The Infamous Rusted Batwing Job (Front Crossmember Brace)

[anewstartinchrist]

On my 2012 m37x I wanted to go ahead and replace the batwing since it is rusty. Part of my dilemma is one of the previous owners somehow used some kind of foam inserts on the far passenger-side mounting point to stop vibrations. There was a bolt there but it looks like the tried to weld it to the actual brace and not the head of the bolt... What was left of the bolt broke off when I tried to use a universal socket to attempt to grip what was left of the head of the bolt. Maybe they did it to make it look like the bolt was there? I'm afraid there is a hole under the foam and not just the broken stud of the bolt. The rest of the bolts look fine and intact. So the passenger side portion isn't mounted/secured. If the bolt is still there, I can drill the bolt to try to extract it.
The other issue I'm having is whether or not the suspension needs to be supported if I unbolt the brace.. There aren't any videos on the m37 or m37x for this replacement but there are for the g37 and g37x. I've read up on the people who did this job on the g37's and they just seem to unbolt the brace and install the new one.... I went to the dealer to consider getting them to do it..... and they claimed a lot needed to be done, including a 4-wheel alignment. What I find funny is that the service writers never seem to know what needs to be done, they have to ask the tech, and even then it seems iffy. The service writer initially mentioned something about having to loosen the engine mounts, to complete the job, and you know.... that wasn't it. Maybe he was thinking I was referring to the front subframe? I had them actually look at the car and now their telling me it will take 4 hours, the control arms will have to be supported, and the front suspension shouldn't be loaded... When you look at the control arms, specifically transverse link portion(where the brace mounts to), you can see that both are BOLTED TO THE FRAME OF THE CAR with two long bolts. And the two bolts on each side of the brace simply mount to the BOTTOM of each control arm(on the transverse link) and the bolts are rather short.. So I'm not understanding their logic. Am I missing something?
I don't want to attempt the job to have the control arms move too much and then I can't remount the bolts. Or have something fall... But I suspect I'm being lead to just spend money. Because I sourced the OEM brace and all 8 bolts myself because the dealer wanted $1,100 for the brace alone... I got everything for about $700 shipped and VIN matched. THEY WANTED OVER $1500 IN LABOR even though I will supply the parts. They said they wanted to quote high ,and no more than that, just in case they weren't sure but it could be a lot less.

Pictures of the passenger mount point of the batwing brace and the control arm(Transverse Link) are below:

[Ilya]

I replaced mine recently and had to have a shop weld a nut to one bolt cause I stripped it (damn NY car).

I purchased this one for my M56x, not sure if it's different for your M37x.

https://www.ebay.com/itm/276945011905

However, I recently learned that Z1 Motorsports developed one for the M (not sure again if it's only for V6 or V8 or both) that is likely lighter and looks better.

That being said, the swap (other than rusty bolt issues) was SUPER easy. Undo bolts, drop the batwing, replace. I did it myself, lowering it down on my chest. Used my knees/legs to hold up the other side when installing the first bolt (after that it was easy).

NOTHING else is impacted on the suspension. This thing is literally there to just give rigidity to the chassis, it doesn't support much if anything else.

I did this in my garage on my quickjack lift myself. Didn't need no stinkin alignment afterword's.

That stealership was tryin to take you for a ride.

Here is my facebook post about it: https://www.facebook.com/groups/infinit ... 741442111/ .

