$75 for reinforcment plate bolts and nuts?

[bmw540san]

I have starter on order as I identified the start up noise as starter disengaging to late. It'dsdefinitely not the TC guides as I've listened to quite a few noises of those.

I've read number of postings stating that bolts are one time use and have to be replaced since they stretch after initial torque. I've also read some postings that set costs about $30 which is not even close to current price.

Qty 6 - 31101096987 - bolts
Qty 6 - 33306760587 - nuts

Well, they're about $75 for 6 bolts and 6 nuts and that's about the best price out there. I was wondering if anybody has found high grade bolt that'd would do for less money.

I like to follow manufactures procedure but that's 50% cost of actual starter and while I'll buy them if I have to, I was wondering if there is a different solution.

Thanks in advance for any info.

[OptimusPriM5]

Originally Posted by bmw540san

I have starter on order as I identified the start up noise as starter disengaging to late. It'dsdefinitely not the TC guides as I've listened to quite a few noises of those.

I've read number of postings stating that bolts are one time use and have to be replaced since they stretch after initial torque. I've also read some postings that set costs about $30 which is not even close to current price.

Qty 6 - 31101096987 - bolts
Qty 6 - 33306760587 - nuts

Well, they're about $75 for 6 bolts and 6 nuts and that's about the best price out there. I was wondering if anybody has found high grade bolt that'd would do for less money.

I like to follow manufactures procedure but that's 50% cost of actual starter and while I'll buy them if I have to, I was wondering if there is a different solution.

Thanks in advance for any info.

Hey man I did this job last year and paid no where near the prices at the dealer now not sure why they have gone up so much...this is the PN I used which matches yours identically and taken from RealOEM. I usually save all my receipts and will verify but I did get them from the dealer for sure. Im guessing you can use the sizing in the description to match up the bolt but Ill leave that to the physics pro's on the site if it will work.

Ill also pull my records to see if I can find the prices I paid but think I was close to the $60-70 range IIRC.

04Hex bolt with washerM10X55631101096987$3.53
05Hex nut wiht flangeM10-10 ZNS3633306760587$0.78

[bmw540san]

Originally Posted by OptimusPriM5

Hey man I did this job last year and paid no where near the prices at the dealer now not sure why they have gone up so much...this is the PN I used which matches yours identically and taken from RealOEM. I usually save all my receipts and will verify but I did get them from the dealer for sure. Im guessing you can use the sizing in the description to match up the bolt but Ill leave that to the physics pro's on the site if it will work.

Ill also pull my records to see if I can find the prices I paid but think I was close to the $60-70 range IIRC.

04Hex bolt with washerM10X55631101096987$3.53
05Hex nut wiht flangeM10-10 ZNS3633306760587$0.78

There is no question they went up because I found your old prices when goggled the part# but when open any link it seems that everybody updated the prices to $11+ per each bolt.
I use this dealer and nobody touches their prices but even they come at $75 before shipping:
BMW Parts and Accessories

I'm not a cheapskate but I'm convinced I can find higher grade bolts and nuts than OEM for probably under $30 when bought form reputable online metric bolts store.

I suspect that astronomical price has something to do with limited stock quantities.

Thanks.

[David.X5]

The prices have gone nuts. They used to be $3-4 each, which was still pricey, but not worth the trouble of finding an alternative.

Those bolts are M10 x 55mm long. Grade 10.9. I think there is space for a slightly longer bolt - 60mm should be fine.

On McMaster-Carr, a M10 x 60mm flange-head cap screw in grade 10.9, Zinc plated to JIS standards, is $7.58 for 10. (part number 95735A661). This is 1.25 mm thread pitch, so you would have to pick a matching nut with the same thread pitch.

[bmw540san]

Originally Posted by David.X5

The prices have gone nuts. They used to be $3-4 each, which was still pricey, but not worth the trouble of finding an alternative.

Those bolts are M10 x 55mm long. Grade 10.9. I think there is space for a slightly longer bolt - 60mm should be fine.

On McMaster-Carr, a M10 x 60mm flange-head cap screw in grade 10.9, Zinc plated to JIS standards, is $7.58 for 10. (part number 95735A661). This is 1.25 mm thread pitch, so you would have to pick a matching nut with the same thread pitch.

That's exactly what is my plan. I suspected that 10.9 is plenty and I'm glad to see we think alike. While there are many occasions where following the OEM specs is the best way, this is clearly the case of extremely overpriced part.

