[Bimma360]

I already made some posts about this in the Diff Bolt thread, but thought it would be a good idea to put this in its own thread to make it easier for others to find in the future.

I got in touch with Ryan through the "BMW X3M/X4M (F97/F98) Owners Group" on Facebook. He was the first one to come up with a solution to the factory diff bolt bending/snapping. He now has 3 kits: a 12mm bolt kit, a 14mm bolt kit, and a full urethane bushing kit. He isn't running a business. This is a X3M enthusiast making a product for X3M enthusiasts, and doing this on the side.

Ok onto the kit itself...

It consists of a steel sleeve, a 12.9 grade bolt, and everything has incredibly tight tolerances. As such it takes the bolt movement part out of the equation and adds a stiffer bolt to boot. The kit also came with a drill bit and some anti-seize lube.



Whether it's an actual "solution" or just a "mitigation" to the problem is anyone's guess. But I don't want any NVH increase on this car. I had the VTT diff lockdown brace on for a few days before this and the NVH, albeit somewhat minimal is not something I am willing to tolerate. And if that means I end up having to replace this bolt every few years then so be it (not saying that I will need to though). After installing the bolt kit I can confirm that it adds ZERO NVH.

The Install - what's involved and my advice.

Removing the factory rear bolt is pretty straightforward. I have a Dinan exhaust installed and all I needed to remove was the vertical brace behind the diff.



I needed to use a breaker bar extension to loosen the nut. I did all of this with the rear of the car on jack stands, the car in neutral to release the tension on the diff, and a jack under the diff itself.

Keep the following in mind: When installing this bolt kit I needed to torque the nut down to about 130 ft-lbs. Laying on my back I could only get enough leverage to get it torqued to about 115-120. If you are just replacing the factory bolt, confirm the factory torque spec and procedure to see if you can actually do this on your back under the car.. Since I am installing an aftermarket bolt, I think I should be alright at the 115/120. I marked the nut and bolt to keep an eye on movement, and worse case I get it on a lift to have it torqued to the full 130.

After the nut is off, the bolt slid right out. Hahaha Ironically enough my bolt was straight as an arrow. My X3M is a 2020 with 23k miles on it, 5 of which are under my ownership. I have never launched it under my ownership b/c of the bolt issue, but I do tend to drive it pretty hard I think. I am always in manual and sport+ on the engine. I average 11 mpg haha.



Ok so as stated the kit comes with a steel sleeve for the bolt. You have to remove the factory aluminum sleeve. This actually turned into a HUGE pain in the ass. It's not difficult, just incredibly tedious.

I decided to not use the drill bit that came with the kit, and instead went for the saw method (see YouTube video below). (1) The drill bit was actually too big for my drill haha, and (2) figured this was the best way of keeping myself from damaging the steel in the bushing. I don't know if this was the right way to go about it honestly, but I would probably do it again if I had the choice.

Here is what the sleeve looked like after some sawing and some grinding with a file.



The YouTube video makes it look easier than it actually is haha. That's b/c he was doing it with the bushing out of the car.

After hours and some trial and error here is what I came up with:

You need to let the diff drop so the ear on the diff that the bolt goes through is below the opening of the bushing bolt hole. I had to actually give the diff a bit of a pull down to get it to come down where I needed it to be.

Grab a socket that will fit in the bushing hole perfectly. Put a long bolt through it so that the bolt head rests on the socket end that would normally go on your socket wrench. Then slide the socket into the bushing hole so that it sits against the bushing sleeve and the bolt goes all the way through the bushing and out on the other side towards the exhaust. When you hold onto the bolt from the exhaust side, you are now keeping tension on the sleeve with the socket. You can now use your other hand to hit the socket with a hammer to start pushing the sleeve out towards the exhaust. It's not easy and it will take some force and some time. As the sleeve comes out, you can momentarily compress it a bit with vise grips just to close up the gap where you sawed through the sleeve in an effort to remove some of the tension. Keep doing this until it comes out. I didn't take a picture of my contraption but I can and post here if anyone can't picture what I am talking about.

