DIY: TGK Motorsport Subframe Inserts Tutorial

[Akakios]

Just finished installing the TGK Motorsport Subframe Inserts on my Audi S7, and wanted to share the process along with some tips. These inserts are a great upgrade if you’re looking to tighten up the rear end and improve chassis stiffness, especially if you track the car or just want a more planted feel on spirited drives.

Tools I used for the install:

18mm & 19mm sockets
T25 & 10mm sockets
Extensions
1/2” ratchet or breaker bar
1/2” torque wrench
Installation Notes: The stretch bolts need to be replaced during the install, so make sure you have new ones on hand. The torque spec is 115 nm + a 90-degree turn on the bolts for a proper fit.

ONLY DO ONE INSERT AT A TIME

The process is pretty straightforward, but having the right tools and knowing the specs beforehand made it a lot easier for me. The improvement in chassis feel is immediately noticeable!

Thank you all!

[Kraus247]

That actually looked like a pain in the ass to remove. I thought this would be zip zip. I might have to free up some time to install these.

[Audisthesia]

Bro showing his age signing the OG commercial slogan....

[viper04]

Thanks for posting. May get some.

[blubaru]

I just did these and used new bolts - I had to use a jack to lift the front section of the subframe to close the gap between the body so that the threads would catch. I didn’t realize the subframe sags a bit when you remove the bolts in the front - the rear was fine and didn’t need to be lifted.

[Audisthesia]

Thanks for posting. May get some.

If you saw the video showing how much the rear subframe moves under load on stock inserts, you'd be buying them right now.

[viper04]

If you saw the video showing how much the rear subframe moves under load on stock inserts, you'd be buying them right now.

LOL! I seen it and install them this pass weekend. I did end up with the O34 Motorsports one tho.

[viper04]

I just did these and used new bolts - I had to use a jack to lift the front section of the subframe to close the gap between the body so that the threads would catch. I didn’t realize the subframe sags a bit when you remove the bolts in the front - the rear was fine and didn’t need to be lifted.

I had the same experience. Not sure why the front would sag and not the rears.

[Akakios]

Did you guys do one corner at a time or try to do the fronts both at the same time and then rears?

I highly recommend these for sure, the plastic insert that is in there from the factory they deem a locator to just make sure the bushing is centered when tightened. Once you put the insert in, there is no more slop on the area at all

Bro showing his age signing the OG commercial slogan....

For all to see, this is why you NEED these:

https://www.youtube.com/shorts/HH83yNo_cG8

https://tgkmotorsport.com/products/t...let-insert-kit

[Kraus247]

Did you do one at a time? I find it odd that it would sag with only one bolt out, but I could be wrong

[blubaru]

Did you do one at a time? I find it odd that it would sag with only one bolt out, but I could be wrong

I did one at a time so not sure either. Maybe it’s better to start with the fronts? I have also noticed a clunk type noise in the back that I’m trying to troubleshoot, it happens when I’m off the gas coasting and get back on the gas. I’ve gone back and made sure all the diff and subframe bolts are tight so who knows. Next step is to rig up a GoPro underneath and see if I can observe what’s causing the noise lol

[Akakios]

Did you do one at a time? I find it odd that it would sag with only one bolt out, but I could be wrong

That is correct, one at a time and I stress this in the video. There is that much play in the stock rubber bushing before the inserts are in (watch the TGK video above).

Blubaru Did you torque it to the specified value and then apply the correct angle? If not, you’ll almost certainly experience clunking. The angle stretch on these bolts is absolutely critical—that’s why they’re designed to be so robust.

Another good comparison video (on 034's set):

https://www.youtube.com/watch?v=W_45QrY4Erk

[blubaru]

That is correct, one at a time and I stress this in the video. There is that much play in the stock rubber bushing before the inserts are in (watch the TGK video above).

Blubaru Did you torque it to the specified value and then apply the correct angle? If not, you’ll almost certainly experience clunking. The angle stretch on these bolts is absolutely critical—that’s why they’re designed to be so robust.

Another good comparison video (on 034's set):

https://www.youtube.com/watch?v=W_45QrY4Erk

I used new bolts and did the torque plus angle, but then had to loosen them a little to do the Diff top insert as there wasn’t enough room once these were installed. So I torqued them to 120 Nm after. I may just get new bolts to rule that out but I’ve doublechecked them and they are still clicking at 120 Nm on the torque wrench. I also did the JXB carrier bearing too so everything should be nice and tight.

