SPL Parts Service Bulletin, Anyone ?......

[nicksm3]

Hey guys,
Who received this email from SPL? I got it a few days ago.
Has anyone addressed this issue? Any failures on track regarding?

https://www.splparts.com/tsb-2301/

[roastbeef]

there was some discussion about it in the chit chat thread. i haven't seen anyone post any failures.

someone posted up about a possible failure at laguna seca about a year and a half ago, but the car was wrecked and several suspension arms were broken, some of which were oem. hard to theorize what actually happened.

[nicksm3]

Originally Posted by roastbeef

there was some discussion about it in the chit chat thread. i haven't seen anyone post any failures.

someone posted up about a possible failure at laguna seca about a year and a half ago, but the car was wrecked and several suspension arms were broken, some of which were oem. hard to theorize what actually happened.

Got it! Thank you brother !

[gh0stE92M3]

Are they going to be providing replacement bolts to those affected or are they requiring people to purchase the new bolts?

[nicksm3]

Originally Posted by gh0stE92M3

Are they going to be providing replacement bolts to those affected or are they requiring people to purchase the new bolts?

Great question! and I will not be purchasing zilch! I’m
Hoping they will take care of it.

[rhyary]

I know about this issue :-(

[nicksm3]

Originally Posted by rhyary

I know about this issue :-(

Ahhhh shit! When did this happen?

[JobanM]

I live in Canada, and I have heard of few cars locally having the failure. It is scary, so I was able to buy the updated studs. I have since replaced the bolts which looked fine with the studs.

[nicksm3]

Originally Posted by JobanM

I live in Canada, and I have heard of few cars locally having the failure. It is scary, so I was able to buy the updated studs. I have since replaced the bolts which looked fine with the studs.

Oh man…You had to “buy”?
We shouldn’t have to buy anything if the part is prone to failure from the start and there is a Service Bulletin out.

[DRLane]

Originally Posted by nicksm3

Oh man…You had to “buy”?
We shouldn’t have to buy anything if the part is prone to failure from the start and there is a Service Bulletin out.

It’s prone to failure if not properly seated and torqued to spec. Checking and confirming on a routine basis is what they’re requiring to prevent failure. I doubt they will be giving away replacement studs.

[JobanM]

Originally Posted by nicksm3

Oh man…You had to “buy”?
We shouldn’t have to buy anything if the part is prone to failure from the start and there is a Service Bulletin out.

Yeah, I paid it out of my own pocket. Like DRLane said it's mainly for people to inspect that area. My bolts seemed fine after about 14 track days on them.

[Signature Wheel BMW]

I wanted to provide you with an update regarding the SPL service bulletin. The bulletin addresses issues with their previous bolt style, which tended to gall out due to insufficient torque, leading to infrequent but severe failures. As a precautionary measure, SPL has issued a service bulletin advising users to remove the bolts and inspect the threads for galling. If the bolts were torqued under 110 pounds, replacement is recommended due to fatigue.

Following the service bulletin guidelines, I removed and replaced my bolts with the new, albeit more expensive, stud design. However, the installation proved challenging (requiring 180LB of torque), and I'm uneasy about having a nut on both ends.

Considering reverting to the old bolt design, I encountered a flaw: the bolts were only 4 inches long, and the threads were damaged by the jam nuts upon removal. To address this, a friend suggested a solution: using 4.5-inch-long, highest-grade ASTM A574 bolts with the addition of a spacer for increased articulation (see arrow). Use the same number of spacers you had before above the bearing. A robust Grade 8 nylon nut was chosen for one end, and the entire thread was treated with copper antiseize. Torquing to 124 pounds (lubricated torque) and marking with a paint marker completed the process. Routine checks, including inspecting the marker, are now part of my pre-track weekend routine.

Black-Oxide Alloy Steel Socket Head Screw
5/8"-18 Thread Size, 4-1/2" Long ASTM A574 (equivalent to 12.9 grade)
https://www.mcmaster.com/91251A489/

High-Strength Steel Nylon-Insert Locknut
Grade 8, Zinc Yellow-Chromate Plated, 5/8"-18 Thread Size
https://www.mcmaster.com/97135A275/
Service Bulletin: https://www.splparts.com/tsb-2301/

SPL Studs = $73 shipped (I don't love this design)
My solution = $28 shipped, you can use these for other SPL arms and preventative every 3 track season. (proven SPL design, just longer and stronger bolts)

*This is based on my research and experience with hardware. I'm not responsible for damage if you follow my method. These ASTM A574 are stronger than SPL's Grade 8 original style bolts, and it's longer for more thread count.

[berns]

Originally Posted by Signature Wheel BMW

I wanted to provide you with an update regarding the SPL service bulletin. The bulletin addresses issues with their previous bolt style, which tended to gall out due to insufficient torque, leading to infrequent but severe failures. As a precautionary measure, SPL has issued a service bulletin advising users to remove the bolts and inspect the threads for galling. If the bolts were torqued under 110 pounds, replacement is recommended due to fatigue.

Following the service bulletin guidelines, I removed and replaced my bolts with the new, albeit more expensive, stud design. However, the installation proved challenging (requiring 180LB of torque), and I'm uneasy about having a nut on both ends.