I'm simply seeing no issues with using what you're suggesting and what I sort of had in my mind. It'd be a different story if the OEM bolts were some extremely precious material in astronomically high grade and exposed to extreme forces.

I'll check out the site you suggested. Thanks.

By the way, if anybody needs it, RockAuto has Bosch remanufactured starter with 2 year warranty for $140 shipped after discount. $65 for the core and after shipping back, total cost is probably around $150. I just bought mine there.

[oldskewel]

Originally Posted by David.X5

The prices have gone nuts. They used to be $3-4 each, which was still pricey, but not worth the trouble of finding an alternative.

Those bolts are M10 x 55mm long. Grade 10.9. I think there is space for a slightly longer bolt - 60mm should be fine.

On McMaster-Carr, a M10 x 60mm flange-head cap screw in grade 10.9, Zinc plated to JIS standards, is $7.58 for 10. (part number 95735A661). This is 1.25 mm thread pitch, so you would have to pick a matching nut with the same thread pitch.

Careful with changing thread pitch on these, or any bolts where torque is important.

The standard pitch for M10 is 1.5mm. If you change that to 1.25mm, the torque value and angle value will be different. The angle is easy to consider - 90 degrees on a 1.5mm pitch bolt will stretch the bolt by 0.25 * 1.5 = 0.375mm. On the 1.25mm pitch bolt, it will be 0.25 * 1.25 = 0.3125mm. The initial torque value will be different, but not so easy to analyze because that is dominated by friction.

There is nothing magic about these class 10.9 bolts BMW overcharges you for. During the torquing of the 90 degree angle, the bolt (and maybe nut) exceeds the yield stress and deforms plastically. This work hardens it, making it stronger (higher yield strength; not affecting the tensile strength), but not stiffer than when it was new. This "feature" is usually why TTY is used - you get the increased strength you want, but without increasing stiffness (e.g., when a certain amount of compliance is required).

So when you remove and reinstall them (like I do), you should NOT torque them and then apply the same angle as you would use on new bolts. If you do that, each time you R+R them you will be pushing further into the plastic region, eventually exceeding the tensile strength, at which point they will break, either while tightening them or when you're out driving.

Ideally, you would torque them back to their exact stretch before you removed them, but you do not want any further plastic deformation.

A completely different way to analyze this issue, not relying on engineering, would be to phone a few BMW dealers and ask how long it will take to get these parts in stock. My understanding is they don't stock them because they don't use them. They re-use the existing ones, thinking far less about it than I or others on this list have. I expect they'll do this until it causes a problem - and are still waiting for that to happen. It would be good to know what torque+angle procedure they follow on re-used bolts, but it should be different from that used for new bolts. Hopefully they know that.

[squidzilla]

We have a bolt and nut supply place here in SLC Utah that I can buy those from. There nothing more than a bolt that meets a spec so you can buy those from anywhere that sells that spec of bolt. I think I was quoted about 10.00 for all of them or so.

Here is they are if you do not have a similar place near you. Maybe you can ask them to ship them to you.

Bolt & Nut Supply Co.: Homepage

[TiAgX5]

These were around $20 when I needed them 2 yrs ago.

4 x price increase is unreal!

[axgordon]

The other option is to reuse old bolts. I expect many members here to disagree, but I asked few local BMW shops here in Maryland, and all of them just reuse these bolts. I reuse them myself after careful inspection. They assembled without a problem and I hope they will perform well is case of collision. By inspection i meant to check them the same way mechanics check head bolts - using caliper to insure that they were not stretched.

[bmw540san]

Originally Posted by axgordon

The other option is to reuse old bolts. I expect many members here to disagree, but I asked few local BMW shops here in Maryland, and all of them just reuse these bolts. I reuse them myself after careful inspection. They assembled without a problem and I hope they will perform well is case of collision. By inspection i meant to check them the same way mechanics check head bolts - using caliper to insure that they were not stretched.

My only concern with reusing them is that they're probably "tired" and more likely to snap, not necessarily during reinstalling but later on during driving. But, you just might be right about not worrying about them.

Just to play it safe I'll probably go with 10.9 grade M10X60 from Ace Hardware of all places. It's about $25 for 6 flanged bolts and 6 flanged nuts. I've checked online and some local places and $25 is about cheapest for 10.9 grade.

Obviously, I'll check first that 5mm extra is non to long but I'm almost certain that it's not.