I'm about to change the front pads and disks on my Golf, something I haven't got my hands dirty doing since I had my MK4 13 years ago.
Anyhow my general question is about the use of torque wrenches, when I looked up the pad and disk change on YouTube most of them were from the US.... boy they are obsessed with torque settings!
Even for the smallest thing they want to know the torque specifications (they also hate reusing bolts of any kind).
For most of my work I would tighten a nut until it was 'tight', how important are torque settings for regular car maintenance?
If I do invest on one any recommendations for a make?
Looking on eBay there seems to be a lot of 'cheap' ones but also a load made by Norbar (seem to be army surplus), are torque wrenches reliable? should I buy new or used?
Or do I just stick to a spanner?
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For some belts such as timing it'd be a good idea. I can't really think of anything else you need it for, top nuts on suspension assemblies. Perhaps a few others but not many. Car part torque setting normally have a very wide range +/- so I wouldn't worry too much.
Norbar are a good make if you want to get one, I've used them for years. You can get a 2nd hand one, the MoD surplus ones will have been checked every 3 months. So if they are a good price can get one if you want.
I wouldn't bother I've never really used them on cars.
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I am a tad OCD about such things. But only on critical components. You never hear the cacophony of clicking torque wrenches when you pass a workshop unless its something like wheels or cylinder heads.
You can often tell when you undo something the scale of tightness right up to VFT for driveshafts.
When I'm doing brakes I have used a torque wrench for the caliper mounting bolts. But do you know Ive also recently done some without and they haven't come adrift. Sometimes you cant even get a torque wrench in there so you have to revert to Plan 2.
The caliper to hub are fairly tight and the the sliding caliper bolts are lightly tight
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I am not at all technical but a forum related to my car goes on about the stretch bolts which are used somewhere in the brake assembly, and how you ought not re-use them.
I guess that's why torquing is important.
You may want to have a Google for stretch bolts to understand more.
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The use of a torque wrench is important but more to the point the correct use of a torque wrench.
We had a situation a few years ago at work where we 'lost' the double wheels on tractor units at an alarming rate over a few months.
We were extremely lucky that none did any damage and being aware of what could have happened, a team of technical experts were called in to observe and investigate the cause of the problem.
Their conclusion was that wheel nuts were being tightened with an air gun prior to torquing and tightened too tightly by both our fitters and the Tyre company fitters we use on contract.
This meant the nuts were already over tightened so the torque wrench 'broke' as soon as it was applied.
This practice was stopped and we haven't lost a wheel in the last 5 years.
Pat
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It's a practice you see often at garages, makes using the torque wrench pointless. A good example though of there being more failures from over-tightened rather than under.
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Many thanks everybody.
It's one of those tools that I 'think' I should have as part of a good tool kit but never got round to buying one.
I think I've found one to cover the middle range of torque settings so I might go for the MoD Norbar one, selling for about £15, something else to play with.
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When I had to do the caravan brakes a year or two ago, I was faced with using one-shot nuts that retained the drums. The tightness to deform the nut and hold it in place exceeded the capacity of my torque wrench. Never mind VFT, this was insanely tight.
I bought one of these.
www.machinemart.co.uk/p/040215238/
It turns any 1/2" drive ratchet or bar into a torque wrench. I found it easy to use but I don't know if it will suit a Golf brake job.
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Always surprised and sort of bothered me when places like Kwik Fit tightened wheel bolts with the torque driver and then used the torque wrench at the end.... well it's already over tightened. No wonder it can be hard to take off a wheel at the roadside. Which is why I have an extra long wheel brace.
Last edited by: rtj70 on Sun 14 Oct 18 at 18:57
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Stretch bolts are a special case I think, and it really would be foolish to re-use old bolts or not torque properly.
But I've always reused "ordinary" nuts and bolts, unless replacing because of worn flats.
It's usually vital to use a torque wrench on a cylinder head and to follow the correct sequence. Sometimes the specification is to go round once to an initial setting, then again to a higher setting, and finally to re-check in the correct sequence after 100 miles or so of running.
It's often said that spanners are the lengths they are precisely as a guide as to how much to tighten the nuts.
Bolts on brake components often use a kind of hardening Locktite, so they don't need to be super-tight but do take a lot of torque to undo. In fact I find a torque wrench most useful for undoing very tight nuts and bolts, because of the ability to exert a long slow pull without risk of breaking something.
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>> Always surprised and sort of bothered me when places like Kwik Fit tightened wheel bolts
>> with the torque driver and then used the torque wrench at the end.... well it's
>> already over tightened. No wonder it can be hard to take off a wheel at
>> the roadside. Which is why I have an extra long wheel brace.
I am quite happy that tyre fitters use a calibrated airgun set to the right torque, Im not quite so happy its the same one I see them throwing on the floor after they use it.
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>> I am quite happy that tyre fitters use a calibrated airgun set to the right torque,
It didn't fill me with much confidence at my local ATS when the young lad was struggling to undo my wheel bolts with his windy gun. I had to mention that it might help if he set the gun to undo the bolts instead of trying to do them up and strip the threads!
I'm sure there are tyre fitters out there that rely on the following method for doing up the bolts.
image.ibb.co/dM8PJ0/wheel-torque.jpg
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I bought mine from Lidl. Excellent quality, always use it on wheels.
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>> always use it on wheels.
I think you're meant to use it on the bolts/nuts ;)
Regarding whether to torque or not, it depends what I'm doing.
Something like a cylinder head, or wheel bolts, then yes.
Having used a few spanners in my time, I seem to have a sixth sense for how tight something should be. Whether that be just nipped up (for small bolts), or FT (for large bolts).
Last edited by: VxFan on Mon 15 Oct 18 at 10:30
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I have the lidl one, nothing fancy but very good,
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Your brakes fail, and you kill somebody. You are in court.
"So, Mr Rudedog, who last changed the brakes?"
"I did."
"And did you do it all in accordance with the manufacturer's advice?"
"Errrr...."
[Prison door clangs.]
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>> [Prison door clangs.]
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Has that ever happened? The only case I can remember was a medical student who did a wheel bearing up too tight. Car crashed and another student died. Police didn't prosecute the owner.
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The prognosis here was that the rear caliper bolts had come undone, the caliper come loose and taken out his wheel spokes.
The BMW recommendation is 'one shot' bolts and thread lock.
www.youtube.com/watch?v=HsdHDZVYTjk
Last edited by: Fullchat on Mon 15 Oct 18 at 12:24
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>>Has that ever happened?
No idea. Do you want to be the test case?
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To torque or not? - sooty123
