Looking to replace the differential mount bushings and wonder if the aluminum ones transmit a lot of noise? Since they are solid vs the plastic I assume they would hold position better?
Differential Bushings Aluminum vs Urethane
- Thread starter CLarryL
- Start date
The rear bushing seems to transmit the most noise being attached to the diff cover. I think ac427cobra's kit has the best of both worlds. Front bushings are aluminum coupled with a Delrin rear. I have only heard good things about his stuff.
The MM aluminum bushings transmitted a lot of noise, IMHO. I eventually switched to the poly ones just to have some peace and quiet. The poly ones are definitely better than stock, but not as good as the aluminum. Why must there always be trade-offs??????? :lol1:
I have the poly and would gladly trade for Aluminum ones.It was hard to set the pinion angle with the poly.
Yeah, there was some more noise. I went and bought Raamat and made some of that noise disappear. I am glad I did the bushings because it got rid of the clunk that I was experiencing. Other says it didn't do anything for their clunk noises.
So you guys with the aluminum bushings can hear the increased noise over your exhaust?..
Also, I've read you can hear increased gear whine. Do you hear this at all times? Or only at certain RPM's or on decel or something?...
Also, I've read you can hear increased gear whine. Do you hear this at all times? Or only at certain RPM's or on decel or something?...
I put the alum kit in my last week and taking it out in the morning.
I be glade to hook you up.
I have no experience with the aluminum differential bushings, but I did pick up increased noise just going from stock rubber bushings to the polyurethane bushings. Any increase in bushing density will increase noise transmission, so it is really a matter of how much noise you are willing to put up with to gain the benefits of the stiffer bushings.
The poly bushings do melt when open tracking.
Do you have any experience with the Maximum Motorsports Polyurethane IRS bushings melting? I have heard about the Steeda's melting, but haven't found anything on the MM's melting.
i have the aluminum bushings with the delrin rear. they noise is slightly less than when i got 3.73's installed in my old 5.0. it isnt loud or anything.
as for how durable this set up is, i wouldnt recommend it. i havent had any issues or anything but as for how long the delrin holds up is a mystery apperantly.
as for how durable this set up is, i wouldnt recommend it. i havent had any issues or anything but as for how long the delrin holds up is a mystery apperantly.
why would you need to set the pinion angle with the poly bushings anyway? they shouldnt throw it off that much.
I have some poly bushings waiting for install, I would like to know this also......
GT with IRS here, Yes they transmit some slight more gears whine at some speeds. Around 40miles for me. After install,the pumpkin no longer moves in the IRS frame.
aluminum diff mounts, poly IRS mounts and delrin lower control arm bushings here. I have additional gear whine at about 40 mph also. Not a problem in the summer with windows down and stereo up. Not really too bad in my opinion. If you track the car, the aluminum mounts are a great heat sink to absorb some of the heat from the diff
I have the MM poly bushings. I did not really notice any more noise. It did make a large improvement in wheel hop and the car feeling more solid. There was also no adjustment to be made for pinion angle. You simply replace the rubber w/ the poly.
Well, because the pinion angle is not set correctly from the factory, which explains why many 2003-2004 Cobra owners complain about a vibration at 85+ mph. Urethane bushings maintain the stock geometry but eliminate rubber's damping properties, which only makes things worse (at least in my case).
I got an email from Maximum Motorsports explaining how the pinion angle should be set and confirming Ford messed up when they went to IRS in 1999.
Anyway, will be installing my aluminium kit in a few weeks and will report back as soon as the car is back on the road. If anyone wants a urethane kit, I got one I will sell for cheap. :beer:
Here's a link to a thread I started last year
http://www.svtperformance.com/forums/showthread.php?t=407597
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