Lead Lag 4wd Tires

Mark Page · Jul 22, 2012

Thought this was rather interesting. A sure fire way to tell if you've got the right tires.

http://www.firestoneag.com/webres/File/Tire-Info/TireInfo-LeadLag.pdf

Dadof3 · Jul 22, 2012

Thanks. Great info.

SmokingLoon · Jul 22, 2012

Interesting read...now I'm going to find 2 buddies and try this

npalen · Jul 22, 2012

I'm wondering why lead is acceptable and lag is not. I can see that in a turning situation it would be better if the front tires were moving faster than the rear tires but not sure why a lag condition would put more strain on the gears than a lead condition in normal forward motion. Anyone have thoughts on this?

Just Bill · Jul 23, 2012

npalen said:
I'm wondering why lead is acceptable and lag is not. I can see that in a turning situation it would be better if the front tires were moving faster than the rear tires but not sure why a lag condition would put more strain on the gears than a lead condition in normal forward motion. Anyone have thoughts on this?

I don't know for sure but it may be the way the gears are made.
Plus a lag is actually trying to hold the tractor back instead of pulling it forward.
Lead is probably real important on a slick surface for steering control.

JerryG · Jul 23, 2012

In a lag condition, the large rear tires over power the small front tire. When that happens you can't steer the tractor. It also puts more stress on the complete front drive.

npalen · Jul 23, 2012

I tried another method of checking lead/lag using a strip of tape on each tire. I put a strip on the rear tire aligning it with some reference on the fender. Then drove one revolution on the rear tire then placed a piece of tape on the front tire at top dead center. Then backed up to the tape on the rear tire at it's reference point, engaged FWA and repeated the one revolution test. The tape on the front tire again indicated top dead center position. (to the best of my ability) This indicates to me that the front and rear tires are "in sync" with the gear ratio between front and rear.
I repeated the test a couple times to verify. This was done on wet turf so that the front tire could "slide" if it had to when FWA was engaged.

npalen · Jul 23, 2012

JerryG and Just Bill, it's making sense to me now. Really want that front end pulling instead of being pushed. An analogy might be trying to push a rope down the street?