Toyota Bolt Head markings

[B1NZ]

Hi there, does anyone know if the factory toyota seat bolts are up to the 8.8 standards, a new regulation for MSNZ says that all seat bolts have to be up to this standard,

My factory AE92 seat bolts have two lines or dashes on the head one at 12 o clock and one at 6 o clock, I have googled and cant find a definant answer apart from all toyota bolts are apparently made to ISO 8.8 or higher and that they might have thier own special bolt marking codes.

Does any one have any relevant information or links? Thanks in advance

Brendon

[sergei]

Look here (page 14) http://abraxxa.zorro.at/files/ST205%203S-GTE%20(rev3)%20engine%20supplement%20RM398E.pdf

Although it is for torque settings and not grading.

[Leon]

is the link about the tensile str of the seat bolts in a Corolla?

[sergei]

is the link about the tensile str of the seat bolts in a Corolla?

That is a link to ST205 repair manual, the page 14 describes what the markings are. They are the torque specifications, which is not really grade of a bolt, but gives an indication.
As far as I am aware the markings on the bolt heads are standard across all Toyota models.

[sergei]

[B1NZ]

So according to the diagrams they are 6T, does this mean it is ISO 8.8 or higher?

[Quint]

i've never heard of a 6T bolt, though i know the markings you're talking about, often scratched my head about it.

8.8 has a yield stress of 635Mpa, so ah, get a big torque wrench and see if you can crank one up to 630Nm

[sergei]

http://www.cncexpo.com/MetricBoltTorqueNm.aspx

Say the bolt is 8mm/1.25mm from the chart above, max lubed torque for 8.8 grade is 19.1, which falls where the 6T is specified. But if Toyota meant dry torque, then you need 7T bolt.


Here is another chart:
http://www.finaldrives.eu/PartsBoltTorque.htm

if the bolt is 10mm/1.25mm from chart above, you need 7T bolt ( the chart does not specify lubed or dry).

Saying that, I don't know what headroom Toyota leaves when they specify maximum torque settings for their bolts.[/quote]

[sergei]

i've never heard of a 6T bolt, though i know the markings you're talking about, often scratched my head about it.

8.8 has a yield stress of 635Mpa, so ah, get a big torque wrench and see if you can crank one up to 630Nm

635Mpa does not equal to 630Nm . Of course if you have M39, then perhaps it will (didn't run calculation, so don't quote me on that).

[blindnz]

Would be intresting to get a comparison between these markings and SAE or Iso markings

http://www.google.co.nz/url?sa=t&rct=j&q=saej429%20to%20iso&source=web&cd=1&ved=0CFEQFjAA&url=http%3A%2F%2Fwww.fastenersolutions.com%2Fimages%2Fastm.pdf&ei=oEL7T9jcM7GkiAfF5KTqBg&usg=AFQjCNH8TA8-4Ams2K79O1xGqeqRkwGF5w

That gives you the sae grades,iso grades and markings. Yet these markings are different still

[B1NZ]

Sorted by buying $46 worth of bolts today so there is no banned car at events

[85AW20v]

According to the video link below, the bolts with three radial lines are the same as 8.8 grade. The chart on the page also verifies it when you look at the specs in the right hand columns.

http://www.nutsandbolts.com/v1-bolt-grade-markings.html

[Grrrrrrr!]

UNC/UNF bolt markings are not the same as metric automotive bolts