A friend of mine dropped off his '07 400 x2 for me to try to diagnose
the kak kak kak he gets in reverse. I do all my own work on my
500's so I agreed to check it out.
The machine has over 2500 miles on it (hard miles).
I jacked up the rear of the machine and put her in reverse and yes,
a god-awful clacking.
The clacking isn't present in forward gears.
When I turn it off and try to turn the rear tires by hand, whichever
tire I turn (rear tires) the other tire will turn the oposite direction.
And the clacking is still there. I yanked a bit on the rear cv/axle and
it's not the tightest in the world but I think this isn't the problem.
The tires not being in sinc is not a good sign. This opposite rotation
happens in ALL gears and some motion present even in Park.
Is my diagnosis of a rear diff gone bad accurate?
What else COULD it be?
Now the big question...how big a job would it be to fix it?
Special tools needed?

Oh, where are my manners? 1st post and all
I'm living in the Mts of NM and have 5 sportsmans (500's).
I run a small rental and tour business and do a lot of pleasure riding.

-Rustyhammer

 

Plunging joint and cv joint WILL eventually clack in reverse after hard use. Big ball bearings in plunging joint wear in the channels and when changing direction will make noise,same thing for outboard cv. Hate to say NORMAL,but most do. If starts making noise in FORWARD and REVERSE, replacement probably needed if you dont want to continue hearing noise. Have done partial replacements (plunging or cv joint),but puts more stress on remaining joint and it too will eventually need replacement! When they get that bad cheaper to replace as assy than trying to repair only partial. Usually have this problem after machines about 5 years old. 07 model you say? MUST have been really ridden hard! If tranny ok and shifts good, driveshafts sound like what you are describing.

 

Thanks for the reply.
So what do you think the deal is with the wheels turning in opposite directions
when the motor is off?
This is what made me think rear diff.

-R

 

this is normal for the wheels to do that

 

i dont think the wheels turning is the oppisite direction is correct for sure as it should be locked in all the time. cv joints do have a popping or however you describe it sound when there bad and do sometimes only make the sound under certain pressure but it doesnt sound like its a cv joint to me. imo.

 

if its an x2 it has turf mode turn switch on and make sure its NOT in turf mode and try it wheels should be locked together at this point. if noise is gone or it still turns opposite ways id say ya got somethin messed up in the rear end

 

When I was turning the wheels (while jacked up) the machine was in 2 wheel drive mode.
I'm sure the rear axles/cv's will probably need replacement but the issue I'm trying to
diagnose is the noisy rear end in reverse.
So far things seem to be pointing towards the rear end. It's pretty sloppy back there.
I've never rebuilt one. I'd have to take a lot of crap off just to GET to it!

Anyone else have any input on this?

-Rustyhammer

 

My 400 clacked in reverse because of worn wheel bearings. I replaced them and the sound went away. You should be able to check the play by jacking up the rear and try to move the tire.

 

<div class="FTQUOTE"><begin quote>Originally posted by: colt2245p

if its an x2 it has turf mode turn switch on and make sure its NOT in turf mode and try it wheels should be locked together at this point. if noise is gone or it still turns opposite ways id say ya got somethin messed up in the rear end</end quote></div>

Bingo!

 

Thanks to all who replied.
My first thread on this forum and all of you have been very helpful.
I appreciate it!
I'm not willing to tear into this project but will refer him to a pro (non dealer).
I'll be dropping by from time to time.
Peace to all.

-R