Tire size? 4wd Lead/Lag

[1720DnTennessee]

I was looking at tires on the net today and came across several posts regarding lead/lag for 4wd tractors. The PO of my tractor put 9.5 x 22 turf tires on the rear and 115/65/14 car tires on the front. The tractor orginally came with 8.33 x 22 on the rear and 5 x 14 on the front.

I haven't performed the rolling test to check the current lead/lag. Now here in lies my question. With the rear tires being 9.5 x 22 what tire size should I purchase for the front in order to have the correct lead situation? From what I understand the only way to truly determine the lead/lag is by doing the rolling test. I don't want purchase front tires only hoping they will produce the correct lead.

I have a set of 5 x 14 ag tires for the front so I could purchase 8.3 x 22 ag's for the rear but the turf tires that are on the tractor are practically new Bridgestones.

What to do?

 

[California]

There are charts online from the tire manufacturers showing rolling circumference along with the other technical specifications for each size they produce.

I would start by looking up the tires that should be on it, then finding new tires with the same proportions front/rear.

 

[SPYDERLK]

Whatever you do be sure the front tires lead - ie, try to pull the tractor faster than the rears will let it go. This assures good handling and more responsive turning because the fronts arent pushed. Customarily, the Mfg lead spec can vary from ~1% to 6%. More is better for maneuverability & handling, but is more stressful on the front drive. -- That said, our Kubot L3450 came std with so much lead that the fronts AGs were bald at 1500 hrs. The gravel on our drive is noticeably disturbed by the fronts when in 4wd. No ill effects and the tractor will turn almost exactly as sharp in 4wd as when not. That says the lead is on the high side. ... It may be over 6%. ... OTOH, The Mahindra 7520 has almost no lead [no gravel disturbance at all] and is MUCH less nimble in 4wd than 2wd.

 

[PILOON]

Have the same problem as they no longer make my rears.

Yes, front should lead the rears by about 5% as as time goes on the front wears to the point that there is no lead due to front wear.
IMHO the ultimate solution is to NEVER drive on pavement in 4WD as gravel, sand etc will allow enough slippage to pardon.

On my big 4WD truck every broken front axle was always when I forgot to uncouple the frond drive when I hit asphalt.