Torque limiting extensions help prevent over tightening fasteners with an impact to help save time. I’ve seen some go as low as 30 ft lbs. I know they are typically used for tires though. Most sets start at 65 ft lbs, and go up over 100. I’ve seen some that are well over 500 ft lbs.
Has anyone tried using this tool for something other than lug nuts on an automobile? The low torque variants seem to have some applications on fasteners other than lug nuts. However at what seems to be a standard length of 8 inches, it would seem that these tools would have limited use to fasteners other than lug nuts. What is the purpose though of these low variant torque limiting extensions (30 ft lbs to 60 ft lbs for example) if not for lug nuts?
I know there are stubby (4 and 3/4 inch) ones from Lisle, but only at 80 ft lbs and 100 ft lbs. There doesn’t seem to be torque limiting extensions smaller than this in overall length.
Why do companies not make this tool, except in smaller in overall length?
It would seem for example, a caliper bracket bolt rated to be tightened to 80 ft lbs, using a impact driver, an 8 inch torque limiting extension and a socket, would add so much length to your fastening tool, that may it be unfeasible to use to tighten the bolts down because of clearance issues. Having to resort to the lengthy process of using a ratchet to snug the bolt down and a then torque wrench to tighten it to specification. If you could just use a 80 ft lb torque stick with an impact, this would be a much faster process.
I also have a question. If I used additional extensions (not torque limiting) plus a torque limiting extension, would this still limit the torque to the appropriate value?
Say for example
socket + extension (not torque limiting) + extension torque limiting 80 ft lbs + impact
Would the torque on the socket still be limited to 80 ft lbs with the additional extension (not torque limiting) in-between the torque limiting extension and socket. Say for example the top bolt on a motor mount at the front of the vehicle, need some extra length for your unfastening/fastening tool or unfasten other parts of the vehicles to get to it. On my car this bolt is 64 ft lbs. A 60 ft lb torque limiting extension would get me close, and then tighten further down with a torque wrench, or could just use a 65 ft lb torque limiting extension and not worry about the extra 1 ft lb difference. The only issue is that I would need additional extensions to get onto the bolt head.
It makes little sense to me to buy a bunch of tools that will be far more limited than a single adjustable tool that covers more range and costs no more than just one of these discrete torque limiting adapters…
I’m trying to learn. So basically there is no sure way to fasten a fastener with an impact wrench, while ensuring you do not overtighten the fastener, unless you have about a foot of clearance over it? This seems really odd to me, so I figured I would ask.
Socket + torque limiting extension + torque wrench = Might need maybe a foot of clearance or more over the fastener.
I mean I know that there are low profile torque wrenches, but maybe a low profile impact ratchet would provide even more clearance, still would need a lot of clearance.
If there were torque limiting extensions that were like an inch or two in length, that would be great! But I don’t think they exist.
It would be costly to be the various torque limiting extensions, and a torque wrench would be far more economical. I’m not sure the time saved would be worth it over just using a ratchet and torque wrench. But maybe for someone who is a professional mechanic the time saved might be worth it.
Same reason this person spent a month searching for a really thin 10mm socket they really didn’t need. Anal Retentive fascination with tools, and probably needs to seek serious help that he thinks (wrongly) that he can get here. Sorry folks I call’em they way I see’em.
These tools do not replace the function of a torque wrench. You are supposed to choose one that is about 20% lower than the final desired torque value and then finish up with a real torque wrench. They could save time in a tire shop that turns thousands of lug nuts in a day but I don’t think they would make your life any better.
They have to have some length in order to allow for controlled twisting that is what limits the torque. A shorter one would have to be thinner and would be less repeatable and would be more prone to being damaged.
Torque sticks are about speed. Used primarily for wheel nuts, or the higher values, axle nuts or pinion nuts. Impact wrenches are primarily for DISassembly, not assembly.
If you want accurate torque, use a torque wrench. If you need extra reach, an extension can be used… but not with universals, crows foot or wobble extension… those affect the readings.
I don’t (but I guess I should) use a torque wrench on wheels, several years at a garage gave me a feel for how tight to go. But if I was so inclined, I’d get an impact wrench plus torque stick for the wheels (more than one stick if my different cars were that different) and use a torque wrench for everything else where precise torque was needed.
I don’t now change wheels enough to warrant it. If I still lived in Anchorage, swapping summer/winter wheels/tires, I’d go the torque stick route.
I use an impact wrench for loosening hardware only. You don’t need (or want IMO) the impact function on tightening. For that I use air ratchets and/or hand tools. For measured torque, where needed, I use a tool designed for the purpose, a digital torque wrench.
But I am not a professional where speed is a huge factor. The torque sticks are designed for repetitive work dedicated to a specific task so it can be performed as fast as possible. The whole purpose would be defeated if you had to keep swapping them in/out to do various tasks.
Thanks for all the help guys. So its it true that torque limiting extensions are good for air impact wrenches only? I have seen a few people claim this online. But no where on any product page for a torque limiting extension, do I find this specified. I see plenty of people on YouTube with an electric impact wrench to put lug nuts back on. I’m trying to clear this up.
Also why the 20 % lower than the specified value? I know that there’s of course a tolerance, but 20 seems extreme. Are these that inaccurate? I’m sure it’s specific to the manufacturer and so forth, but are the examples of ones that are that inaccurate.
I’m thinking of maybe just getting single one for my lug nuts at this point. But I don’t have an air impact wrench, so it might be a mute point?
I already have a decent torque wrench. Just thinking maybe save time with a torque limiting extension. Or be able to lighten lug nuts while my car is still in the air. But I’m seeing conflicting information online that they are for air impacts only. But this seems to come from the concern of older cordless impacts whose ability to apply torque would gradually decrease as the battery drains. It seems most modern day batteries don’t have this issue, were performance dramatically drops off when it gets extremely low on charge that is very noticable and would prompt somebody to switch out batteries.
I get the idea though, if your not applying a constant torque with an impact, or possibly drop below the torque rating of the torque limiting extension, then obviously they won’t work as expected and won’t be accurate. For example a 500 ft lb battery impact is operating on less than 5 percent charged and can only output 200 ft lbs of torque, a 250 ft lb torque limiting extension would provide a false positive of reaching 250 ft lb of torque on the fastener as it is no longer able to rotate the fastener.
I also live in the rust belt and use snow tires in the winter (on one car), and all season tires the rest of the year. I maintain two vehicles. So I do a bit of removing and taking off tires.
The reason is, it’s recommended that a torque wrench be used after using the torque stick to check for proper torque.
Well, if I have to break out the torque wrench anyway, why would I use a torque stick?
I just run down the lug nuts with my battery powered 1/2’ drive impact gun, and once the vehicle is lowered to the ground, I finish torquing the lug nuts with the torque wrench.
