good quality tow hooks

[flyingbrick]

They are 4WD TERRAIN TAMER brand. ( http://www.terraintamer.com/ ) purchased in Hamilton.

[KiwiBacon]

They are 4WD TERRAIN TAMER brand. ( http://www.terraintamer.com/ ) purchased in Hamilton.

That's identical to one of the ones I have. Same thing is sold under a lot of different brand names. Your one has the half inch bolts but there are metric versions too.

[flyingbrick]

Where is the popcorn smile.

dammit!

OK back to hooks. Is it normal for these hooks to come with grade 5 bolts? I'd have thought that they would be supplied with the required bolts- but apparantly i have to go and get grade 8 or 10 or something now?

No big deal- just wondering if perhaps some manufactuers are selling a better product than others etc.

[coxsy]

go to EDL fasteners and buy some 8.8 ones and nylocks they are cheap enough

[Bulletproof]

Where is the popcorn smile.

dammit!

OK back to hooks. Is it normal for these hooks to come with grade 5 bolts? I'd have thought that they would be supplied with the required bolts- but apparantly i have to go and get grade 8 or 10 or something now?

No big deal- just wondering if perhaps some manufactuers are selling a better product than others etc.

You are looking at 2 different grading systems 1 imperial and the other metre ,so a grade 5 imperial is OK.

On toyotas Landcruisers and Hilux they come out using the japanese grading and use a 7 which is still stronger than an 8.8 metric so you need to know which grading you using to make sure the bolts are right.

Cheer Richard

[albundy]

On toyotas Landcruisers and Hilux they come out using the japanese grading and use a 7 which is still stronger than an 8.8 metric so you need to know which grading you using to make sure the bolts are right.

With that being said Richard, why is it that clubs in their infinite wisdom, refuse to allow grade 7 bolts to fix tow hooks? Is it ignorance as when I had my Terrano first checked for CLROC I was told to chjange the bolts despite me producing information that stated what you have just said.
Al

[Heath]

I guess it depends on who is looking at the regulations in the club. If the regs say 8.8 and they dont see that on the bolt (not knowing what the lines mean) and you say it is a 7 they will automaically deduce that it is weaker and cover their ass by saying use the 8.8. I guess the best thing to do is when the next AGM comes up put in a remit to have the grades of bolts (and whatever else) put in both metric and imperial in the rules.

I agree it's an ass sometimes when you know what you are saying and the person checking doesnt believe you (WoF are a perfect example - we sometimes know more about the regs than the testers). Unless you can get them to agree and you can show them exactly where it says it is okay the tester/inspector will dissagree and demand you change to what is written on their page.

[rangimotors]

I think clubs follow that rule because alot of them have no idea if a bolt is metric or imperial from just looking at its head all they are looking for is the number stamped on top.

[Sadam_Husain]

I think clubs follow that rule because alot of them have no idea if a bolt is metric or imperial from just looking at its head all they are looking for is the number stamped on top.

Its a bit like using the philosphoy of the dummys guide:
A 10000lb rated hook is ok coz its got 10000lb stamped on it
A rated 8000kg strop is ok coz its got a 8000kg tag on it
A 8.8 bolt is ok coz its got 8.8 stamped on it

Its makes it an easy way of assessing shit without being a qualified engineer and having to argue all the finer points of life till the cows come home or untill you end up in a big punch up

[Bulletproof]

Another thing too, most imperial 5s and Japanese 7s are automotive bolts that have a fine thread and are easier to torque up properly, whereas most metric 8.8s are engineers bolts with a coarse thread making them harder to get accurate torque settings.
Most 4 wheelers that I have seen use the 8.8 with the coarse thread instead of the fine thread. They are also 12mm which leaves clearance of .75 mm.
I spent a number of years in the heavy truck industry and all chasis bolts are fine thread.

I use imperial half inch grade 5 for these 2 reasons.

1 they are 12.7mm and fill the hole better
2 they are easier to tighten properly with the fine thread.

Thats only my opinion

Cheers Richard

[coxsy]

them buy metric fine threads

[vvega]

also remeber to lube the threeds and friction surfaces when setting the tension or you will be fighting the friction not tightning the bolts

wayne

[Heath]

I think clubs follow that rule because alot of them have no idea if a bolt is metric or imperial from just looking at its head all they are looking for is the number stamped on top.

