B6 S4 Motor Mounts

[gotboost]

Friend has a brand new set of OEM B6 S4 mounts that he'd give me cheap. I know they are a little shorter then the A4 mounts... but will they work in the B6 A4? Mine are in need of replacing.

[thaifoodninja]

3.0 or 1.8t?

[cschuster]

B6 mounts are the same for the 1.8/3.0

EDIT: Removed 4.2

[gotboost]

I have a 1.8t

[ECS Tuning-Audi]

B6 mounts are the same for the 1.8/3.0/4.2

Not completely the same but you can bolt up S4 mounts in an A4. S4 mounts have sensors attached to them which are supposed to show a code when they go bad.

Jason

[SJorge3442]

Not completely the same but you can bolt up S4 mounts in an A4. S4 mounts have sensors attached to them which are supposed to show a code when they go bad.

Jason

While we are talking about mounts. Arent b5,b6,b7 mounts all the same? And do they vary per engine? I would assume the 3.0 should have a stiffer mount since its heavier, but who knows.

[ECS Tuning-Audi]

While we are talking about mounts. Arent b5,b6,b7 mounts all the same? And do they vary per engine? I would assume the 3.0 should have a stiffer mount since its heavier, but who knows.

Each mount is slightly different, but as far as "bolting up" they have a universal fit.

The only mounts with the same part number are B6 1.8T and B7 2.0T mounts. Typically a different part number means there is a slight difference.

Jason

[ZipMeUpJ]

Febi b5 s4 mounts are here best bang for the buck

[gotboost]

Febi b5 s4 mounts are here best bang for the buck

I understand that, but Ill be getting these for $40.

[Jake@JHM]

B6 mounts are the same for the 1.8/3.0/4.2

False.

4.2L mounts are shorter than 1.8T/2.0T/3.0 mounts.

[cschuster]

False.

4.2L mounts are shorter than 1.8T/2.0T/3.0 mounts.

Thanks, good to know. Edited previous comment

[gotboost]

False.

4.2L mounts are shorter than 1.8T/2.0T/3.0 mounts.

Jake, I do know they are shorter. Will they work for the B6 A4 chassis?

[Jake@JHM]

Jake, I do know they are shorter. Will they work for the B6 A4 chassis?

Not recommended. it will lower your engine and drive-train and put stress on those parts

[gotboost]

Not recommended. it will lower your engine and drive-train up and put stress on those parts

Perfect, that's the answer I needed. Thanks.

[Jake@JHM]

Perfect, that's the answer I needed. Thanks.

No problem

We have A4 034 mounts in stock and ready to ship if you need them.

Jake

[ECS Tuning-Audi]

Jake, I do know they are shorter. Will they work for the B6 A4 chassis?

Your best bet is to go with something like a B5 S4 or RS4 mount if you want OEM like feel. Most other aftermarket mounts for 1.8T (poly/solid) transfer much much more NVH and give a "race car" feel. Typically not suitable for daily driving.

Jason

[Turbavanttro]

Not recommended. it will lower your engine and drive-train and put stress on those parts

Jake, I am very interested to know if you know of any B6 1.8T that used the shorter S4 mounts and had premature drivetrain wear? I'm not saying you are wrong because conceptually its logical that drivetrain wear would not decrease and if anything would increase. The reason for my inquiry, I used the Stern S4 mounts specifically due to them being shorter and because the extra 12mm kept the SEM manifold from hitting my hood. I considered the drivetrain wear issue but decided to see for myself. So far no issues and no signs of issues, but I don't have many miles on my setup yet (about 1,000).

I'm genuinely interested to know of any examples, thanks

[walky_talky20]

S4 mounts have sensors attached to them which are supposed to show a code when they go bad.

Jason

The mounts do not have "sensors". They have actuators: internal solenoids that change the fluid passages to make the mount softer, on-demand of the ECU.

If one were so-inclined to use these on a B6 1.8T, one could use an RPM-window switch to activate them, say...below 1200 rpm.

[ECS Tuning-Audi]

The mounts do not have "sensors". They have actuators: internal solenoids that change the fluid passages to make the mount softer, on-demand of the ECU.

If one were so-inclined to use these on a B6 1.8T, one could use an RPM-window switch to activate them, say...below 1200 rpm.

Never knew that.



Jason

[blownb6]

The mounts do not have "sensors". They have actuators: internal solenoids that change the fluid passages to make the mount softer, on-demand of the ECU.

If one were so-inclined to use these on a B6 1.8T, one could use an RPM-window switch to activate them, say...below 1200 rpm.

that is awesome I thought they where wear sensors as well,


I personally run b5 s4 mounts they have been great stiff but no NVH, deff better then the b6 1.8t worn out ones

[Jake@JHM]

Jake, I am very interested to know if you know of any B6 1.8T that used the shorter S4 mounts and had premature drivetrain wear? I'm not saying you are wrong because conceptually its logical that drivetrain wear would not decrease and if anything would increase. The reason for my inquiry, I used the Stern S4 mounts specifically due to them being shorter and because the extra 12mm kept the SEM manifold from hitting my hood. I considered the drivetrain wear issue but decided to see for myself. So far no issues and no signs of issues, but I don't have many miles on my setup yet (about 1,000).

