Differential Bushing finally failed...

[shogun32]

Yeah, once these guys sawzall the OEM bushings out, they wish they never did.

I don't know about that. I did it to both of mine. PUsh come to shove I'd simply buy a piece of suitable material and make my own on the lathe. Except the whiteline material is a bit too soft (65 Shore if memory serves) to machine whereas the BMR/Steeda solid inserts are 85-90 Shore and can be.

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[Cory S]

I don't know about that. I did it to both of mine. PUsh come to shove I'd simply buy a piece of suitable material and make my own on the lathe. Except the whiteline material is a bit too soft (65 Shore if memory serves) to machine whereas the BMR/Steeda solid inserts are 85-90 Shore and can be.

I doubt that’s “too soft”. I would be willing to bet the factory rubber is around 30-40 on a Shore scale. Still some additional strength without turning the rear complete NVH generator.

 

[2morrow]

Funny because I did the steeda black pucks and people were like "you are going to hate it".

I didn't think it was that bad at all but I have super stiff rear springs...So I upgraded to the aluminum pucks.

There is NVH but trackcar so who cares. After that and my new shifter my MT-82 sounds like it has straight cut gears.

 

[Howitzer]

I'm in the middle of a diff swap and one of my rear bushings looking worse than I thought. I installed white line pucks previously when I noticed some cracks. But...I have the diff out now so...opinions? Should I just replace the bushings entirely?

Attached pic is from between the bushing and diff.

 

[shogun32]

IMO cut them out.

 

[Howitzer]

IMO cut them out.

Yeah...I guess I may as well. Feels weird putting this back together but leaving that bushing looking like that.

Now the problem...I'd go with whiteline kdt933, but looks like these are 4-6 weeks out...I can't delay finishing this for that long. I guess bmr is an option...is there anything else? Not wanting to add a ton of NVH...car is mostly track at this point but I do drive it to the events and other trips.

 

[shogun32]

Bmr is your only other option. I would swiss cheese them a bit and counter fill with soft rubber.

 

[Howitzer]

Bmr is your only other option. I would swiss cheese them a bit and counter fill with soft rubber.

Yeah...so I also found "Energy Suspension" that makes some softer than BMR (80 durometer). But of course those were about 8-12 weeks out.

Having no time to wait several weeks, I took your advice, got some polyurethane that hardens about 45 durometer (should be about what the stock rubber is, if not a tiny bit stiffer) and filled best I could. Looks decent, seems stiff now. Kept the whiteline pucks too with the bolt shims. Hoping it'll hold. Should find out soon enough.

May end up getting the whiteline 933 as a just in case so I'll actually have it available. Really not wanting to take the diff back out though.

 

[StangTime]

Yeah...so I also found "Energy Suspension" that makes some softer than BMR (80 durometer). But of course those were about 8-12 weeks out.

Having no time to wait several weeks, I took your advice, got some polyurethane that hardens about 45 durometer (should be about what the stock rubber is, if not a tiny bit stiffer) and filled best I could. Looks decent, seems stiff now. Kept the whiteline pucks too with the bolt shims. Hoping it'll hold. Should find out soon enough.

May end up getting the whiteline 933 as a just in case so I'll actually have it available. Really not wanting to take the diff back out though.

Did you just drill and fill the factory bushings with urethane? I have the same problem but used the Steeda red pucks to reinforce and support but the noise is a bit much for me. My car has the Torsen 3.73 rear. Ford new this was a noisy bitch and tried to quiet it down with a heavy metal damper on the right rear diff mount. Without it there is quite a bit of driveline noise getting into the car so I want to fix the bushing and put the damper back on.

 

[Howitzer]

Did you just drill and fill the factory bushings with urethane? I have the same problem but used the Steeda red pucks to reinforce and support but the noise is a bit much for me. My car has the Torsen 3.73 rear. Ford new this was a noisy bitch and tried to quiet it down with a heavy metal damper on the right rear diff mount. Without it there is quite a bit of driveline noise getting into the car so I want to fix the bushing and put the damper back on.

I did.

Did you just drill and fill the factory bushings with urethane? I have the same problem but used the Steeda red pucks to reinforce and support but the noise is a bit much for me. My car has the Torsen 3.73 rear. Ford new this was a noisy bitch and tried to quiet it down with a heavy metal damper on the right rear diff mount. Without it there is quite a bit of driveline noise getting into the car so I want to fix the bushing and put the damper back on.

I did - Straight drilling didn't work very well to make a usable hole in the soft rubber though. I suggest using a small hole saw bit or just a hole punch to actually make a few usable holes. Either way, I filled with a soft polyurethane(40-45 durometer) as best I could and covered all cracking in the existing rubber. Picked up the stuff at a hardware store. I hear 3m window weld also works well (But will be a little stiffer). Mine were cracked all the way through the bushing. I filled it very thick on the diff side and very light on the rear side - so I could still use the whiteline pucks that I had to continue to mitigate further damage. Also added the full length bolt sleeves and upgraded bolts. Hoping to not have to replace the entire bushings. So far so good. I have not noticed any additional noise either.

From the diff side:

From rear of car (after everything was installed):

 

[StangTime]

I did - Straight drilling didn't work very well to make a usable hole in the soft rubber though. I suggest using a small hole saw bit or just a hole punch to actually make a few usable holes. Either way, I filled with a soft polyurethane(40-45 durometer) as best I could and covered all cracking in the existing rubber. Picked up the stuff at a hardware store. I hear 3m window weld also works well (But will be a little stiffer). Mine were cracked all the way through the bushing. I filled it very thick on the diff side and very light on the rear side - so I could still use the whiteline pucks that I had to continue to mitigate further damage. Also added the full length bolt sleeves and upgraded bolts. Hoping to not have to replace the entire bushings. So far so good. I have not noticed any additional noise either.

From the diff side:

From rear of car (after everything was installed):

Thanks! My rear bushings have what look like voids but I never determined if they went all the way through.

 

[WD Pro]

@StangTime

That looks typical of just a thin skin where the tool has worn and allowed what we could call ‘flash’ to form between the two tool halves. I reckon if you poked it with a small screwdriver it would puncture and tear away very easily.

Did both sides of your car have those voids ? Based on the rear bushings, mine only had the voids on the right side ?

WD

 

[shogun32]

I have the same problem but used the Steeda red pucks to reinforce and support but the noise is a bit much for me

only Whiteline makes a sufficiently 'soft' puck system. Steeda and BMR's cause the diff to 'sing' when you get the sympathetic resonate frequencies lined up. Before they cancelled production I installed the Whiteline diff bushing replacement kit and yes the diff would growl. But it was low dB and low frequency and not at all unpleasant unless you were expecting a factory stock quiet cabin.

 

[StangTime]

@StangTime

That looks typical of just a thin skin where the tool has worn and allowed what we could call ‘flash’ to form between the two tool halves. I reckon if you poked it with a small screwdriver it would puncture and tear away very easily.

Did both sides of your car have those voids ? Based on the rear bushings, mine only had the voids on the right side ?

WD

From the rear of the car looking forward, I can only see voids on the right hand side. The left side was solid. I couldn't see nor was I looking for voids on the other side of the bushings. My guess is they are there.
I was watching the video Steeda made of the IRS movement. That right side bushing stretches like a rubber band. So much, it's no wonder they tear.

 

[DougS550]

Hi. So what was the consensus as to the Best bushings to install in the the rear Diff and IRS subframe to reduce the movement but not increase noises or vibration like Steeda or BMR create?

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