Front/Rear 4WD Gear Ratio - Ford 1620

jdfire · Jul 7, 2009

irwin said:
Using that vital information I was able to replace my turf tires with R4's.
turf = 13.6-16 and 25x8.50-14, R4's = 12.4-16 and 23x8.50-14.
So I ended up with a positive front wheel lead of 1.4%. This worked out great at the time. I was able to use my existing rims.

Good Morning Irwin,

I have read and reread your thread a few times during this process and found it very helpful. Ultimately I may switch to the same tires you used but right now it is a cost issue so I am just going to replace the fronts.

I was hoping to use R-4s for the extra load capacity when using the FEL. PHIL850 did the same thing here, replacing just the fronts with 25x8.50-14 R-4s, with good success. I used the gear ratio you supplied for a quick reference before calculating mine and with either number I just wasn't comfortable with the increase in lead. If I switched to the 23x8.50-14's you used without switching the rears it created a lag situation.

So, I decided to stick with turfs for now. Hard to beat $88 delivered for the pair! The new tires should be here today. My biggest frustration in all of this is the inability to get technical information from the dealer or manufacturer.

Have a great day everyone.

irwin · Jul 7, 2009

art said:
This would not be true on soft or tilled soils where the industrial would be able to sink in enough to get to the tire carcuss.

And the only time we should use 4WD is in soft earth..or.. when the rears are slipping, JMHO

I know others use frt wheel assist all the time, and if that works for them fine. It's just that I've read about many front axle failures while in MFWD..but very few rear axle failures in MFWD or in 2WD. (it happens, but it's rare) I don't think I've read about any front axle failures on a 4WD machine while out of 4WD.
Having said that..it's a machine, and overloading the front axles can cause breakage in or out of 4WD. However you use it..have fun and stay safe.

jdfire · Jul 7, 2009

My new tires came in this morning, got them mounted this afternoon. Bought them from Nebraskatire.com, $88 for the pair, delivered. They are blemished/buffed Titan turf tires. After getting them mounted I noticed that they are 6 ply, not 4 ply like I was expecting. BONUS!!

Checked Titan's website and the rolling circumference is the same as the 4 plys. So, all in all, I'm pretty happy with them. Would still like more aggressive tires in the future ... maybe on a new tractor?

billfires · Jul 14, 2009

Jdfire, I have a NH1920 and wanted R-4 tires but this tractor never had them as an option. The original tires are 27x8.50-15 and 18.4-16.1 turfs. The R-1 tire option was 8-16 and 14.9-24 ags. I found 14.9 R-4s and 13-24 rims for the rear but could not find 16.5 rims for the front (to use 10-16.5 tires). I will use 31x10.50-15 tires on the original 15 inch rims. I could not find R-4s in this size so I will use a mud tire instead. Bill C

jdfire · Jul 15, 2009

Good Morning Bill,

My 1620 didn't have an R-4 option listed when it sold either, just turfs or ags. But, as all these threads have shown, as long as you maintain the correct front/rear ratio you can mount anything you want. Good luck with your new tires!

K8vf · Feb 13, 2019

billfires said:
Jdfire, I have a NH1920 and wanted R-4 tires but this tractor never had them as an option. The original tires are 27x8.50-15 and 18.4-16.1 turfs. The R-1 tire option was 8-16 and 14.9-24 ags. I found 14.9 R-4s and 13-24 rims for the rear but could not find 16.5 rims for the front (to use 10-16.5 tires). I will use 31x10.50-15 tires on the original 15 inch rims. I could not find R-4s in this size so I will use a mud tire instead. Bill C

It turns out that titan TIRE sells the ag tire which is the SAME SIZE as the rear turf tire, and fits the 16.1 rim. All numbers the same. For the fronts, no ag tires but the turfs are 27x8.50x15 and you can buy a TITAN Industrial tire the same size!!!!!! No new rims. Of course industrials dont have a deep tread, but only 17/32 or so but I am thinking of going this way. I will check with N.H. dealer on getting them for me, since they will have to install, plus I want some service that I do not want to do, but this may be the solution for others as well. http://www.titanstore.com/info/48D890 not advertising, just a sample http://www.titanstore.com/info/412339

Yes. I know it is an old post , but these are tires for the N.H. which were not available back then...they are now.