WTB: Toby Tabs

[sphiend]

If anyone has some never installed Toby Tabs they would be willing to part with, please PM me. Losing confidence that these are coming back. I am aware of the other options.

[Morpheus]

I was told they are coming back as well, starting to doubt it.

[dvonk]

i hope they are... :frown:

[Nicholas R]

I went with the 12.9 grade from fastenal. If Toby Tabs ever do come back I'll happily swap them out.

[sphiend]

I was told they are coming back as well, starting to doubt it.

Looked promising a year or so ago but crickets for a while now. Guess the price was not right.

[BTTF-1]

Any updates on these?

Ed:eek5::tantrum::eek5:

[sphiend]

Any updates on these?

Ed:eek5::tantrum::eek5:

Not that I have seen.

[1batt4u]

Tabs for what?

[Dangermouse]

TAB = Trailing Arm Bolt

[1batt4u]

Ok lol!

[1batt4u]

No one else has them, or they were good quality or something?

[Dangermouse]

He made a superior batch from Inconel that are much desired by owners. Do a search on Toby or Inconel and you will find some threads about them

[1batt4u]

If Toby if offering them, then I know they have to be great quality!! Thanx!!

[DCUK Martin]

After Toby stopped selling them, I had 12.9 bolts with Geomet coating made.

[elfking]

I just installed the set I got from Martin, great stuff..
Right sizes,lengths and ready to go... Lucky enough for me my old ones came out without too much trouble... Better then what I was reading about anyways!

[Nicholas R]

Just FYI, NOS TAB's are 10.9 grade M12x130mm bolts.

You can get grade 12.9 bolts through Fastenal with a variety of different coatings. I went to a Fastenal in my town and they got them in the next day. cost me less than $5 for the pair.

[DeLorean03]

Without stirring up too much of a fuss, I just want to state that DMCMW changed out my TABs just this summer - 31 year old bolts (That I am aware of), and they were a tad bent, but they weren't "in danger" of breaking by any means.

It is COMPLETELY subjective on the history of your car and how the PO's treated it before you bought it, but for the record, mine were 31 years old and were in decently good shape. Now the TAB bushings were a whole other story...

[DCUK Martin]

You can get grade 12.9 bolts through Fastenal with a variety of different coatings. I went to a Fastenal in my town and they got them in the next day. cost me less than $5 for the pair.

Allen head bolts, or originaly hex-heads? It's also very important not to get electroplated bolts without ensuring they've gone through a de-embrittlement process.


they were a tad bent, but they weren't "in danger" of breaking by any means.

For a 10.9 bolt to have yielded, it must have exceeded 90% of its ultimate tensile strength. Let me say that again - a force has been put through that bolt which puts it within 10% of the force required to break it. In the context of the TAB, it'll get loose which in turn subjects it to greater bending stresses. It's a vicious cycle and a very real design flaw in the car.

Given the number of original bolts out there that bend but do not break, we can conclude (crudely) that the forces "seen" by those bolts are in the 900-1000 MPa range. Hopping up to a 12.9 bolt gives you a 20% headroom. A Toby TAB is in a class of its own....!

[Nicholas R]

Allen head bolts, or originaly hex-heads? It's also very important not to get electroplated bolts without ensuring they've gone through a de-embrittlement process.



For a 10.9 bolt to have yielded, it must have exceeded 90% of its ultimate tensile strength. Let me say that again - a force has been put through that bolt which puts it within 10% of the force required to break it. In the context of the TAB, it'll get loose which in turn subjects it to greater bending stresses. It's a vicious cycle and a very real design flaw in the car.

Given the number of original bolts out there that bend but do not break, we can conclude (crudely) that the forces "seen" by those bolts are in the 900-1000 MPa range. Hopping up to a 12.9 bolt gives you a 20% headroom. A Toby TAB is in a class of its own....!

I disagree with this Martin. The argument the bolts are bending due to a force exceeding 90% of their tensile strength implies that the bending happened instantaneously. Nearly every trailing arm bolt removed has some bending to it, meaning every car would have to be regularly subjected to these forces. If this was the result of these excessive loading conditions, we would see more failures. A bolt cannot be repeatedly brought to 90% of it's ultimate strength, to the point of yielding, and not suffer from fatigue. The fatigue would destroy the bolts, especially over 30 years. If this were the case we would be seeing FAR more TAB failures. Plus hitting something in the road that would exert a force 10% greater is not difficult, yet we dont see these failures.

