Aluminum Diff. Bushing = No Thunk

[djtyau]

I've always wanted to do this upgrade, but I was afraid of more noise, setting the pinion angle, vibration, etc. However, with all that I went ahead and purchased Bruce's bushings to do the install over the Christmas break. I also removed the differential cover and resealed it (not dropping the IRS or removing the halfshafts).

The hardest part for me was figuring out the pinion angle. Bruce tried to describe the process through many emails. I also tried MM's instructions too, but without pictures I didn't get it. So after all of that I went ahead and set it to the stock angle. I had no vibrations with that angle anyways so I figured it has to be good. One of the greatest things that happened out of all of this was that thunking was completely gone. Oh yeah, and no vibrations. :banana:

 

[Kevin the Clean 1]

I'm glad to hear that the aluminum diff bushings are not loud like some people say. Damn, I just bought the MM poly ones unfortunately. The good things is my car is not a track car so they should not get hot enough to melt. The feel pretty damn firm enough to me. :shrug: Oh well. I also have to reseal my differential cover. You say that it does not have to be broken loose from the half shafts. That is very good news.:rockon:

Please tell me how you did this. I have to reseal by differential cover, install the MM poly diff bushings & install the Billet Flow diff cover brace too... !

 

[04HarleyF250]

I searched around when I pulled my IRS apart and found a really good write up... Cant find it right now, but Ill keep looking and try and post it.

 

[NOMANIAC3]

How Can I Get A Hold Of Bruce,s Kit

 

[djtyau]

I'm glad to hear that the aluminum diff bushings are not loud like some people say. Damn, I just bought the MM poly ones unfortunately. The good things is my car is not a track car so they should not get hot enough to melt. The feel pretty damn firm enough to me. :shrug: Oh well. I also have to reseal my differential cover. You say that it does not have to be broken loose from the half shafts. That is very good news.:rockon:

Please tell me how you did this. I have to reseal by differential cover, install the MM poly diff bushings & install the Billet Flow diff cover brace too... !

You have to remove all the differential mounting bolts front and rear, catback and driveshaft. Then you might need to remove the the exhaust hangers that are direclty in front of it. This is necessary because you will pushing up the differential up and forward and it will hit the hangers. You will be surprised how much room there is once you do this. I must warn you that cover will not easily slide off because of the rear mounting bracket corner. This is the hardest part because you will be pushing up the differential up while you are trying to get the cover off. I hope you are ready for some benchpress movements. Once I got the cover off I took out my grinder and smoothed down the corner of the bracket where the cover was hitting. Then I did some test fitting and the cover slide off and on without any problems. Remember, when you put the cover back on with gasket sealant you can't have the cover hitting things or the gasket sealant will smear.

Hope this helps.

 

[djtyau]

How Can I Get A Hold Of Bruce,s Kit

http://www.svtperformance.com/forums/showthread.php?t=260665

 

[03MUSCLE]

Ill Be Putting In Bruce's Aluminum Bushings Next Week Also H&r Race Springs And Bf Irs Brace. Can't Wait Iam Going To Have Them Install By A Shop How Much Should They Charge For All Of This To Be Done?

 

[djtyau]

Ill Be Putting In Bruce's Aluminum Bushings Next Week Also H&r Race Springs And Bf Irs Brace. Can't Wait Iam Going To Have Them Install By A Shop How Much Should They Charge For All Of This To Be Done?

I really don't know. It is a lot of work. I did the subframe bushings and the differential bushings so far and that took several hours (at least for me). I had all the tools too.

 

[ac427cobra]

I've always wanted to do this upgrade, but I was afraid of more noise, setting the pinion angle, vibration, etc. However, with all that I went ahead and purchased Bruce's bushings to do the install over the Christmas break. I also removed the differential cover and resealed it (not dropping the IRS or removing the halfshafts).