[Ilya]

Here is the OEM brace from Z1: https://www.z1motorsports.com/front-str ... 44781.html

Here is the G37x brace that supposedly fits our car from Z1: https://www.z1motorsports.com/chassis-r ... 72968.html

Here is the Facebook post about it alerting the M/Q community to it: https://www.facebook.com/groups/infinit ... 9484835077

[anewstartinchrist]

Here is the OEM brace from Z1: https://www.z1motorsports.com/front-str ... 44781.html

Here is the G37x brace that supposedly fits our car from Z1: https://www.z1motorsports.com/chassis-r ... 72968.html

Here is the Facebook post about it alerting the M/Q community to it: https://www.facebook.com/groups/infinit ... 9484835077

Thank you so much for the advice and clarification. I bought my brace from PartSouq VIN matched and used the part number 544B2EG300, which is the same one from Z1. The cost was about the same. I ended up getting 8 new bolts too. The dealer marks these parts up too damn much and thinks they're going to be able to sell them. SMH... So, what I'll do is do my best to get the car up in the air as much as I can and remove the current brace and then take a look at the passenger side mounting point to see what is going on. I pray all I have to do is extract a broken bolt... Otherwise it will have to be addressed at a body shop. My biggest problem is the vibration I'm feeling. It got worse today when driving it after having my independent shop fix a CV axel leak earlier this week. I don't think it's the front propeller shaft, but rather the main one in the rear(with the flex disk).

[emm3seven]

Interesting to see this post, and great info, as I'm about to dive into this same thing on my M37x.

Sharing my own approach...I had missed the Z1 option in my research since I bought parts before they released it, but I ended up going with the newer OEM part that is laid out here (544B2-JK51B):

https://www.youtube.com/watch?v=gNLTZFYERb8

To quote a blurb from the description:

The design was changed on the 2013 G37 to the one I used and continued on to the Q40 and newer Q50 platform. The newer brace is slightly heaver but much more solid and durable looking.

New style brace: 544B2-JK51B (top)
Old style brace: 544B2-EG300 (bottom)

I got the new style OEM brace for $450 shipped from Amayama (back in July).

Technically, Infiniti says this part is not for the M, but through some transitive cross-referencing it appears that it will work.

I have not yet installed the part, but will likely tackle it over the holidays. I'll post an update when I do.

[Ilya]

I didn't notice any difference on my car, I did it more out of precaution since mine was quite shot...but do it up, boys!

[anewstartinchrist]

I didn't notice any difference on my car, I did it more out of precaution since mine was quite shot...but do it up, boys!

Thanks man! I just saw that you're in Charlotte! I'm in the Piedmont Triad area. If this rain will stop I will hopefully attempt it this weekend. I think I'm going to prime and paint this brace before even putting it on, just to be sure lol. I'm doing my brace as a preventative too but notice the passenger side mounting point didn't have a bolt.

[anewstartinchrist]

Interesting to see this post, and great info, as I'm about to dive into this same thing on my M37x.

Sharing my own approach...I had missed the Z1 option in my research since I bought parts before they released it, but I ended up going with the newer OEM part that is laid out here (544B2-JK51B):

https://www.youtube.com/watch?v=gNLTZFYERb8

To quote a blurb from the description:

The design was changed on the 2013 G37 to the one I used and continued on to the Q40 and newer Q50 platform. The newer brace is slightly heaver but much more solid and durable looking.

New style brace: 544B2-JK51B (top)
Old style brace: 544B2-EG300 (bottom)

I got the new style OEM brace for $450 shipped from Amayama (back in July).

Technically, Infiniti says this part is not for the M, but through some transitive cross-referencing it appears that it will work.

I have not yet installed the part, but will likely tackle it over the holidays. I'll post an update when I do.

Aww man... I appreciate the feedback for sure. I already bought the OEM brace from PartSouq and new bolts. I wish I knew earlier about the Z1 option . My goal this weekend is to remove the old brace and see what damage there is on the passenger side mounting point for the brace. I pray there isn't a hole there . Just whatever is left from when the head of the bolt broke off when one of the previous owners had it. If you haven't already, check out my pictures in this post. I already bought an extraction kit and drill bits from Harbor Freight just in case.

[Ilya]

I didn't notice any difference on my car, I did it more out of precaution since mine was quite shot...but do it up, boys!