And here is what the sleeve looks like out of the bushing. What a pain in the ass.



After that, lube the new sleeve with the anti-seize. You'll need to hammer it back in as the tolerance is nice and tight. Be careful not to damage the new sleeve. You'll want to hammer it in from the exhaust side towards the diff ear. The sleeve end needs to be flush with the bushing end on the diff ear side, so that when everything is bolted up the diff ear is right up against the bushing AND the new sleeve. Basically you don't want any space between the diff ear and the sleeve. I also lubed up the bolt and its threads and assembled the rest in the order the bolt kid was received as pictured in the first pic. Torque it down to 130 ft-lbs (if you can haha). And that's it!



Finally thoughts and suggestions on the install.

If you are going to do this yourself, and your car is relatively low mileage (so you may not need to replace your actual bushing), just mentally prepare for this to be a pain in the ass. That damn sleeve. If you are going to have this done at a shop regardless of mileage, please for the love of God just do the following.

Buy a new OE "Genuine BMW" bushing. Saw the sleeve out yourself. With the bushing out you can actually use the complete hand saw (just assemble it with the blade already through the bushing). AND saw through the sleeve in two spots. That will probably take you a few minutes at most. The sleeve should just about slide out. Lube up your new sleeve, and install it into the new bushing just like I described above. When you take your car to the shop, the'll just be performing the bushing change procedure using the parts you provide them. I guarantee you will pay for the same labor whether they are swapping a bushing or spending the time removing the original sleeve. Haha who knows, you may end up paying more for them to just remove the sleeve if it turns out to take them longer. This also guarantees the tech doesn't F this all up. Swapping a bushing is straightforward.

[Bimma360]

My VTT Diff Lockdown Brace Review

Here is what the kit looks like.





As some friends across the pond would say, "it's a nice piece of kit this."

The install was a bit interesting I would say. It's pretty straightforward and the directions from Vargas are good. But when I loosely mock mounted it to the subframe to see how much space there is between the diff and the the part of the brace that mounts to the diff, it was a bit more than I expected. It's hard to measure, and I didn't measure it, but it looked like about 1/4 - 1/2in. Granted when you tighten the subframe side that will compress the rubber on the brace a bit and reduce that distance a little. But even according to the directions, tightening the diff side of the brace will pull the diff snug to the brace itself. Not sure how I feel about pulling the diff down (and adding a constant force to the factory bushings) by 1/4 - 1/2in. It might be a moot point, but hey those were my observations on my particular car and almost a 1/2in didn't give me a warm and fuzzy.

In Varga's defense, they can't control the diff bushing condition of the client's cars. And perhaps that may have some effect on where the diff sits relative to the car they used when they designed their brace. And the same could be said about the car they used. Was it factory fresh or did it have some mileage? How many times was it launched? If so were all 3 diff bushings replaced with factory bushings prior to scanning the diff/area for the brace design? It's an unknown, but I figure I mention it here.

As far as what I think about the brace goes, like I mentioned in the first post the NVH is not what I am willing to accept on this particular car. VTT describes the NVH as "little to none," and I think it's more like "little to some."

Essentially, their lockdown brace amplifies engine resonance in the cabin. In other words it makes your engine sound louder. At low RPM, it's "little." Above 3K RPM its "some." Under deceleration in the 4000 - 3200 RPM range there is a pretty pronounced growl/whine. I drive the car in manual 99.9% of the time, and with the way I drive I tend to decelerate through that range pretty often.

Generally speaking, the NVH is not bad. Hearing and feeling your engine a bit more might be a good thing for some. Especially if you have a louder exhaust. Just depends on what you want out of your car. And I full well understand peoples expectations are different. For me, it turns out, only very little is acceptable on this car. The lockdown brace, to me, makes the car feel a bit more crude. I have plenty of old BMW's, I don't need this one to feel like one too.