There are far too many cars with very different backgrounds that still tend to have the same bending. I think it's far more likely that the bending we see in the bolts is due to creep. 30 years loading would do that easily. That's not to say that it's not a concern, but I also do not believe that owners are regularly within 10% of breaking a TAB. There are way too many potholes, railroad crossings, road debris out there to not see failed TABs everywhere.

Also the 12.9 grade bolts I got from fastenal are not hex head, they are allen head. I'm not sure if that's a drawback or not. I used a breaker bar attached to an allen head socket to hold the bolt in place and tightened the nut on the other side during installation.


EDIT: On a side not, has anyone ever considered contacting ARP? They make custom bolts all the time for automotive applications. Because of my flywheel offset, I almost had to have them make me custom M11 bolts. I ended up finding suitable bolts elseware but I have heard really good things about them.

http://arp-bolts.com/

A quick look through there catalog showed these options for materials:
For reference, yeild strength and tensile strength of grade 10.9~135,000psi and 150,000psi; and grade 12.9~160,000psi and 175,000psi
http://img600.imageshack.us/img600/8282/arpmaterials.jpg

I have no idea what the cost would be but it's certainly an option.

[Rich]

Nearly every trailing arm bolt removed has some bending to it, meaning every car would have to be regularly subjected to these forces. ..... I think it's far more likely that the bending we see in the bolts is due to creep. 30 years loading would do that easily.

I can't offer any statistics saying that nearly every original TAB removed has some bending to it or not. I can offer one bit of data and a comment about metal creep.

Data - I pulled the OEM TABs off our D after 25 years and about 50,000 miles just to see them and put new ones in as a precaution. They were both as straight as could be. No cracks, no corrosion, no problems.

Creep - Yes, metals like steel alloys will yield in creep with a constant force that is high enough. No, since the load on the TABs with the car at rest is very, very low it's unlikely that creep is what kills TABs. The main force seen by a TAB is rearward when its wheel hits a bump or pothole. Secondary TAB force is from braking. Cornering loads go mainly to the upper and lower links. Jounce and rebound plus deadweight is taken up via the spring/shock.

My educated guess about TAB bending is that it has mostly to do with high speeds over rough roads. And weak OEM TAB specs....

[easy now]

I disagree with this Martin. The argument the bolts are bending due to a force exceeding 90% of their tensile strength implies that the bending happened instantaneously. Nearly every trailing arm bolt removed has some bending to it, meaning every car would have to be regularly subjected to these forces. If this was the result of these excessive loading conditions, we would see more failures. A bolt cannot be repeatedly brought to 90% of it's ultimate strength, to the point of yielding, and not suffer from fatigue. The fatigue would destroy the bolts, especially over 30 years. If this were the case we would be seeing FAR more TAB failures. Plus hitting something in the road that would exert a force 10% greater is not difficult, yet we dont see these failures.

There are far too many cars with very different backgrounds that still tend to have the same bending. I think it's far more likely that the bending we see in the bolts is due to creep. 30 years loading would do that easily. That's not to say that it's not a concern, but I also do not believe that owners are regularly within 10% of breaking a TAB. There are way too many potholes, railroad crossings, road debris out there to not see failed TABs everywhere.

Also the 12.9 grade bolts I got from fastenal are not hex head, they are allen head. I'm not sure if that's a drawback or not. I used a breaker bar attached to an allen head socket to hold the bolt in place and tightened the nut on the other side during installation.


EDIT: On a side not, has anyone ever considered contacting ARP? They make custom bolts all the time for automotive applications. Because of my flywheel offset, I almost had to have them make me custom M11 bolts. I ended up finding suitable bolts elseware but I have heard really good things about them.

http://arp-bolts.com/

A quick look through there catalog showed these options for materials:
For reference, yeild strength and tensile strength of grade 10.9~135,000psi and 150,000psi; and grade 12.9~160,000psi and 175,000psi
http://img600.imageshack.us/img600/8282/arpmaterials.jpg

I have no idea what the cost would be but it's certainly an option.

Thank you for disagreeing, aka real world

[easy now]

Smart people do things,