Thanks man! I just saw that you're in Charlotte! I'm in the Piedmont Triad area. If this rain will stop I will hopefully attempt it this weekend. I think I'm going to prime and paint this brace before even putting it on, just to be sure lol. I'm doing my brace as a preventative too but notice the passenger side mounting point didn't have a bolt.

Yep - my car was originally a FL lease car that ended up in NY where I had it for about 5-6 years (Albany area). I then moved to Tampa, FL during COVID and then up to Charlotte in August 2023. But the years in NY did a NUMBER on this car...so much rusted stuff. Damn salt.

[anewstartinchrist]

Thanks man! I just saw that you're in Charlotte! I'm in the Piedmont Triad area. If this rain will stop I will hopefully attempt it this weekend. I think I'm going to prime and paint this brace before even putting it on, just to be sure lol. I'm doing my brace as a preventative too but notice the passenger side mounting point didn't have a bolt.

Yep - my car was originally a FL lease car that ended up in NY where I had it for about 5-6 years (Albany area). I then moved to Tampa, FL during COVID and then up to Charlotte in August 2023. But the years in NY did a NUMBER on this car...so much rusted stuff. Damn salt.

Funny you say that because my car was sold out of NJ and spent the beginning of its life in PA up to about 45k miles, and then went to SC. So it got a taste of the salt. I've definitely got corrosion on the aluminum block and some superficial rust and peeling paint on the underbody. BTW, I took the crossmember off today. I did run into an issue with a rounded bolt. No telling who did that but thank God for Harbor Freight still being open this evening since Thanksgiving is tomorrow. I will post a picture of the broken bolt from the passenger side. It looks like the bolt is still there but someone attempted to weld a nut on and it DID NOT work. I will have to use a 1/4" drill bit on what's left and then use a 1/4" extractor bit. They had some kind of sticky foam padding there to insulate the brace to keep it from vibrating. I have been chasing this body vibration and can't seem to pinpoint it.

[anewstartinchrist]

This is the aftermath of the passenger mounting point when I removed the batwing and peeled off the sticky foam pads. I think I can drill this out and extract it. I will need to use Kroil 1st lol. I will probably sand the whole surface down, prime, and then paint it just in case. I plan on doing the same thing to rhe oem brace. Plus anti-seize on the bolts. Out of the 8 mounting bolts I had one that was rounded off. Thank God for the Icon kit from Harbor Freight.

[Ilya]

Gnarly.

[emm3seven]

I strongly recommend picking up an induction heater. You are likely in for a bad time without heat. I fought a similar sheared off bolt (holding on sway bar bushing bracket) over a two week period a couple of years ago, and when I finally pulled the trigger on the induction heater I had the bolt out in an hour. I now will proactively hit anything that looks rusty with the induction heater and PB before even touching it with a wrench.

Example here: https://www.amazon.com/dp/B0B5ZNJY79

To do the most good, you would need to sneak the coil up inside through a hole and heat it up from the back. But you could probably do something from the front with one of the wide flat coils.

Good luck!!

[anewstartinchrist]

I strongly recommend picking up an induction heater. You are likely in for a bad time without heat. I fought a similar sheared off bolt (holding on sway bar bushing bracket) over a two week period a couple of years ago, and when I finally pulled the trigger on the induction heater I had the bolt out in an hour. I now will proactively hit anything that looks rusty with the induction heater and PB before even touching it with a wrench.

Example here: https://www.amazon.com/dp/B0B5ZNJY79

To do the most good, you would need to sneak the coil up inside through a hole and heat it up from the back. But you could probably do something from the front with one of the wide flat coils.

Good luck!!

