[Magnum12]

Hey guys, yesterday I just replaced my right front CV axle because on my 2004 Grizzly because the previous owner rode it around with a ripped boot and the joint was going bad. For the most part the job went very smooth, disconnected the bottom shock bolt, disconnected the lower ball joint only and was able to RR and axle from there. Put it all back together and went to test ride it. One thing I noticed first thing was when I got up to speed and hit the rear brakes hard, there was a loud clunking sound coming from under the quad, right around the middle. If I used the front brakes only, no sound, if I used the rear softly, no sound but if I back down my driveway and use the rear brakes, it will make a clunking sound.

Could this be the clunking sound these atv's are known for since the rear brake is on the rear main shaft or could I have done something during the axle swap?

 

[Magnum12]

Also forgot to mention, doesn't matter if it's in 2 or 4wd, still makes the clunking sound. Also I was testing it out on asphalt and not dirt which could also be a contributing factor as well.

 

[Mud708]

Make sure rear diff isn?t moving around. Bolts loose or holes elongated.

 

[Magnum12]

I will check both front and rear when I get home! I heard that if the rear brake pads are worn it could cause that as well. Is this correct?

 

[Magnum12]

I came home and retorqued the rear diff bolts and they are tight. I did right it around and noticed when I'm going along around 5 mph and then quickly hit the gas I can hear a slight popping coming out from under the quad, between the foot pegs or slightly forward. Could this be the beginning signs of the front coupler and drive shaft going out?

 

[Magnum12]

Could there be a slim chance the new cv axle I put in is bad?

 

[reogem]

Can you describe the "clunk" a little better or record it?
Changing a front axle should have no effect on the mid or rear areas of the rig.
You will almost never hear anything from the front diff without it engages.
Noise when hard rear braking will usually cause wheel hopping that causes the suspension to rattling around.
Noise at hard braking and throttle could be rear drive shaft splines stripping, broken or loose diff or engine mounts or just the suspension storing and releasing torque.

The oneway bearing that controls the engine braking make a horrible noise when it is going out. Is you engine braking working properly? Does it freewheel at all?

 

[Magnum12]

I will try to get a recording of it and put it up on you tube later on today, have a dentist appointment for a crown later on. Your right, this whole time the bike has been in 2WD which would negate the front driveline.

The best way to describe it is it's more of a popping sound and it is very noticeable while backing down my driveway in R or N or moving forward at any speed and using the rear brake only. I also looked and there is still a lot of pad left on the rear brakes.

 

[reogem]

Now that sounds more like a cv joint or wheel bearing.

Also look inside the wheels and at the drive shaft for a stick, rock or piece of wire catching on something. I had a stick caught in a brake caliper making a scraping screech, sounded like a wheel bearing had gone out.

 

[Magnum12]

Let try and get a recording of the sound and post it up. Side question, would you happen to know the torque spec for the lower ball joint? I searched and could only find a ref of 18ft lbs which is what I torqued mine to but that seems way to light. If that's the case, I'm wondering if that's the noise I'm hearing.

 

[reogem]

Lower ball joint is 35lb

 

[Magnum12]

Ok, let me torque it down more and make sure that is not the problem. If it's not then I will try and get the recording of it.

 

[dezz]

When you checked your rear diff bolts, did you grab the two axles and try to wiggle the diff in the frame? Really yank on it hard.
In 99% of cases with a loose diff, the bolts will still be tight.

 

[Magnum12]

Here is the link to the video with the sound. The clicking/popping is created by me pressing the rear brake several times.

https://youtu.be/ATRxRwZwv7Y

 

[Magnum12]

Actually no, I just torqued down on the bolts again.

 

[guipago]

Interesting noise, can you feel anything thru the foot brake? Maybe use soft sole shoes like slippers or something like them, how about if you rest your hand on the gear lever, feel anything there? If you do feel the noise thru any of them, follow that system all the way back looking for loose nuts, bolts etc. Reogem's stones or sticks dragging is a good idea, all a matter of eliminating potential problem's to nail it down.

 

[Magnum12]

I can slightly feel it in the brake peddle but the sound seems to be coming directly below me.

 

[Magnum12]

It almost feels like it could be sloop in the drive train but it's way to loud though.

 

[guipago]

The fact that you "feel" it thru the foot is good, now you have a place to start, the brake lever goes forward towards the front drive shaft, so a stick or so could hit the shaft when the brake is pressed OR the cable that attaches from the rear brake lever to the gear shift lever so you can change the gears PRNHL is too tight & when you hit the brake it puts pressure on the gear lever & tries to change from 1 gear to another, don't know if this is possible but it's worth a look.

 

[reogem]

I'd say you need to look at the rear brake system. Maybe somethings loose or worn out or broken pad or insulators. In you video I hear a metallic scrapping at 8-9 seconds. It appears that you are going forward at that point. It sounds like a metal to metal brake scrapping.