I will say my biggest gripe with all of this is the way Vargas describes the NVH. To illustrate this a little further, with the brace installed I couldn't really hear the burbles from my Dinan exhaust. The Dinan is just a little louder than stock granted, but what that shows me is that some NVH is present basically throughout the entire rev range. Words like "little" are subjective. Someone's little is someone else's a lot. That's totally fine, I full well know this when I buy stuff like this for my cars. And that is my gamble to take. But words like "none" are objective. None means none - the absence of.

And it's not really about the money. I haven't reached out to Vargas and I am not going to. I took the gamble to try their product out and its on me. And I am not going to get all Karen on them to parse words for a few hundred bucks. I'll probably sell the brace to someone who will appreciate it and only be out a hundred or so. Just wanted to post this here to give an incredibly picky perspective to someone that may benefit from it.

[Shockalaka]

Good read, very informative. Can't wait to hear updates, pros/cons if any.

[Max Well]

Appreciate your thorough documentation and explanation, Bimma360 - should help others as they sort through the options available. I've added a link to this in the OP of the compilation thread.

[joebie3]

Excellent writeup! Now we need someone to test out the full front/rear poly kit from Ryan :-)

[TacosRule!]

Originally Posted by Bimma360

My VTT Diff Lockdown Brace Review

Here is what the kit looks like.





As some friends across the pond would say, "it's a nice piece of kit this."

The install was a bit interesting I would say. It's pretty straightforward and the directions from Vargas are good. But when I loosely mock mounted it to the subframe to see how much space there is between the diff and the the part of the brace that mounts to the diff, it was a bit more than I expected. It's hard to measure, and I didn't measure it, but it looked like about 1/4 - 1/2in. Granted when you tighten the subframe side that will compress the rubber on the brace a bit and reduce that distance a little. But even according to the directions, tightening the diff side of the brace will pull the diff snug to the brace itself. Not sure how I feel about pulling the diff down (and adding a constant force to the factory bushings) by 1/4 - 1/2in. It might be a moot point, but hey those were my observations on my particular car and almost a 1/2in didn't give me a warm and fuzzy.

In Varga's defense, they can't control the diff bushing condition of the client's cars. And perhaps that may have some effect on where the diff sits relative to the car they used when they designed their brace. And the same could be said about the car they used. Was it factory fresh or did it have some mileage? How many times was it launched? If so were all 3 diff bushings replaced with factory bushings prior to scanning the diff/area for the brace design? It's an unknown, but I figure I mention it here.

As far as what I think about the brace goes, like I mentioned in the first post the NVH is not what I am willing to accept on this particular car. VTT describes the NVH as "little to none," and I think it's more like "little to some."

Essentially, their lockdown brace amplifies engine resonance in the cabin. In other words it makes your engine sound louder. At low RPM, it's "little." Above 3K RPM its "some." Under deceleration in the 4000 - 3200 RPM range there is a pretty pronounced growl/whine. I drive the car in manual 99.9% of the time, and with the way I drive I tend to decelerate through that range pretty often.

Generally speaking, the NVH is not bad. Hearing and feeling your engine a bit more might be a good thing for some. Especially if you have a louder exhaust. Just depends on what you want out of your car. And I full well understand peoples expectations are different. For me, it turns out, only very little is acceptable on this car. The lockdown brace, to me, makes the car feel a bit more crude. I have plenty of old BMW's, I don't need this one to feel like one too.

I will say my biggest gripe with all of this is the way Vargas describes the NVH. To illustrate this a little further, with the brace installed I couldn't really hear the burbles from my Dinan exhaust. The Dinan is just a little louder than stock granted, but what that shows me is that some NVH is present basically throughout the entire rev range. Words like "little" are subjective. Someone's little is someone else's a lot. That's totally fine, I full well know this when I buy stuff like this for my cars. And that is my gamble to take. But words like "none" are objective. None means none - the absence of.

