Wheel bolts on 3320

[OldNOrnery]

Hi, all. I'm looking for wisdom and guidance here, since I've got a problem: the wheel bolts are repeatedly loosening on both front wheels of my JD 3320 and once on one of the rear wheels. The tractor is used with a flail mower, moving soil and gravel, harrowing and box scraping. I've had the tractor 10 years, bought used as a lease return with 300 hrs. We have 960 hours on the tractor now. At my purchase, the wheels were adjusted to the wide position for stability on slopes and AgTrac tires installed on all 4 wheels. Wheelbolts have been checked annually during periodic on site servicing. They still loosen, obviously NOT maintaining torque. I think we went wrong by not confirming that torque was being maintained as if we were in a new break-in period. I have the manual and just re-read it: tighten all bolts after 1 hr of operation and every 4 hrs thereafter until torque is maintained. Then every 200 hrs. This didn’t jump out at me on page 89.

Last week, my worker didn't notice until a couple of bolts pulled out of one front wheel. Not good, but thank heavens he wasn't hurt. I bought a new wheel and new front tires (it's time), and onsite tractor service will install after tapping and drilling new holes or replacing the whole knuckle (!). I need to keep the damn wheels on the tractor -- or I need a tractor that will.

So with wheels re-installed, I figure I should manage the wheels as if this is a brand new break-in period? How do I know if the torque isn't being maintained, short of a wheel bolt coming loose? I read about using Loctite. Is red Loktite 271 the best? Does anyone have a recommendation on a torque wrench? I have to improve safety and will invest in the right tools. It's safe to assume I know nothing, no bit of advice is too minor. Thanks for your suggestions.

 

[Peter 315]

Harbor freight icon 1/2 drive torque wrench for $150 is good.. Not sure I would use loctite on the bolts..

 

[beenthere]

Mark the bolts position after torquing them, and watch if they are turning with use..

Am assuming that you are putting new bolts in place each time they loosen and have confirmed the threads are okay and were not over-torqued at some earlier point and damaged the threads.

A lot of unknowns to give better answers. Sorry to hear/read of your problems.

 

[OldNOrnery]

Thanks for the help. No telling if the bolts were over-tightened but I understand the urge to do that after they get loose. I'm pretty sure at least one of on-site service guys *didn't* have a torque wrench on his trucks. The bolts were marked only on the back tires. Will do that. I didn't know that the bolts should be replaced each time they loosen. That's good info and will add to the my shopping list before the other tire is changed. Not sure the tire company has new bolts on the truck -- no more assumptions. I ordered the torque wrench with a lifetime warranty.

 

[Deere Dude]

I would make sure the wheels are sitting flat on the hub, then I would use blue LocTite 242 on every lug-bolt along with using a torque wrench.

I have a 2010 3720 that had lug-bolts loosen up on me after just a few hours. Enough that the lug bolts were badly worn. I got all new lug-bolts and re-tapped the holes. I haven't touched them since 2011 when I but the bolts on along with 4" spacers on the rears. For inspection, the lug-bolts are long enough to see them poke past the inside of the hub. I have 1200 hours on the tractor right now.

I would NOT use red Locktite because I know blue works well even for removal later. Red might be to tight, I don't know enough about that.

 

[Milo]

I used blue Locktite on mine when installing spacers and they've not loosened. I can't see any disadvantage to this on a tractor?

 

[Spindifferent]

Following. Please let us know what the eventual issue was, if determined.

On my 3520 with R4 tires and wheels, the wheel bolts were torqued and marked at 400 hours and I've now got 1100 hours on the unit. I've never rechecked the torque, but will now go out and look closely at the bolt marks to see if anything has moved.

My guesses:

Bad wheel bolts.
Bad bolt studs.
Bad stud holes in wheels.

Good luck!