[gtr0419]

I just replaced the front diff bushings. I pulled the differential to do it. Whoever designed the placement of the upper bushing is a #&)(*#(&_!!!, but that's another story.

Anyway, now that everything is back together, I have a whining noise coming front the front. I'm assuming it is the differential and that I haven't put the axles back in correctly. I marked the drive shaft, but it didn't dawn on me to mark the axle positions. Oops.

Anybody have any idea what's actually happened and what I need to do to fix it?

Thanks in advance.

 

[Hawkeyes]

I do not believe there is an axle position to mark? Did you use factory style bushings? What type of whining noise? Did you check your fluid level? Typically when you remove that driver side cv you likely need to replace the seal, thats where i usually lost fluid. Did you make sure you didn't dump fluid from there and make sure the seal was still flush?

 

[gtr0419]

I do not believe there is an axle position to mark? Did you use factory style bushings? What type of whining noise? Did you check your fluid level? Typically when you remove that driver side cv you likely need to replace the seal, thats where i usually lost fluid. Did you make sure you didn't dump fluid from there and make sure the seal was still flush?

I certainly did not use the factory style bushings. They're garbage. That's why we all have to replace them to begin with. I also noticed the lower control arm bushing on the driver side is not long for this world, but that's for another discussion.

I used Creative Steel Poly bushings. I highly recommend them based on my research. They are a direct fit replacement and are not the source of the noise.

I hear you about the seal. I usually replace them when I pull axles. I did not replace it, but there is no fliud leak. I considered the oil level and weight as well. I need to double check the requirements in the AM. However, it does have a complete bottle of new synthetic gear oil and all I've done was drive it around the neighborhood. Would being a litte low cause such a distinct noise?

 

[gtr0419]

I certainly did not use the factory style bushings. They're garbage which is why we all have to replace them to begin with. I also noticed the lower control arm bushing on the driver side is not long for this world, but that's for another discussion.

I used Creative Steel Poly bushings. I highly recommend them based on my research. They are a direct fit replacement and are not the source of the noise.

I hear you about the seal. I usually replace them when I pull axles. I did not replace it, but there is no fliud leak. I considered the oil level and weight as well. I need to double check the requirements in the AM. However, it does have a complete bottle of new synthetic gear oil and all I've done was drive it around the neighborhood. Would being a litte low cause such a distinct noise?

Oh, you asked about the type of whine. It is not present until you get moving and changes pitch with speed. Obvioulsy related to drive train movement.

 

[Hawkeyes]

I've used Creative Steel in mine as well, nice. Did you check your driveshaft while under there and pulling out the differential? Just wondering if that cv boot is torn on the tcase side?

Unless you lost a ton of fluid i wouldn't point to that as a cause. Im wondering if the whine is with the wheel revolutions or the driveshaft revolutions, I think they are just a little seperate. Does it stop whining briefly when you turn? Would point to a wheel hub coincidentally going bad.

So peculiar the issues we have with bushing changes lol.

 

[Jamie]

I've used Creative Steel in mine as well, nice. Did you check your driveshaft while under there and pulling out the differential? Just wondering if that cv boot is torn on the tcase side?

Unless you lost a ton of fluid i wouldn't point to that as a cause. Im wondering if the whine is with the wheel revolutions or the driveshaft revolutions, I think they are just a little seperate. Does it stop whining briefly when you turn? Would point to a wheel hub coincidentally going bad.

So peculiar the issues we have with bushing changes lol.

I'm sorry to say it but it sounds alot like differential bearings. An easy check is to put a heavier weight gear oil in for diagnostic purposes only and run it down the road. See if whining noise is leasened or possibly almost gone. If the heavier gear oil changes whine its a good possibility its bearing in differential. Since you pulled axles and put back in with new bushings which changes force applied to bearings you very easily could have a bearing issue. Just a thought from previous experience

 

[Hawkeyes]

Interesting...in general I wouldn't suspect a bushing change to cause that unless something else was at play. Glad more eyeballs are floating around.

Gtr0419 - did anything drop or possibly hit the ground on this when you pulled it out? What are your Jeep specs, mileage etc.?