I'm genuinely interested to know of any examples, thanks

I don't have any documented cases of it because we never allowed a customer to do that. However, we were one of Sterns original dealers for those mounts years ago before they had two different sizes. We had to modify the mounts to be shorter for the S4 because it was causing issues.

Having incorrect sized motor mounts can cause issue with the snub alignment, it can put unnecessary tension on hoses and harness, it can add excessive wear to the drive shaft support bearing, etc.. The whole engine and drive-train is going to be shifted either up or down depending on the application can cause fitment issues of other parts.

[old guy]

Not completely the same but you can bolt up S4 mounts in an A4. S4 mounts have sensors attached to them which are supposed to show a code when they go bad.

It isn't a sensor, it's a solenoid. The way the mounts work is that there is a fluid chamber with a plastic body in the middle of it, with small channel cut through it. this allows fluid from the top chamber, through the plastic body, to the bottom chamber. the bottom chamber is rubber lined and can deform under pressure. there is also an airway vented to atmosphere, with a rubber membrane separating the fluid from the atmosphere. The solenoid valve, controlled by the ECM can open or close the airway.

below 1100 rpm (i.e idle), the engine vibrations are not enough to force fluid from the top chamber, through the passageway to the bottom chamber. The airway is open (solenoid valve open). the rubber membrane creates a soft cushion which absorbs the high frequency vibrations.

Above 1100 rpm the solenoid valve is closed which blocks the airway and so "hardens" the mount (the fluid has nowhere to go). Thus the mount is effectively solid.

Bottom line: No advantage to using the B6 S4 mounts on an A4 since you don't have the solenoid activation available.

[ECS Tuning-Audi]

It isn't a sensor, it's a solenoid. The way the mounts work is that there is a fluid chamber with a plastic body in the middle of it, with small channel cut through it. this allows fluid from the top chamber, through the plastic body, to the bottom chamber. the bottom chamber is rubber lined and can deform under pressure. there is also an airway vented to atmosphere, with a rubber membrane separating the fluid from the atmosphere. The solenoid valve, controlled by the ECM can open or close the airway.

below 1100 rpm (i.e idle), the engine vibrations are not enough to force fluid from the top chamber, through the passageway to the bottom chamber. The airway is open (solenoid valve open). the rubber membrane creates a soft cushion which absorbs the high frequency vibrations.

Above 1100 rpm the solenoid valve is closed which blocks the airway and so "hardens" the mount (the fluid has nowhere to go). Thus the mount is effectively solid.

Bottom line: No advantage to using the B6 S4 mounts on an A4 since you don't have the solenoid activation available.

Thanks for the clarification

Jason

[walky_talky20]

Bottom line: No advantage to using the B6 S4 mounts on an A4 since you don't have the solenoid activation available.

Unless you are extra awesome, and employ a window-switch to add solenoid activation ability to your old (err..."more experienced") Audi.
http://www.ebay.com/itm/MSD-8956-rpm...c5eb7e&vxp=mtr

[Turbavanttro]

Having incorrect sized motor mounts can cause issue with the snub alignment, it can put unnecessary tension on hoses and harness, it can add excessive wear to the drive shaft support bearing, etc.. The whole engine and drive-train is going to be shifted either up or down depending on the application can cause fitment issues of other parts.

Thanks. That's all pretty straightforward, and I'm keeping an eye on things. I will document how much of an issue the B6 S4 mounts cause if used in a B6 A4 since that's what I'm currently running. So far, no issues with hose/harness tension, snub alignment was adjusted, and no excessive drivetrain vibrations so will wait and see how the drivetrain hardware holds up over time.

[Jake@JHM]

Thanks. That's all pretty straightforward, and I'm keeping an eye on things. I will document how much of an issue the B6 S4 mounts cause if used in a B6 A4 since that's what I'm currently running. So far, no issues with hose/harness tension, snub alignment was adjusted, and no excessive drivetrain vibrations so will wait and see how the drivetrain hardware holds up over time.

Yeah I wouldn't worry TOO much about it. Its not going to cause immediate failure of drive train parts but it will reduce the life of them.

[PreciseD]

Thanks. That's all pretty straightforward, and I'm keeping an eye on things. I will document how much of an issue the B6 S4 mounts cause if used in a B6 A4 since that's what I'm currently running. So far, no issues with hose/harness tension, snub alignment was adjusted, and no excessive drivetrain vibrations so will wait and see how the drivetrain hardware holds up over time.

I ran the RS4 mounts for 6 years and about 40k miles and have had no issues so I think you will be fine. Lets also note that you have lowered your vehicle which technically will wear out your CVs quicker but I bet that has not been an issue either.