I appreciate the advice. I was very reluctant to use heat since this broken bolt is on the bottom side of the passenger side floor area, near the rocker arm. I didn't want to risk causing a fire and since I didn't have a bolt head to focus the heat on, my chosen method was to use lots of Kroil and sand the metal down and remove some of the weld they tried to attach a bolt head to. I WAS ABLE TO EXTRACT THE BOLT!!! Thank you Jesus! BUT not without a fight. I used the smallest of the Icon 15 piece extractor set at a 1/4" and drilled with a Hercules 1/4" drill bit first. This one I tried to hammer in first since it didn't initially bite. Man..... it snapped off! I freaked out and tried to drill it out but to no avail..... So I found my small picks and start to pry and move it around. And to my surprise, it fell out. I stepped up to a 5/32" extractor bit and drill the same hole with a 5/32" drill bit. This time, I started it by hand with a ratchet, and it was just enough to bite and it screwed out with ease. Lesson learned.. Next I am going to clean the area, then prime and paint it. Once I do that. I will clean out all of the bolt holes with a brass wire brush. Before installing the new brace, I will spray some antiseize in the holes.
Oh and I forgot to mention, I ended up sanding down the new brace with 120 grit. I primed and painted it, and cleaned it with SprayMax's Wax and Grease remover before priming it. Hopefully, it'll last. I will post a picture of the finished repair.

[anewstartinchrist]

I strongly recommend picking up an induction heater. You are likely in for a bad time without heat. I fought a similar sheared off bolt (holding on sway bar bushing bracket) over a two week period a couple of years ago, and when I finally pulled the trigger on the induction heater I had the bolt out in an hour. I now will proactively hit anything that looks rusty with the induction heater and PB before even touching it with a wrench.

Example here: https://www.amazon.com/dp/B0B5ZNJY79

To do the most good, you would need to sneak the coil up inside through a hole and heat it up from the back. But you could probably do something from the front with one of the wide flat coils.

Good luck!!

I appreciate the advice. I was very reluctant to use heat since this broken bolt is on the bottom side of the passenger side floor area, near the rocker arm. I didn't want to risk causing a fire and since I didn't have a bolt head to focus the heat on, my chosen method was to use lots of Kroil and sand the metal down and remove some of the weld they tried to attach a bolt head to. I WAS ABLE TO EXTRACT THE BOLT!!! Thank you Jesus! BUT not without a fight. I used the smallest of the Icon 15 piece extractor set at a 1/4" and drilled with a Hercules 1/4" drill bit first. This one I tried to hammer in first since it didn't initially bite. Man..... it snapped off! I freaked out and tried to drill it out but to no avail..... So I found my small picks and start to pry and move it around. And to my surprise, it fell out. I stepped up to a 5/32" extractor bit and drill the same hole with a 5/32" drill bit. This time, I started it by hand with a ratchet, and it was just enough to bite and it screwed out with ease. Lesson learned.. Next I am going to clean the area, then prime and paint it. Once I do that. I will clean out all of the bolt holes with a brass wire brush. Before installing the new brace, I will spray some antiseize in the holes.
Oh and I forgot to mention, I ended up sanding down the new brace with 120 grit. I primed and painted it, and cleaned it with SprayMax's Wax and Grease remover before priming it. Hopefully, it'll last. I will post a picture of the finished repair.

ROCKER PANEL, not "rocker arm"

[anewstartinchrist]

I figured I'd post the pictures of the tools/supplies I've used and the rest of the process so far. I've got to wait for the finish coat to dry before mounting the brace. The rain is holding me back but hopefully I will have this thing installed by Wednesday 12/3. I figured I'd show what the old brace looked like too.

[anewstartinchrist]

This is the finished job. I will probably spray this with some metal protector from Amsoil on my next oil change. Gotta keep this brace protected. There's a "Lifetime Guarantee" on the 15-piece ICON set so Harbor Freight replaced the entire set.

[Ilya]

Nice! Well done!

[anewstartinchrist]

Nice! Well done!

Appreciate it. For anyone who needs help in the future. The part numbers I used for my 2012 Infiniti M37x are below.

544B2-EG300 - Front Bar Assembly- Cross (Batwing)

11298-EG30A - Bolts (8 total)