 

[drm4633]

Your new CS bushings are going to transmit way more driveline noise through the chassis. Especially if you have the bottom one that bolts on. I have the cs bushings and i had to take that one off and replace with one with rubber isolators. Drove me bonkers.

 

[gtr0419]

Interesting...in general I wouldn't suspect a bushing change to cause that unless something else was at play. Glad more eyeballs are floating around.

Gtr0419 - did anything drop or possibly hit the ground on this when you pulled it out? What are your Jeep specs, mileage etc.?

Apologies for the delayed response. I had to steep away from this project for a bit.

 

[gtr0419]

Apologies for the delayed response. I had to steep away from this project for a bit.

No. Nothing fell. It's a 2008 Overland with about 90k on it.

 

[gtr0419]

Your new CS bushings are going to transmit way more deiveline noise through the chassis. Especially if you have the bottom one that bolts on. I have the cs bushings and i had to take that one off and replace with one with rubber isolators. Drove me bonkers.

Yeah, I get that, but this isn't normal driveline noise. At least not to me. It's pretty loud. Was your's a whining sound?

 

[gtr0419]

I wonder if something got damaged/bent/worn while driving it with the bad bushing and now that it's straight again it's giving me the finger for waiting too long to fix it?

 

[gtr0419]

I'm sorry to say it but it sounds alot like differential bearings. An easy check is to put a heavier weight gear oil in for diagnostic purposes only and run it down the road. See if whining noise is leasened or possibly almost gone. If the heavier gear oil changes whine its a good possibility its bearing in differential. Since you pulled axles and put back in with new bushings which changes force applied to bearings you very easily could have a bearing issue. Just a thought from previous experience

It makes sense. The bearing could have been damaged or worn and the new bushings just accelerated what was already coming.

I hate to buy oil just for a test. Hmm.

 

[drm4633]

Yeah, I get that, but this isn't normal driveline noise. At least not to me. It's pretty loud. Was your's a whining sound?

More like a low roaring noise.

 

[drm4633]

It makes sense. The bearing could have been damaged or worn and the new bushings just accelerated what was already coming.

I hate to buy oil just for a test. Hmm.

I've read you can put sawdust in for the same effect...

 

[Hawkeyes]

Did you line up your driveshaft properly? Check the cvs on that? Might have a shop put it on a lift and stethoscope it? Best idea I have (unless you feel comfortable with doing that on stands, wouldn't recommend though). A whine can be a lot of things and as I've learned it's going to be hard to pinpoint with the way sound travels through the system down there. The if it's a grumble slightly grinding howl it would put to a bearing but not a whine? If it's whining I feel something else is at play. Could definitely be a cv, how rusty is it under there? If at 90k and you just took driveshaft off for first time-recheck it.

 

[drm4633]

If you still have your old lower bushing mount, put it back on and see if it changes anything.

A whine is usually a pinion bearing...

 

[gtr0419]

Did you line up your driveshaft properly? Check the cvs on that? Might have a shop put it on a lift and stethoscope it? Best idea I have (unless you feel comfortable with doing that on stands, wouldn't recommend though). A whine can be a lot of things and as I've learned it's going to be hard to pinpoint with the way sound travels through the system down there. The if it's a grumble slightly grinding howl it would put to a bearing but not a whine? If it's whining I feel something else is at play. Could definitely be a cv, how rusty is it under there? If at 90k and you just took driveshaft off for first time-recheck it.

That's funny. Yesterday, I told my wife I'm going to put it on jack stands and have her "drive" it while I listened. She thinks I'm kidding. It's happening...I think.

Rust isn't an issue.

I've had bearings go bad in other vehicles. In my experience it's always been what I would call a roaring sound. This isn't that. The CV boots on the drive shaft look fine. Visually, the the shaft and diff look mated up correctly. Is there something specific I should look for?

 

[gtr0419]

If you still have your old lower bushing mount, put it back on and see if it changes anything.

A whine is usually a pinion bearing...

I still have it. I'll give it a shot.

 

[gtr0419]

Any one know why some people say to mark the joint postion before removing the shaft? I did, but wonder if I marked it incorrectly somehow. I didn't notice anything particular about the connection.