Considering reverting to the old bolt design, I encountered a flaw: the bolts were only 4 inches long, and the threads were damaged by the jam nuts upon removal. To address this, a friend suggested a solution: using 4.5-inch-long, highest-grade ASTM A574 bolts with the addition of a spacer for increased articulation (see arrow). Use the same number of spacers you had before above the bearing. A robust Grade 8 nylon nut was chosen for one end, and the entire thread was treated with copper antiseize. Torquing to 124 pounds (lubricated torque) and marking with a paint marker completed the process. Routine checks, including inspecting the marker, are now part of my pre-track weekend routine.

Black-Oxide Alloy Steel Socket Head Screw
5/8"-18 Thread Size, 4-1/2" Long ASTM A574
https://www.mcmaster.com/91251A489/

High-Strength Steel Nylon-Insert Locknut
Grade 8, Zinc Yellow-Chromate Plated, 5/8"-18 Thread Size
https://www.mcmaster.com/97135A275/
Service Bulletin: https://www.splparts.com/tsb-2301/

SPL Studs = $58 (I don't love this design)
My solution = $28 shipped, you can use these for other SPL arms and preventative every 3 track season. (proven SPL design, just longer and stronger bolts)

*This is based on my research and experience with hardware. I'm not responsible for damage if you follow my method. These ASTM A574 are stronger than SPL's Grade 8 original style bolts, and it's longer for more thread count.

Gotta say... it's nice to do DIY's and provide info for the community, but you are talking about a major, critical piece of hardware. While there have been some issues with improper maintenance, torque, etc... SPL engineers are doing more than picking a part from McMaster and heading to the track. I don't think you coming in with your own DIY solution to save a few bucks or make you (not an engineer) feel better, is the right move. Leave it to them. They are liable.

[Signature Wheel BMW]

Originally Posted by berns

Gotta say... it's nice to do DIY's and provide info for the community, but you are talking about a major, critical piece of hardware. While there have been some issues with improper maintenance, torque, etc... SPL engineers are doing more than picking a part from McMaster and heading to the track. I don't think you coming in with your own DIY solution to save a few bucks or make you (not an engineer) feel better, is the right move. Leave it to them. They are liable.

BMW engineers with hundreds of million of dollars budget designed OEM rod bearings too. Do people still run OEM rod bearings, a major critical piece of hardware?

The previous SPL bolts are 4" Grade 8 bolts 1/2 drive 5/8 diameter, which I love the ease of install and didn't really have issues with other than it slightly bent after 1.5yrs with track use. I honestly would run the OG bolts again vs the new studs if I didn't find a stronger / longer bolts solutions.

These are almost identical to the OG bolts but 4.5" long, Grade 12.9 (which is higher than grade 8), 1/2 drive 5/8 diameter. The OG bolts worked just fine, some reported bending and very rare reported breaking due to under torqued. The solution I'm providing to the community is just the OG exact design, but stronger and longer to accommodate nylon lock thread nut. Part of the OG bolts failure was the jam nuts galling the treads, causing a weak point.

Just to give you an idea, these 12.9 grade are at 170,000 psi tensile strength. 12.9 grade are in the same class as MSI and high end racing wheel studs.

I'm not reinventing what SPL did, I just found a better and stronger solution. I love the SPL OG bolts design, I don't love the new studs design that I installed and threw it away after 3 weeks. These 4.5" 12.9 grade bolts already used and proven on track on the SPL LCA.

You're saying the obvious, of course with any mods, do it at your own risk. If you take a modified car on the race track and you had a bad day due to parts failure, good luck pointing the blame on the suspension part manufacturer. That's what track insurance is for.

Regarding McMaster-Carr. See photos below of the 4" black oxide 12.9 grade vs SPL OG 4" stainless grade 8. I doubt SPL makes their bolts in house as that requires a steel foundry etc, they most likely outsource and there's not too many bolts manufacturers in the world. McMaster-Carr is just a supplier.

[roastbeef]

i don't see what the difference is between the stud spl is suggesting and using 12.9 hardware... maybe i'll shoot them an email.

[Signature Wheel BMW]

Originally Posted by roastbeef

i don't see what the difference is between the stud spl is suggesting and using 12.9 hardware... maybe i'll shoot them an email.

This is from the service bulletin: https://www.splparts.com/tsb-2301/

"Description of Issue: SPL has received inquiries regarding bending and failures of cap bolts used in SPL front lower control arms. Information supplied to SPL indicates inadequate or un-retained torque of retaining nut/bolt to lower control arm may be contributing to bending and fatigue of grade-8 fasteners."

I have no issues with their OG style Grade 8 bolts, other than slight bend after 1.5yrs tracking and the thread are galled from jam nuts. All I did is upgraded to 12.9 (ASTM A574) and longer so I could use a nylon lock bolts. That fixes both issues: Grade 8 bolts bending and jam nuts galling the threads.

I'm sure the studs are fine, but I don't like them and threw them away after 3 weeks on my car. Just for the record, I like SPL's products and services. Hell, I have every single SPL part number on my car. I just wanted to source better mounting hardware than what they had for ease of install and pre-track inspection.