[blubaru]

Update - I bought the Powerflex yellow transmission insert and almost all of the clunk is fixed! I noticed the rubber on the transmission mount was very collapsed, and even with the billet insert installed I was able to slightly move the transmission up and down, due to the metal rectangle mounting surface sitting higher than the surrounding rubber - there is a small gap between the insert and the rubber. I noticed that the Powerflex mount goes fully around the metal mount block and has material that sits between the stock insert plate thing and the rubber. Take a look at the pic on their install and it will make more sense. I’m planning on getting a new trans mount but I can’t believe the difference this insert made, so I’m leaving this here in case it helps someone else diagnose their clunk issue.

https://www.powerflexusa.com/fitting...6sUr80ldrxowUv

[Akakios]

Update - I bought the Powerflex yellow transmission insert and almost all of the clunk is fixed! I noticed the rubber on the transmission mount was very collapsed, and even with the billet insert installed I was able to slightly move the transmission up and down, due to the metal rectangle mounting surface sitting higher than the surrounding rubber - there is a small gap between the insert and the rubber. I noticed that the Powerflex mount goes fully around the metal mount block and has material that sits between the stock insert plate thing and the rubber. Take a look at the pic on their install and it will make more sense. I’m planning on getting a new trans mount but I can’t believe the difference this insert made, so I’m leaving this here in case it helps someone else diagnose their clunk issue.

https://www.powerflexusa.com/fitting...6sUr80ldrxowUv

I have this insert too versus a straight billet part.

My transmission mount is done for, and I have a new one on the bench so a video will be coming for that at some point.

I suspect a lot of people's "vibrations" that they experience suspecting it's the center support bearing is just the transmission mount blown since it has a fluid filled mount as well.

[NorthernGTI]

I have this insert too versus a straight billet part.

My transmission mount is done for, and I have a new one on the bench so a video will be coming for that at some point.

I suspect a lot of people's "vibrations" that they experience suspecting it's the center support bearing is just the transmission mount blown since it has a fluid filled mount as well.

Do you think there is a increase in NVH levels with the powerflex trans insert?

[Akakios]

Do you think there is a increase in NVH levels with the powerflex trans insert?

You can hear the DSG working it's magic a little more at low low speed (I'm talking below 5 mph), but no increased VH on that side at all. I had to shave my power flex insert down to fit into my mount as it had excess casting material on it that a Dremel easily took care of.

We basically have a two-piece transmission mount, and the lower part is fluid filled and has rubber mounts so that's what we are bracing. We are trying to unify that two piece into one essentially.

[blubaru]

For me, the billet insert caused a ton of noise, engagement was very rough unless I was driving very carefully. I thought it was coming from the driveshaft or the differential. The car drives 100% better now, even the subtle jerkiness when coming to a stop has gotten better. Powerflex has yellow or black series, the yellow being softer. I would imagine the black series would have a lot more NVH as it is closer to a “solid” mount whereas the yellow is pretty flexible. I have full billet inserts on diff and subframe and also JXB DS carrier and I’m really happy with the feel now - just need to get a new trans mount for it to be really 100%.

[Akakios]

For me, the billet insert caused a ton of noise, engagement was very rough unless I was driving very carefully. I thought it was coming from the driveshaft or the differential. The car drives 100% better now, even the subtle jerkiness when coming to a stop has gotten better. Powerflex has yellow or black series, the yellow being softer. I would imagine the black series would have a lot more NVH as it is closer to a “solid” mount whereas the yellow is pretty flexible. I have full billet inserts on diff and subframe and also JXB DS carrier and I’m really happy with the feel now - just need to get a new trans mount for it to be really 100%.

I'll agree with this. Anywhere I could use urethane I did so as it's my daily. You still have the rubber to depend on with billet but that's very little play at that point. My rear upper diff mount inserts are the ECS inserts because they were urethane (and power flex was sold out of that spot at the time).

[NorthernGTI]

For me, the billet insert caused a ton of noise, engagement was very rough unless I was driving very carefully. I thought it was coming from the driveshaft or the differential. The car drives 100% better now, even the subtle jerkiness when coming to a stop has gotten better. Powerflex has yellow or black series, the yellow being softer. I would imagine the black series would have a lot more NVH as it is closer to a “solid” mount whereas the yellow is pretty flexible. I have full billet inserts on diff and subframe and also JXB DS carrier and I’m really happy with the feel now - just need to get a new trans mount for it to be really 100%.

I was looking at their red one for my tdi. I didnt find too much info out there as not many people are modding their tdi's in North America.

Just trying to figure out a game plan as far as maintenance/upgrades. Im planning on replacing my trans mount soon so I mind as well do this at the same time.