My '00 Scrambler 4x4 is having some issues. Most of the time I leave it in 2x4 so I can see the roosts fly, but the problem is, every once in a while once I get the rear end spinning roughly 30 mph, one of the front tires will decide to kick in and start pulling...and I haven't touched my button. Both sides have done it to me occasionally and is not very predictable. But it is starting to upset me because I have had to replace a yoke and 2 sets of pins for the front shafts...Can somebody help me??

---------------
00 scrambler 400 4x4
98 Xplorer 400

 

When you start being concerned about how the equipment works rather than the "roosts", that would help. I suggest a shop manual and maybe a trip to talk to one of Polaris mechanics if you can't figure it out from the book. What you are doing could end up expensive to repair. If you don't know by now, there is a Heller clutch system in each hub. The axle is turning in 4x4 mode all the time - the button only energizes a magnetic coil that grabs the armature plate which drags the roller cage that rolls the pins over the hex ramp that locks the hub. With excessive rpm of the axle the roller cage must torque around to engage the pins. Eventually something expensive will brake when it snaps into lock-up and you will get a first hand education - and the chance to pay "tuition"...

Good Luck!

 

Water in the hubs or a lack of fluid in the hubs can cause the 4WD to engage when the switch is off. Take the hub off, spray everything with brake cleaner and refill with clean fluid.

 

My Scrambler had a similar problem when I first got it. I tried several things but discovering what finally fixed it was by accident. The Hillard clutch is turned by the axles and engages the hub when the rollers ride up on the ramps of what looks like a big six sided nut in the middle of it. What causes the roller to ride up is drag caused by the electromagnets in the struts acting on metallic rings that have three tabs bent up to engage the Hillard clutch. It is hard to descrie but actually simple in operation. I laid a screwdriver on one of these rings when I had them off and just by chance discovered that they stuck - the rings themselves had become magnetized. That meant that they were attracted to the electromagnet ALL THE TIME, if the magnet wasn't sticking to them, they were sticking to the magnet! It wasn't much of an attraction, but it was enough to cause the drag necessary to engage the 4x4. The good news is this - those rings were only $4 each and easy to install so it is worth $8 and a little work to try it. You may want to replace your garter spring while you are in there.

The part number for those rings is 5211148 and they are called "armature plates". You can get a free parts manual from polarisindustries.com that shows them and every other part of your 4 wheeler.

 

All the given stuff was some good info, but, if you haven't already, start with the cheap stuff first... If I were you, I would take the hub all the way apart and clean it good. Inspect all the parts for wear. Take a look at the garter spring and make sure each coil is evenly spaced and none are kinked. Inspect all the parts for wear, re-asemble to the proper torque, and add fluid. If that doesn't help, then start spending the money. It also helps ALOT if you have a repair manual. From my experience with the Polaris hubs, I found out just how finiky of a set up those things are. Reliability on them sucks BAD! The first couple years are allright, but after 4 or more years, things start to wear and p*ss you off. At least that's how my story goes.

 

Thanks for the help guys, I tore it apart, and although it did have a little water, KEP wins the diagnosis...that nice little ring was bent...$4.50 later and she's good again..thanks