The hardest part for me was figuring out the pinion angle. Bruce tried to describe the process through many emails. I also tried MM's instructions too, but without pictures I didn't get it. So after all of that I went ahead and set it to the stock angle. I had no vibrations with that angle anyways so I figured it has to be good. One of the greatest things that happened out of all of this was that thunking was completely gone. Oh yeah, and no vibrations. :banana:

Darryl:

Glad to hear the "Thunk" is gone but I always thought is was "The Cobra Clunk"? ;-)oke:

So I guess people don't have to live with the dreaded clunk if they don't want to. :shrug:

It's amazing the comments I get from people like you telling me how totally destroyed BOTH the front and rear rubber mounts once they removed them from the car. :-D

Glad to hear the good news. epper:

:thumbsup::coolman::beer:

 

[djtyau]

Darryl:

Glad to hear the "Thunk" is gone but I always thought is was "The Cobra Clunk"? ;-)oke:

So I guess people don't have to live with the dreaded clunk if they don't want to. :shrug:

It's amazing the comments I get from people like you telling me how totally destroyed BOTH the front and rear rubber mounts once they removed them from the car. :-D

Glad to hear the good news. epper:

:thumbsup::coolman::beer:

Ha Ha! Yeah, I tell it how I hear it. It sounded to me like a thunk instead of a clunk.;-)

 

[sixpackstang]

This sounds like I need to get aluminum differential bushings right away. I've got the clunk-thunk going on, and I was pretty clueless for awhile till I started researching here.

I thought with my mods that I had already (MM poly diff bushings, MM poly IRS subframe bushings, BF diff brace) that I would never get the clunk. But thanks to one mis-shift at the strip, there it was. I sort of ruled out the diff bushings but I think they need to be looked at. I also need to finally install those BF IRS subframe mount braces and get them welded up too.

 

[Kevin the Clean 1]

This sounds like I need to get aluminum differential bushings right away. I've got the clunk-thunk going on, and I was pretty clueless for awhile till I started researching here.

I thought with my mods that I had already (MM poly diff bushings, MM poly IRS subframe bushings, BF diff brace) that I would never get the clunk. But thanks to one mis-shift at the strip, there it was. I sort of ruled out the diff bushings but I think they need to be looked at. I also need to finally install those BF IRS subframe mount braces and get them welded up too.

It's not the differential bushings (trust me). It's the back lash in the rear diff. Those angle cut gears are the culprit...

 

[sixpackstang]

It's not the differential bushings (trust me). It's the back lash in the rear diff. Those angle cut gears are the culprit...

Then why did it completely solve this guys problem??? Besides, the first thing I did after it started was take it to a performance shop and have them check out the differential. They said it was fine.

If I pull the ebrake on my car so the wheels don't turn, and its sitting on level ground, I can actually push it front-to-back, back-to-front and the car moves a little bit. It's got to be some major play in the IRS somewhere. Probably a combination of the diff bushings and subframe bushings.

 

[djtyau]

Yeah, the differential bushings were causing the loud clunk at low speeds. I know about the drivetrain lash and I am not referring to that noise.

 

[Jroc]

Bruces bushing kit is an awesome mod. It does wonders for the car.

 

[Jroc]

Sorry. Double post.

 

[sixpackstang]

Yeah, the differential bushings were causing the loud clunk at low speeds. I know about the drivetrain lash and I am not referring to that noise.

Exactly, my car has always had some slop in the drivetrain that made small noises when shifting/slowing down. But this is a much louder clunk than it ever made before, and you can actually feel it in the car like the IRS is moving around.

 

[Kevin the Clean 1]

Then why did it completely solve this guys problem??? Besides, the first thing I did after it started was take it to a performance shop and have them check out the differential. They said it was fine.

If I pull the ebrake on my car so the wheels don't turn, and its sitting on level ground, I can actually push it front-to-back, back-to-front and the car moves a little bit. It's got to be some major play in the IRS somewhere. Probably a combination of the diff bushings and subframe bushings.

I'm just telling you what a top notch pro here in Northern California told me. This guy does not mess around. He works on rare high priced exotics & expensive sport cars. He use to own a well known Mustang shop for 9-10 years so I have a good feeling he knows what he is talking about. I have done the IRS subframe bushing upgrade, the diff bushing upgrade, & the 14mm bolt upgrade & the clunk is still there.

 

[remsvt]

I'm just telling you what a top notch pro here in Norther California told me. This guy does not mess around. He works on rare high priced exotics & expensive sport cars. He use to own a well known Mustang shop for 9-10 years so I have a good feeling he knows what he is talking about. I have done the IRS subframe bushing upgrade, the diff bushing upgrade, & the 14mm bolt upgrade & the clunk is still there.

Yep, I've done all that and then some and still have the clunk. Put the car in gear and see if you can rotate the driveshaft. If you can, theres your clunk = driveline back lash.

 

[snkepit]

I did the aluminum bushing and it is a little loud but no thunk. And less vibe