoyJackson]

And it just so happens, fellow TBNer wny770 might be selling a set of R-4's including the rims.
Here's the thread:
http://www.tractorbynet.com/forums/owning-operating/202715-whats-set-r-4-tires.html

He's in NYS, but shipping costs might not be too bad...

 

[Tractor Pilot]

http://www.tractorbynet.com/forums/...ng/138670-john-deere-770-industrial-tire.html

Here is a thread that explains how some other JD770 owners switched to R4's.

 

[NickTaylor]

Wow, Lots of good input on tire sizes. Sorry to belabor the topic, but the more I look into this the more confused I get. Right now my 770 has old beat up mismatched 6.00-12's on the front. My plan was to replace them with new Carlisle 6.00-12's based on input on this site and the fact that they've been on the tractor all these years. But I pulled out the 770 Technical Manual last night (page attached) which provided the following guidance on standard tire size on page 10-10-2:

For the 770:
Front 6.50-10
Rear 12.40-16

For the 790:
Front 6.00-12
Rear 12.40-16

So that made me wonder if I've had the wrong lead percentage on this MFWD all these years. But I can't seem to find a source anywhere for the rolling circumference for any of these tires (not in the tech manual and not on any of the tire manufacturer websites that I can find).

- does anyone know where I can get rolling circumference for different sizes of tires?
- is 6.00-12 really OK for a 770, or do I need to find a source for 6.50-10's (haven't found one yet)