And it's not really about the money. I haven't reached out to Vargas and I am not going to. I took the gamble to try their product out and its on me. And I am not going to get all Karen on them to parse words for a few hundred bucks. I'll probably sell the brace to someone who will appreciate it and only be out a hundred or so. Just wanted to post this here to give an incredibly picky perspective to someone that may benefit from it.

Thread of the month right here. Thanks man, appreciate it!




EDIT:

1) is there any NVH added with Ryan's kit? I know from the main thread, I posted Varga's emailed reply "zero NVH".

2) Again Varga's "zero NVH" is horseshit as you reported using their brace. Can you not return it for a refund and claim bait-and-switch or false advertisement?

Thanks again for the post, we really appreciate it.

[TacosRule!]

Originally Posted by joebie3

Excellent writeup! Now we need someone to test out the full front/rear poly kit from Ryan :-)

wait, he has a front diff kit as well? Do we have any reported issues with the front diff bushing also having bolt problems?

[joebie3]

Originally Posted by TacosRule!

wait, he has a front diff kit as well? Do we have any reported issues with the front diff bushing also having bolt problems?

Yup! Poly bushings for the front diff

[Bimma360]

Originally Posted by TacosRule!

Thread of the month right here. Thanks man, appreciate it!




EDIT:

1) is there any NVH added with Ryan's kit? I know from the main thread, I posted Varga's emailed reply "zero NVH".

2) Again Varga's "zero NVH" is horseshit as you reported using their brace. Can you not return it for a refund and claim bait-and-switch or false advertisement?

Thanks again for the post, we really appreciate it.

The answers to your questions are in the 2 posts. :P

No NVH from Ryan's kit.

On the Varga's thing. I don't really care to. I talk about it more in the post you quoted. But overall, I knew I was taking a risk going with a solid brace and I don't really care to parse the words "little and none" with them from the product description. Technically "little" could mean lots of things. I am not worried about it for 300 bucks, and I don't like complaining about every little thing. I'll get some of my money back when I sell it to someone else.

[TacosRule!]

Originally Posted by Bimma360

The answers to your questions are in the 2 posts. :P

No NVH from Ryan's kit.

On the Varga's thing. I don't really care to. I talk about it more in the post you quoted. But overall, I knew I was taking a risk going with a solid brace and I don't really care to parse the words "little and none" with them from the product description. Technically "little" could mean lots of things. I am not worried about it for 300 bucks, and I don't like complaining about every little thing. I'll get some of my money back when I sell it to someone else.

Thanks for the info, I just paid for Ryan's kit. Cant wait to get this finally addressed.

[Diskz]

Originally Posted by TacosRule!

Thanks for the info, I just paid for Ryan's kit. Cant wait to get this finally addressed.

Looking forward to hearing your thoughts. Which kit did you go for?

[knali8]

Awesome detail.. thanks for the post. I am guessing your stock bolt was straight?

[Bimma360]

Originally Posted by knali8

Awesome detail.. thanks for the post. I am guessing your stock bolt was straight?

Yup!! Straight as an arrow haha.

[Burr001]

Originally Posted by TacosRule!

Thanks for the info, I just paid for Ryan's kit. Cant wait to get this finally addressed.

is there an actual link or website where he sells it? I cant seem to find the post on FB. Is FB the only way to contact him?

If not can someone forward my contact info, just PM me plz.

Thanks

[TacosRule!]

Originally Posted by Burr001

is there an actual link or website where he sells it? I cant seem to find the post on FB. Is FB the only way to contact him?
If not can someone forward my contact info, just PM me plz.
Thanks

morard26@gmail.com

Ryan replies within a couple of days, is very helpful and answered all my idiotic questions, he sent lots of pictures so I'm very happy with the decision to get his stuff. And Bimma360 already has his so yay

[Burr001]

Ty