You will get air in the ADC if the mechanic was in to much a hurry and let it drain versus just bleeding it. Get some ADC fluid, bleed one side until the level is almost to the bottom of the reservoir, refill it and bleed the other side. Your air should be gone. Check your front diff fluid. If it is black change it too. The worst thing about a Polaris is all the fluids it takes. Bleeding the ADC if fairly easy. Checking the front diff is hard on some models and getting the plug loosened can be rough. Takes a 8mm Allen wrench and sometimes a two foot breaker bar to get it loose. Can't hurt anything if you are turning it the right way.
Don't know why some ADCs are more touchy than others. The ADC on the 08 and newer are really great on really steep trails. Turn it off when not needed and your fluid should last a little longer.

 

I have an 07 X2 that is grinding as well. With only about 12 hours on the machine, I do not think that is right. My book does not to say to use Demand drive or angle drive LT for this, but ADC fluid. I asked my dealer and they said ADC fluid also. I asked if Polaris was having a problem with this and they said not as far as they knew. I am having trouble locating the bleeder valves. I am putting in the ADC fluid I bought. I have a book, but it does not show where they are. It just says locate and bleed.
I like very much using this feature when in hills.

 

After all this time I can't help but feel bad for everyone who has had, or is having problems with their adc front diff's. My question to Polaris is why do they keep pushing this weak link on an otherwise good machine and still say to the customers all is fine? The parts that fail aren't bearing cages or stuff like that, but they are plastic parts that wear and mess all the other internals up. Changing the final drive fluid is only a bandaid solution as I do believe there is an engineered built in life span on this part. After I added a switch to bypass the adc on oct 2007 I sold the machine, the new owner knows all that has gone wrong and keeps the switch at off and has remained trouble free. Enough time has passed to say get a switch if you don't have one and try not use adc unless you really have to.

 

As some of you know,i had this recent problem of putting in the regular stuff and have it start grinding immediatly.Changed to the new plus and problem solved.Oil even feels different in your fingers
UPDATE I stopped at the dealer i bought my quad at while on vacation,and told the head mechanic of my wrong oil problem.The dealers have an update from POLARIS[because of problems] the new reccomended oil change for adc units IS 20 HOURS I read it with my own eyes.

 

is there alot of crap in the ADC from break in??

 

I didnt notice [didnt pay attention]alot in mine ,i just changed it the first time this spring,bike was 1 year old[07 but was a left over model].MY thoughts are that any gear box ,or tranny will have a few filings in them at first ,until the gears wear into each other,Iknow my KUBOTA tractor transmition had filings in the screen on the first time.Most do im told.Iwouldnt think normal break in on a gear box would be much different.
The fill plugs are a bear to get out ,on all my familys sportsmans[3] i weld a nut on the end to make it easier next time...simple mod that makes life easier.

 

I bought a 08 800 with 8 hours on it and have had nothing but problems. The first problem was the starter bendix had to be replaced within 60 some hours, then the ADC within 90 some hours started making the grinding noise. The polaris tech couldnt believe it. He changed the fluid and it sounded better, but when he called polaris they told him that more than likely the two clutches were shot and the price on those are 300 a piece. I didnt understand this the ADC has only been in and out a few times. Now with 104 hours the transmission has a bunch of slop in it. I was pulling a little har around the drive and thought the tranny was going to fall out. Havent had it looked at yet, but i think it maybe time to trade.

 

I've just got back from my first familiarization ride on my new 550efi X2 and thought I'd investigate if the 'clonking' noise heard when descending a hill with ADC on was normal or a problem.

And I'm a bit depressed to find that similar ADC problem appear to be quite common. Ho Humm!

The 'clonking' noise is directly related to the speed of descent. For example a speed of 3mph would give a 'clonk' every 1/4 a second or so. The sound I'm getting is not really a grinding noise but I guess if you descended a hill at a higher speed the individual 'clonks' would blur to become a grinding noise but I think it would most likely sound more like the noise a car's ABS makes when it activates. A sort of a vibration with a buzzing noise.

To make matters more difficult my supplying dealer is many miles away and the dealership network here in the UK is not as widespread or mature as the US.

So I was wondering if I could ask if anyone from the US of A (and home of Polaris) could offer any advice or information as to whether or not my X2 has got one of the common problem or is this something different and what I should do next!

All information and advice gratefully received by this worried Polaris noob from over the pond.

Many Thanks.

Kevin.

 

Disconnect it like I did and don't worry about it any more. It's the wire that goes to pin 11 on the ECU (on an 800 anyway). I encounter plenty of steep hills riding transmission lines here in western NL and rear only engine braking hasn't been a problem so far. For the life of me I don't know why they don't just drop the AWD system and come out with a normal 4x4 system with a locker (probably because a proper differential is more expensive to manufacture). It's not as difficult to push two buttons as they make it out to be in the promo videos...