Fenix gear diff issues

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  • Quote: A little patience and some common sense goes a long way. And you don't have to be a photographer to see that those pictures are useless.
    Also how would a picture ever show an out of round shaft in the first place, they were sent more pictures than that but he only chose to use the ones he had me send to his email.
    I did indeed send additional video and pictures to the fenix sites email. But he refused to get them sent to over.

    Also I posted a very clear video on the fenix face book page, I wish he would have posted that.

    I know some of you will hinge over the quality of a picture, I however maintain that better customer service and over all quality are the real issues here.

    Also, they just now replied to me on Facebook that the issue is being handled, better late than never.
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  • Hi Fenix guys,

    This isn't a quality problem, but just wanting to get advice on maintenance.

    The gear diff is working great. I did have to put a spacer between the spring and cap. The hex with the set screw would slide all the way to the end (closest to the upright) and allow the wheel hex adapter about 3mm of play. Did anyone else run into this?

    The main question is how to keep the oil from leaking when not racing. Or is it expected to have to fill the diff before every race? If so, how do you ensure the diff gets rebuilt the same every time?

    I tried 100K, but most of that flung out of the diff after 3 runs. I moved to 500K and have had awesome performance, but it gets real messy filling, running in, then cleaning up the excess.

    I'd appreciate any advice you guys might have.
  • Boy I could say something but I won't. Fenix I like the diff and have a second one coming.
  • Quote: Hi Fenix guys,

    This isn't a quality problem, but just wanting to get advice on maintenance.

    The gear diff is working great. I did have to put a spacer between the spring and cap. The hex with the set screw would slide all the way to the end (closest to the upright) and allow the wheel hex adapter about 3mm of play. Did anyone else run into this?

    The main question is how to keep the oil from leaking when not racing. Or is it expected to have to fill the diff before every race? If so, how do you ensure the diff gets rebuilt the same every time?

    I tried 100K, but most of that flung out of the diff after 3 runs. I moved to 500K and have had awesome performance, but it gets real messy filling, running in, then cleaning up the excess.

    I'd appreciate any advice you guys might have.
    your not supposed to fill it like a car dif. Just lightly coat the gears. its not a sealed diff. depending on the surface your running on determines the thickness of the lube or grease to use. If your in the US and run on the Black CRC carpet I would recommend to start off with 100K-200k. I'm running a lot heavier than that now but our tracks traction is very high.
  • Quote: Hi Fenix guys,

    This isn't a quality problem, but just wanting to get advice on maintenance.

    The gear diff is working great. I did have to put a spacer between the spring and cap. The hex with the set screw would slide all the way to the end (closest to the upright) and allow the wheel hex adapter about 3mm of play. Did anyone else run into this?

    The main question is how to keep the oil from leaking when not racing. Or is it expected to have to fill the diff before every race? If so, how do you ensure the diff gets rebuilt the same every time?

    I tried 100K, but most of that flung out of the diff after 3 runs. I moved to 500K and have had awesome performance, but it gets real messy filling, running in, then cleaning up the excess.

    I'd appreciate any advice you guys might have.


    Gear diffs that sling silicone everywhere..... that will be easy to get out of carpet.
  • Yeah, lightly coat the gears. If you have to move up in heavier diff oil, then do so to maintain the previously lighter (but totally filled) diff.
  • I have been running spray graphite with very good results. Also tried Lucas Oil Red and Tacky which also worked well.

    chuck
  • I'm testing new tires that have a lot of rear traction on carpet, so I've already done everything I can to get the car to rotate. Loading the gear diff with 500K got the back end to slide just the right amount.

    I'm either going to half fill the diff with 500K and store the diff upright between races or lightly coat the gears with Gravity 2 Million. Seems ridiculous, but with these tires, it's only .2 slower with a 25.5 than the track hot shot with a 21.5.
  • Quote: I'm testing new tires that have a lot of rear traction on carpet, so I've already done everything I can to get the car to rotate. Loading the gear diff with 500K got the back end to slide just the right amount.

    I'm either going to half fill the diff with 500K and store the diff upright between races or lightly coat the gears with Gravity 2 Million. Seems ridiculous, but with these tires, it's only .2 slower with a 25.5 than the track hot shot with a 21.5.
    Do not half fill the diff. your only supposed to put a light coat on the gears. 2 mil is no problem I've done that this past week. Chucks suggestion of the Red grease should be a great one also.

    Just don't not fill with any amount of fluids other than a very light coating on the gears. Its will spin out do to centrifugal force and get all over your car and the track.
  • This diff is designed for grease, not fluids.
  • Quote: Do not half fill the diff. your only supposed to put a light coat on the gears. 2 mil is no problem I've done that this past week. Chucks suggestion of the Red grease should be a great one also.

    Just don't not fill with any amount of fluids other than a very light coating on the gears. Its will spin out do to centrifugal force and get all over your car and the track.
    Will do 2 million. Groovy.

    Living in Shanghai, there are no car parts stores to pick up the Lucas oil as suggested.

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