Are Differential Mount Bushings Worth the trouble?

[mhog]

I've done a few suspension mods to my camaro with great results. The latest was the Pfadt sways and springs, and what a difference. Its a new car. Are the differential mounts bushings worth doing?

[The Stig]

Yes, under WOT the differential undergoes a lot of displacement. This displacement is HP robbing.

[DallasMike]

YES! There's a ton of movement in the rear diff. This is one of the three must do bushing changes.

[mhog]

Thanks! Well its back under my camaro. This car has me on my back like the a $2 whore.

[hypurone]

Originally Posted by mhog

Thanks! Well its back under my camaro. This car has me on my back like the a $2 whore.

[Apex Motorsports]

Originally Posted by stieger

Yes, under WOT the differential undergoes a lot of displacement. This displacement is HP robbing.

+1 Here is a good video.

[PfadtRacing]

Originally Posted by mhog

I've done a few suspension mods to my camaro with great results. The latest was the Pfadt sways and springs, and what a difference. Its a new car. Are the differential mounts bushings worth doing?

hey mhog, sorry to be late to the party, but as others mentioned, yes, this is a great mod to do. Take a look at the short video we put together on differential testing.



In addition, what a lot of people will find convenient is doing the Solid subframe bushings together with the differential bushings to make a rear end that is NOT to be messed with in terms of performance! The work for the Solid subframe bushings overlaps work for the differential so you save on labor, but there are alternative methods to installing the differential bushings by themselves.

If you are looking to end rear end movement to make the car have a much better planted feel and stable handling performance, then I would recommend both of the bushing sets. If you are looking to curtail and prevailing drivetrain slop, then certainly the differential bushings by themselves are the way to go!



Give us a ring with any questions!

[JusticePete]

Originally Posted by mhog

I've done a few suspension mods to my camaro with great results. The latest was the Pfadt sways and springs, and what a difference. Its a new car. Are the differential mounts bushings worth doing?

I make my living manufacturing and selling suspension parts. Our full Justice Package is awesome, but is isn't something that everyone needs or wants. Before we start throwing parts at your 5th Gen it would be useful to know a bit more about your car and your driving style.

1. please list your current suspension mods
2. What is your current RWHP?
3. What is your planned RWHP?
4. What is your current wheel and tire package? Do you plan to change it?
5. Would you classify your car as a daily driver with an attitude or a part time race car (drag, autocross or road course)?

If we know what your expectations for the car are along with your current and future mods we can help you plan out your suspension modifications to suit your particular use. That will get you the biggest bang for your mod bucks.

[PfadtRacing]

Originally Posted by Apex Chase

+1 Here is a good video.

CHASE!!! Why do you have to be better than me?

|Blair

[SSOOCH]

YES! Do it. If they made these bushing for My hips Mrs. SSOOCH would be much happier!!

[JusticePete]

Pedders and others make differential bushes for the Camaro. They all reduce the movement of the differential under load. The question isn't do differential bushes reduce movement, we all know they do. The questions are:

Is reducing differential movement important to a daily driver? The answer would be no. Are they important to drivers that are looking for more from their cars? The answer would be maybe. In our 5th Gen Book on Suspension we list the foundational elements that are mission critical to performance in a 5th Gen.

1. Sub-frame inserts or full bush replacement
2. Radius bush inserts or full bush replacement
3. Ride Height and Dampening
4. Sway Bars

You will notice that differential bushes do not make the top four in the 5th Gen suspension mod list. There are different levels of builds a 5th gen owner will find desirable. They will be determined by the owner based on driving preferences and mod budgets. One thing we do know is that an integrated solution will yield the best result at the lowest possible cost.

The other factor is the owners tolerance for noise in the cabin. Differential bushes are the most critical bush for cabin noise levels. A solid urethane differential bush will absolutely positively transmit more cabin noise. It would be pointless to argue the point. The more dense the bush material the more noise it will transmit. That is why the OE bushes are relatively soft rubber with significant Noise Vibration and Harshness (NVH) voids. They keep the cabin isolated from differential noise.

There is a performance gain to be found with higher durometer differential bushes. That is why Pedders offers two types of differential bushes. Both are urethane, but the EP1167 has holes to control cabin noise levels. The urethane is higher durometer than the OE rubber and the holes are smaller. The bush offers greater control at a minimal increase in cabin noise level. The EP1167HD is a solid bush and in a higher durometer than the EP1167. It offers great control, but at a price. It will increase the amount of differential noise transmitted to the cabin.

I am all for selling parts, but we do need to keep the Camaro5 members informed on both the gains and the costs of upgrades. That brings us back to the OPs original question -- Are the differential mounts bushings worth doing? For some drivers yes and for others no. It is driver and build dependent.

[gahammerle]

Originally Posted by mhog

Thanks! Well its back under my camaro.

I see you are driving a V6. Unless you have added forced induction, the power that the V6 has doesn't really require differential bushings, does it?

[PfadtRacing]

Originally Posted by gahammerle

I see you are driving a V6. Unless you have added forced induction, the power that the V6 has doesn't really require differential bushings, does it?

You have the right idea that as the power output increases, you should consider the differential bushings as well as other drivetrain isolators like engine mounts. But, as an integral part of the rear end, having a V6 or V8 does not affect the fact that these bushings can contribute to unwanted rear end instability, but also wheel hop.

So it is just a matter of what your goal is as I mentioned before, if it is to isolate potential rear end movement and keep the diff planted in the subframe then it this is the mod for you! If your goal is rear end stability and improved handling than the solid rear subframe bushings and rear differential bushings is the right package to make that happen for a V6 car or a V8 car.

[mhog]

Originally Posted by JusticePete

Pedders and others make differential bushes for the Camaro. They all reduce the movement of the differential under load. The question isn't do differential bushes reduce movement, we all know they do. The questions are:

Is reducing differential movement important to a daily driver? The answer would be no. Are they important to drivers that are looking for more from their cars? The answer would be maybe. In our 5th Gen Book on Suspension we list the foundational elements that are mission critical to performance in a 5th Gen.

1. Sub-frame inserts or full bush replacement
2. Radius bush inserts or full bush replacement
3. Ride Height and Dampening
4. Sway Bars

You will notice that differential bushes do not make the top four in the 5th Gen suspension mod list. There are different levels of builds a 5th gen owner will find desirable. They will be determined by the owner based on driving preferences and mod budgets. One thing we do know is that an integrated solution will yield the best result at the lowest possible cost.

The other factor is the owners tolerance for noise in the cabin. Differential bushes are the most critical bush for cabin noise levels. A solid urethane differential bush will absolutely positively transmit more cabin noise. It would be pointless to argue the point. The more dense the bush material the more noise it will transmit. That is why the OE bushes are relatively soft rubber with significant Noise Vibration and Harshness (NVH) voids. They keep the cabin isolated from differential noise.

There is a performance gain to be found with higher durometer differential bushes. That is why Pedders offers two types of differential bushes. Both are urethane, but the EP1167 has holes to control cabin noise levels. The urethane is higher durometer than the OE rubber and the holes are smaller. The bush offers greater control at a minimal increase in cabin noise level. The EP1167HD is a solid bush and in a higher durometer than the EP1167. It offers great control, but at a price. It will increase the amount of differential noise transmitted to the cabin.

I am all for selling parts, but we do need to keep the Camaro5 members informed on both the gains and the costs of upgrades. That brings us back to the OPs original question -- Are the differential mounts bushings worth doing? For some drivers yes and for others no. It is driver and build dependent.

I have the 1 thru 4 mods you sugested. All are great mods.