Its a bit like using the philosphoy of the dummys guide:
A 10000lb rated hook is ok coz its got 10000lb stamped on it
A rated 8000kg strop is ok coz its got a 8000kg tag on it
A 8.8 bolt is ok coz its got 8.8 stamped on it

Its makes it an easy way of assessing shit without being a qualified engineer and having to argue all the finer points of life till the cows come home or untill you end up in a big punch up

Exactly

[4WDbits]

If the tow hooks have imperial sized holes, use imperial size bolts - UNF if you want fine thread.
Metric and metric, fine thread if you like. Most automotive bolts are fine thread.
Its important that bolt sizes match bolt sizes as it prevents undue movement. Even if a bolt is torqued down correctly, if the bolts are the wrong size for the hole there will be movement, which leads to looseness, which starts a downward spiral leading to failure.

[flyingbrick]

The supplied bolts are quite loose in their holes already.

Considering M14 bolts and reaming the holes out.

[wopass]

i just use big ass cap screws. hard to argue with a cap head that has 12.9 on it eh

[T-Boon]

http://www.ccvc.org.nz/CCVC-SAFETY-0002 ... 050803.pdf

Found this doccument, the pictures might help.

[coxsy]

a good standard to go by

[albundy]

I use imperial half inch grade 5 for these 2 reasons

As a CLROC member your lucky you live in Nelson and don't have your trucked checked every year by the safety officer, you would not pass. I have been failed for having imperial bolts in tow hooks, despite having the literature to prove they where the correct bolts. Put the metric ones in just to satisfy someones poor knowledge base, then swapped them when I got home.
Al

[KiwiBacon]

i just use big ass cap screws. hard to argue with a cap head that has 12.9 on it eh

That's the best plan.

Two M12 cap screws at 135Nm each won't slip until after your 10,000lb rated hook has stretched and straightened.
Of course the clamping load from two M12 cap screws requires some serious size crush tubes (25-30mm OD) through the chassis and then enough surrounding metal to transfer the loads from those crush tubes through to the chassis steel.

[vvega]

o 12mm diameter Grade 8.8 or 10.9
o 1/2 inch Grade 5 or 8
o Must have nylock nuts or spring washers under the nuts
o NO cap screws

some rules make no sence
but i guess its only one club .. i hope there not all like that

[Moriarty]

o 12mm diameter Grade 8.8 or 10.9
o 1/2 inch Grade 5 or 8
o Must have nylock nuts or spring washers under the nuts
o NO cap screws

some rules make no sence
but i guess its only one club .. i hope there not all like that

Wonder why the NO CAPS clause?
Anybody know?

B

[KiwiBacon]

Wonder why the NO CAPS clause?
Anybody know?

B

At a guess, someone figures they're brittle because they're soo hard. Without working out that the force needed to crack one of those off would have your hook straightened and your chassis pulled into a diamond shape.

[flyingbrick]

Wonder why the NO CAPS clause?

Because ITS THE SAME AS YELLING

[Jezza]

Wonder why the NO CAPS clause?

Because ITS THE SAME AS YELLING

lol

Heres my weekends damage and a good example of why tow hooks should be mounted properly

[Moriarty]

Wonder why the NO CAPS clause?
Anybody know?

B

At a guess, someone figures they're brittle because they're soo hard. Without working out that the force needed to crack one of those off would have your hook straightened and your chassis pulled into a diamond shape.

Yeah, KB, they are certainly NOT the weak point. I am probably wrong, it's been happening like that lots this last few months, but I was under the impression that the hook was the weak point? designed to straighten at a certain tractive effort?

The YELLING answer was quite good too.

B

[T-Boon]

Wonder why the NO CAPS clause?

Because ITS THE SAME AS YELLING

Haha, awesome

And the damage above looks a bit messy, but at least nothing let go.

Guessing it was a snatch on an angle ?

[rangimotors]

Wonder why the NO CAPS clause?
Anybody know?

I have heard that its because the head can fill up with mud etc and corrode causing it to snap off in time.

[KiwiBacon]

Wonder why the NO CAPS clause?
Anybody know?

I have heard that its because the head can fill up with mud etc and corrode causing it to snap off in time.

Everything on a 4wd is subject to corrosion and needs checked periodically, don't see why cap screws would be worse than anything else.

[SMOKEY]

I got picked up by one of the well meaning clipboard carrying club volunteers at an event , My high grade CAT bolts where not listed on his rule sheet . When I presented CAT bolt documentation he went and got a more senior club member who then on closer inspection said that he could not pass my vehicle as the threaded part of the CAT bolt didn't show enough thread protruding through the CAT matching nut . After he and his mate walked off chuckling that they where once again correct in there assessment of my poorly engineered and attached tow hooks, I removed the lock nut that was fitted to give the thread some protection and after much persuasion got the senior club member to re-check the attachment , his answer was If I had longer bolts with me why hadn't I fitted them in the first place and then proceeded to give me a lecture on wasting his precious time .

IT'S HARD TO ARGUE WITH SOMEONE WHO HOLDS A CLIPBOARD,

FITZY.