Leaf spring poly bushings -source of noise?

[440beep]

Over the winter I installed new MP XHD springs and poly bushings on my Bee. Now, when I turn corners, there’s a metal grating or slapping noise coming from the rear.

I know others have said the poly bushings are firm and maybe noisy, BUT FOR THOSE THAT HAVE OR TRIED poly bushings, what kind, if any, odd noises did you have?

All the bolts are tight and the poly bushings are the only difference from prior leaf springs. Do new leaf springs need time to break in? Or is it most likely the polys?

 

[PRND21]

I’ve got poly bushings in Super Stock springs on my 65 Belvedere and have no noise. Did you use the silicone grease that comes with the bushings?

 

[440beep]

Yes, I used the poly lube that came with the bushings. But I took the springs off a couple of times and ended up using normal grease also. Wonder if I should disassemble again, clean, and recoat with poly lube only?

And now that I think of it, after driving the car after the install, I did notice heaps of the Mobil grease got squeezed out so wonder if the shackles are lacking poly grease......

I’ve got poly bushings in Super Stock springs on my 65 Belvedere and have no noise. Did you use the silicone grease that comes with the bushings?

 

[beanhead]

For what it's worth, and not trying to be all doom and gloom here, but..anytime I've encountered a "grating or slapping" noise from the rear when turning, it was ALWAYS the rear end...clutches, spiders, or maybe bearings....could be a coincidence that it started after your bushing swap. I've had polys and springs squeak but that's it for weird noises, unless something's really in a bad bind. Sounds like the same symptoms I encountered with two different clutch style sure-grips (power-lok ) breaking spider teeth. Bearings failing like to make a scraping noise, like metal on metal..

 

[440beep]

I had a brief thought last night as I was turning a corner and it started chattering if it might be the diff. Hoping it's only a fluid issue and nothing major. The axle is a Dana 60.

It only started after the new leafs were installed. If the pinion angle was off (if I remember, think it was a 2" lift over the old leafs), would this cause the cornering chatter?

For what it's worth, and not trying to be all doom and gloom here, but..anytime I've encountered a "grating or slapping" noise from the rear when turning, it was ALWAYS the rear end...clutches, spiders, or maybe bearings....could be a coincidence that it started after your bushing swap. I've had polys and springs squeak but that's it for weird noises, unless something's really in a bad bind. Sounds like the same symptoms I encountered with two different clutch style sure-grips (power-lok ) breaking spider teeth. Bearings failing like to make a scraping noise, like metal on metal..

 

[beanhead]

I had a brief thought last night as I was turning a corner and it started chattering if it might be the diff. Hoping it's only a fluid issue and nothing major. The axle is a Dana 60.

It only started after the new leafs were installed. If the pinion angle was off (if I remember, think it was a 2" lift over the old leafs), would this cause the cornering chatter?

You should recheck your pinion angle, but I'm not sure if that would necessarily cause the problem you're having?... I think that with the pinion angle being off, you would notice noise or vibration driving straight as well. Your Dana should have the clutch diff in it unless you've added a locker or something aftermarket, so maybe for starters get an extra bottle of limited slip additive (the Ford stuff) throw it in there and see if it helps at all. Absolutely though, check all the easy stuff you can check first, opening up the diff would be a last resort but with the Dana at least you can just pop the cover off... not near the drama of opening up an 8-3/4.

 

[440beep]

Yea, there's no drive line issues when going straight. And it's still the stock Dana 60. I have the Mopar diff fluid, but will crawl under there and check the fluid level. Probably been 2,3 years since I checked the fluid level.

 

[PRND21]

I had a brief thought last night as I was turning a corner and it started chattering if it might be the diff. Hoping it's only a fluid issue and nothing major. The axle is a Dana 60.

It only started after the new leafs were installed. If the pinion angle was off (if I remember, think it was a 2" lift over the old leafs), would this cause the cornering chatter?

Could it be that you’re feeling the chattering more with the poly bushings?

 

[440beep]

Not really feeling it, it’s more the loud obnoxious noise.

Could it be that you’re feeling the chattering more with the poly bushings?

 

[440beep]

Following the FSM trouble shooting test, I had the rear tires off the ground, car in park, and could not turn either wheel. Therefore rear diff should be fine. Checked the fluid level and it was low. Added some Lucas 75w90 gear oil mixed with the mopar LSD additive.

Hopefully rain stops tomorrow so I can test her out. Hoping it was a fluid level issue.

 

[440beep]

Issue discovered. Drive shaft hitting the safety loop. A non catastrophic fix.