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Grizzly 700 - Diff lock trouble

5153 Views 10 Replies 7 Participants Last post by  oleblue22
1st Issue: Servo??
Grizzly physically engages in Diff lock but will not disengagewhen button pressed to change to 4wd or 2wd. No movement of servo motor isheard at this point. As per step by step instructions on the website 501parts.com,I checked switch, relays, and servo motor and all is good. Once servo motor isremoved from front differential, pinion gear rotates as requested when buttonsare pressed. (completed numerous times). Note:I noticed that the slide rack that the pinion gear meshes with to move from 2wdto 4wd to diff lock sticks intermittently and often will not go all the way tothe far right position in the differential.
2nd Issue/Concern: Differential???
Physically removed front differential from grizzly andplaced on the bench. I manually activated the slide gear, by hand, to move itto the 2wd drive position, (Left side), 4wd position, (middle) and 4wd difflock, all the way to the right while slowly changing rotational position of thedriveshaft to allow for gear tooth alignment. Over many times moving the slide rack back andforth, I noticed that it would stop solid and not advance all the way to thefar right, (approx.. 0.150” away from end) and less than often it would advance to its far rightposition, (very intermittent). In this position, the internal female spline on thecollar gear was engaged with its mating male spline for 4wd but the outsidemale spline on the collar would not mate with the female spline to allow it tomove all the way to the right.
1) Is thisnormal operation for the diff? Is there a mechanical issue with the diff?
2) Once installed on the bike, Why will the servo motor not move out of diff lock as outlined in 1st issue above? Not enough power?
Please see pics below, rotate clockwise to view. I have a video but don't know how to upload it.
Any advice please, I am stumped.


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Welcome from Colorado.
That's a lot to absorb, but;
You can upload your video to Youtube, just start an account and follow the instructions then link the video to your post on G.C.
On the bench you stated will slide by hand? but not engage every time. Are the gears smooth?
Was the grease in the diff clean?
These guys have great troubleshooting videos for the Grizz 4wd system: http://www.501parts.com/

EDIT: I just got to actually read your post, I’m an idiot... you already mentioned 501parts.

All gears look good. No damage noticed. Differential fluid was changed in the spring and looked good. Mostly wondering if is normal for the diff to only go all the way to the right every so often when it is pushed by hand? Most times it stops about 1/8" before it's fully to the right.
If there is a blind hole
Check to make sure it is clean and no abnormal wear in shafts or bushings,,,,
If there is a blind hole
Check to make sure it is clean and no abnormal wear in shafts or bushings,,,,
Thanks but there doesn't appear to be any abnormal wear on the gears or shafts or bushings.

I talked to Steve at 501 parts yesterday and he believes that the differential is working properly and it is normal for it to not go all the way to the right on the majority of occasions. It will only align itself every so often.

Looks like my servo motor may not be providing enough power even though it passed all the checks.

I'm going to order another servo assembly and hopefully that fixes my problem.

Thanks for you advice.

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I have a 2016 Grizzly 700 and had this same problem. I took it to the dealer and they couldn’t find any obvious reason. Then they looked deeper and found a “service bulletin” and ended up fixing it for free.

They had to replace the digital display for whatever reason, but it fixed the problem. No issues engaging or disengaging now.
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Craig, never heard back from you on this so I'm assuming the new servo fixed your issues. Let us know what come of it if you don't mind, it may help out another member. Thanks!
Received rebuilt servo assembly from 501 parts and installed. Initially, it would not go into diff lock but after discussing issue with Steve from 501 parts, I unbolted the servo and repositioned the pinion gear multiple times to the slide rack in the differential and finally got it to work.
So far so good after test drive. Thanks to all for comments and especially to Steve from 501 parts.com.
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Thanks for the update, glad to hear you got it going!
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