How much with Air Impact Wrench to tighten lug nuts

[Shinare]

I have a 20g air compressor and I've used a cheapo Kobalt impact wrench to rotate tires and to change brake pads etc. I've always wondered how much "oomph" to put the nuts back on with. I dont want to pull out the lugs, but I also dont want my wheels falling off. I set the wrench on low and tighten until they stop turning, then hit each one twice with 5 or 6 impacts in a star pattern.

Amy i tightening too much, not enough, or sounds about right? Whats a good way to tell?

Thanks!

PS> I set the tool pressure to whats specified in the manual. (I can't remember off the top of my head what that is but I look every time)

[ilikerice]

just get a set of torque extentions

http://www.google.com/products?q=torque+extension+set&hl=en

air impact guns over tighten them so bad and adjusting them to the right pressure just doesnt make me feel comfortable.. i just zip them on with my makita cordless impact and then drop the car and use a real torque wrench to finish the job.. reliable and consistant

[Klink10]

Torque wrench only 76 ft lbs. on stock steelies. That's what my owners manu-el says.

[fnkngrv]

When I went to college for Automotive Tech my Instructor had a motto:

"Air tools are for removal, not for installation on ANYTHING that needs to be torqued"

That is all I am gonna say about that.

[severous01]

torque sticks....but look at the +/- rating on them...sometimes it's upwards of 50%.

but, i use the torque sticks from harbor freight because they have the 1/2" drive on the end for any socket....not a custom size lug adapter like most sticks.

but as stated...impacts are good for loosening, and running (nuts and bolts to the stop) and that's about it. although, with as many wheels as i'm taking off and putting on all day, the sticks are the easiest thing to use...at least i'm not running them with full force of the impact.

[Shinare]

Thanks for the replies guys. One of these days I'm going to have to invest in a torque wrench of some kind. Maybe Santa will bring me one. :)

[markitect]

I've had good luck with a $30 dollar click torque wrench. I checked it against someone's craftsman with the gauge on it, and it is within 5%.

[MUSKOKA800]

When I went to college for Automotive Tech my Instructor had a motto:

"Air tools are for removal, not for installation on ANYTHING that needs to be torqued"

That is all I am gonna say about that.

I firmly agree. Now who's going to tell the grease monkeys at all those tire shops???

[Shroomster]

I firmly agree. Now who's going to tell the grease monkeys at all those tire shops???

who's going to tell them? how about you tell them that....seeing as they're getting paid (most likely) LESS than the 16 year old working a grease fryer at mcdonalds down the street. most of the lube/tire guys at the shops people are talking about are either at the end of their work career or are just starting out. They don't give a rat's ass about the car. If you're flagging hours or on hourly but still under the gun for a quota, and not on salary, then you really think you're going to take the time to pull out a torque stick or wrench drop the car to the floor and check all four wheels? hell no, get the car out quick as you can. When oil changes and tire rotations bring in more than ".3" then there might be a little change. the only reason it is done at tire shops is because it's a specialty shop. Discount tire, for example on a good day has 2-5 people per vehicle.

if you're making 8-10/hour and have a rent or mortgage and other expenses, a q.c. tool is one of the last things you think about buying.

you can buy a cheap set if you want, but I prefer to use quality tools, I know that you can get reliability out of knock offs and no names but seriously, there's a reason most of the tool trucks are still on rotation in cities.

/rant

[severous01]

I firmly agree. Now who's going to tell the grease monkeys at all those tire shops???

if you got paid 3 tenths of an hour to change a tire, you'd definitely start using a gun. you're already losing money on 3 tenths....because it generally takes longer with the more common lower profile tires....so, you're losing to begin with and now you're taking more time....not profitable.

as long as you're not 'hammering' them and keeping on the trigger you should be fine. run all the lugs, tap the trigger a time or two and be done with it. you could also turn down the power on some of the higher end. experiment and see how much torque setting 2 vs setting 3 makes vs full power. get into the range and start being smart with your air tools. if you dont have a level switch on it you can always get a pressure regulator.

i'm a mechanic for BMW. i have a small chest about 4 feet wide and 2 feet deep, and about 3 foot tall. its loaded with tools in just about every drawer. any way, i've got about 20k in tools. and i dont have enough. my impact gun alone was almost 500 bux. i agree that you can get stuff done with craftsman and harbor freight....i even use their stuff my self. but higher quality tools make for easier jobs. they dont round, they dont break, they dont split, and there's no question that if something does happen that it'll be replaced no questions asked. that's why i buy snapon and matco.

[ilikerice]

i agree with the last two comments 100%.. i used to work for lexus for 4 years and i got my snapon toolbox and matco roll around filled with snapon/matco tools. they disign those tool to fit comfortable in your hand for real mechanics who do the job everyday/all day. now for the guys who work on thier cars maybe every other weekend or each weekend at the most, i have nothing against harbor frieght but if i was too buy a tool just use it once a month, id pick a craftsman. the warranty is awesome, as long as it still says craftsman on the tool u can trade it out anytime.

found a craftsman flathead that had the tip broken off. still said craftsman on the handle. took it to sears and said my tip broke and pooof.. they swaped it out for a brand new one..
not saying snapon wont do the same but holding a snapon screwdriver compared to a craftsman feels like extacy, lol.

my 2 cents

[advocate]

76 foot pounds

if you don't trust what the safest car maker in the world recommends then not sure what to say

this is somewhat hypocritical as I don't own a torque wrench. But I tighten my own lugs by hand and check them weekly.

[MUSKOKA800]

I didn't mean to ruffle any feathers.
Normally I do our change-overs myself in the driveway. But if I'm buying new rubber I simply tell the sales rep. to take my lugs to 75 lb/ft. Then I watch his guy at work. If the guy isn't professional and takes obvious shortcuts I simply take my future business elsewhere.

[severous01]

well, he's gonna use either a torque stick or a gun unles you specifically ask him to use a wrench. just sayin.

and you didnt ruffle feathers lol....just got a lot of different opinions. but i can tell you this as well....i've never had a wheel fall off a car i've put the lugs on.

[2005rs]

how does a torque stick work? it just looks like an extension to me. not that I'd use one after reading the above posts ; )

[Uber_Otter]

You can get a cheap 1/2 torque wrench from Harbor Frieght for 20 bucks. Perfect for lugs but I would calibrate it for any precise work "heads, bearings"
I ussually don't use a torque wrench myself. I use my 1/2 inch ratchet with a 5lb baby sledge. I tap it tight with a 1 foot back swing of the hammer. No more, no less. I have never had wheels fall off or broken a lug.

You will have to calibrate your arm\swing against a torqued bolt :) consistency and common sense.

[Uber_Otter]

how does a torque stick work? it just looks like an extension to me. not that I'd use one after reading the above posts ; )

Once the correct torque has been reached; The shaft will flex in sync with the blows of the impact gun and bleed off torque.