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Discussion Starter #1
I've got a 98 big bear 350 that has a metallic squeak when I switch between forward and backward movement.

I expected it might be a u joint, but can't find a any that appear loose or locked.

There is play in one of the front wheel bearings, but I'm not sure if that would make the noise.

Anybody got any suggestions?

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Did you check the rear driveshaft u-joint under the rubber boot, located within the rear swingarm?
It's right on the back of the engine/transfer case.

Can you duplicate it on jack stands?
 

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Discussion Starter #3
I guess I wasn't aware there was a u joint there. I will put it on jack stands today and see if I can duplicate it.

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Once you got it on Jack stands, I would recheck all other u-joints. When on jack stands, there is no load on the drivetrain. Nothing can be locked up due to load. Rotate the wheels while checking over driveline parts for loose or rough operation.
 

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Discussion Starter #5
On jack stands and everything feels right, except for the play in the left front wheel bearing.

Though, how would I check the u joint under the boot?

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On jack stands and everything feels right, except for the play in the left front wheel bearing.

Though, how would I check the u joint under the boot?

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Remove the bands that hold the boot in place and pull the boot back. It's a little difficult to put back on sometimes, and space is limited to inspect.
 

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Discussion Starter #7
Ok, will do. How might I post a video? I've got one that you can hear the sound.

It does seem to be coming from the back of the machine, and does it mostly when turning.

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Discussion Starter #8
I can't feel any play in the u joint on the back of the trans. Little surface rust in there, but looks not too bad in that regard. Is that where people suggest to fill with grease?

I did however, find some play in the front driveshaft, at the differential end. There appears to be a spring loaded spline there, and it wiggles.



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Discussion Starter #9
Well, is this a grease and go or replacement situation?

Where do people fill with grease to protect the splines on the rear axle?

Is dezz the only other poster here? lol

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Calm down bud. Lots of great people here, and they'll post if the think they can help. Additionally, sometimes threads get lost in the pile and missed. Additionally again, you have an older machine, and many people do not have any experience with these units.
You might not mean it, but your last post comes across a bit negative. That will not earn you any help being like that, whether it was meant to be or not. That's how it's written.

That front driveshaft yoke and spline looks like it could use a good cleaning and greasing. It might be where your noise is coming from. Spray the area with a good penetrating oil (not WD40) and see if the noise improves. If the noise goes away or is lessened, then you found your issue. At that point, pull the front driveshaft and clean the yoke and shaft splines of rust. Apply a good quality EP Grease (marine grease is stickiest) to the splines and reassemble. The grease will get washed out 9ver time, but it still helps.

Greasing the rear driveshaft requires drilling a hole in the rear swing arm tube and installing a grease zerk. Then you grab the grease gun and get pumping. It will take several tubes to fill it. Before you do this though, it's best to remove the rear axle and clean the splines. Inspect them for wear and damage. Get them built back up by a machine shop if worn. Clean and remove as much rust and corrosion as you can, then reinstall everything. Fill with grease and go ride.
In my opinion, you should also replzce the rear axle bearings before filling the tube with grease. This is because when you do eventually get a bad beating (and it will happen), it's a gigantic mess removing the axle to replace the bearings with it full of grease.

To put it simply, I would:
Pull rear axle.
Inspect splines and get repaired (if required) if required. Once stripped, repairing is almost impossible.
Replace rear axle bearings and seals.
Put it all back together
Install grease zerk and fill with grease.
Go ride.

Greasing the rear axle is a preventative measure thing. It saves the rear axle splines from stripping due to rust. Rear axles are stupid expensive, and used ones are very hard to find right now. Saving the one you got is the best measure to keep your bike from becoming a parts machine with a stripped rear axle.
 
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