i hope i am in the right area here. i am new to this. can anyone guide me? my 2006 polaris trail boss 330 is making a grinding noise when under load. sounds like a chain or gears slipping. the drive chain seems fine. clutch belt ok. is there a chain in the gear box, and if so, can it be adjusted? oil level good. can i drain the gear oil and take off the gear box cover and see for myself? have not had much experiance with newer polaris atv's. thanks for any guidance at all. ron

 

Sounds like the common problem of the internal "silent chain" in the transmission jumping teeth if the drive sprockets and chain are ok(no missing, worn teeth,chain too loose,etc!) The internal chain gets stretched over a period of time from pulling heavy loads, not keeping the drive chain adjusted properly,hill jumping,etc. Some never have problems others do,just depends on how its treated.Plus with no low gear,it does put a strain on the transmission if used under loads. There is no adjustment on this chain,the trans has to be split and a new chain installed. Cost of chain is around $40,its just the labor involved in pulling the trans,tear down and reassembly. The more you can do yourself will save $$. OPT

 

thanks for the help. it turns out, upon further inspection, that my front sprocket was shot! drive chain was stretched and the teeth were destroyed on the sprocket. i dont no how i didnt see it before. anyway, new chain and sprocket, 120.00. did the work myself. i am happy. just got to do a better job of keepin the chain adjusted properly. love this website though. thanks again!

 

120$ is less frustrating than having to tear into the transmission! Just keep the chain adjusted and lubed,check after first couple rides as the new chain will stretch and need to be adjusted. Keep about 3/8-1/2" slack in the middle of the chain. OPT