I have a 95 Bronco and it seems everytime i turn around i find that one or more of the lugnuts loose. I put them on there with my impact gun and they get tight on the stud. ( I do the same to other vehicles with the same impact and those dont seem to habe a problem) I will also screw the nuts on there with my hand and then use a breaker bar to get them tight but like always they will become loose. For a few of the nuts that dont back off they seem to tight. And when i go to take the tires off the truck to work on it; when i try to back the nut off the stud it breaks the stud off. Now i have tried different lugnuts and different studs but this seems to be a re-occuring problem. The holes cut in my rim for the studs are perfectly round and the tires dont seem to wobble on the studs when i tighten them all down. I have had this problem for a while now and it just seems to be getting worse. I cant think of a solution for this other that replacing all the nust and studs but that has been done many times...?
Any and all help is greatly appreciated. Im only running 31" tires do they dont put to much stress on there but then again who knows.
Thanks
Gary

95 Bronco 351W 6" Jack Stand Lift

 

It's important that you have the right face on the lug nut to match your wheels. Do you have aftermarket wheels?

I use a good 'click' torque wrench to get my lug nuts right - thay're all supposed to be about 100 ft-lbs. I think. But with that torque wrnech or a breaker bar of any good length - like you use - this really doesn't take a whole lot of pressure to tighten them up to spec.

Are you gradually building the pressure up on each of the five lugs in a cross-star pattern?

 

re: breaking studs

Stop using an impact wrench and breaker bar and start using a torque wrench.

Most likely cause ... you torque them down way over spec., this pulls the stud towards the lug nut more than it should and stretches it beyond spec. While you are doing this the stud is stripping the lug nut and twisting clockwise.

When you take it off, the lug nut is basically stuck because of the stripped threads and the stud acts just like a coat hanger that you have bent back and forth many times (because you have ridden on the truck and produced thousands of twisting motions while it is beyond its limit of where it can flex back to normal length when pressure is released).

The stud is now weaker than the cross threaded lug nut (when it is suppose to be stronger) and it snaps.

If you look at the lug nut from a snapped stud the threads will probably look squished and thin compared to a good/new lugnut.

Some Fords (forget what you said yours was) need so called hub "centric" wheels where the rim exactly fits the hubs F&R so the rim centers correctly when tighten down.

Which on some vehicles (ex.Explorers with drums) makes getting them off nearly impossible if they are rusted.

 

[updated:LAST EDITED ON 26-Aug-02 AT 10:58 AM (EST)]This is a common problem with alloy wheels. You have to torque them down to specs and then retorque after 100 miles and then every 500 miles or so. Steel rims do not have this problem but the alloy's do.

 

Wow thanks for the fast responses, i really do appreciate it. My wheels are aftermarket, they are the Rockcrawler steel chrome modular rims or something like that. Dont quite know the full name of them but is close to that. I do use the star-pattern to put the nuts on there. And i was unaware that puttin to much pressure on the lug nuts would stress the stud, but it makes perfect sense to me now. Ill look in to getting a torque wrench, the only problem is they are quite pricy, but if itll solve my problem than its worth it. I just figured that the ol impact could be used to put them on but i guess every auto shop uses a torque wrench to ensure lug nuts on there or what?-no biggie. And i have never heard of these "centric" wheels. Sounds interesting, and ill definatly have to ask around bout those. Just one more thing, does it sound wierd to yall at all that im breaking so many studs and having thse problems so often or is this just common with my method of putting hte lug nuts on there? Im getting really good at taking my front and rear ends apart each week.
Thanks again for the help yall.
Gary

 

Well, yes, the reputable shops I know of do use torque-limiting extensions on their air guns. At our garage we have a set of four (I think from Mac tools) of varying thicknesses that essentially stop the nuts from tightening further than a specified toque (give or take a little) via harmonic vibration. We use a supplied chart to tell us which extension to use on which vehicle.

But I agree that a lot of shops don't use them, either. Though through the years people generally learn when to stop applying the air gun - most mechanics do not apply it (in the star pattern) until the lug completely stops turning.

Again, I'm wondering if your lug nuts are the stock OEM type, and the wheels need more of a face, or thicker lug nut. I've seen a Mustang come in with aftermarket wheels that still could have used the 'acorn' type face lug nuts, but it certainly needed some other size of lug nut than the factory ones. I had no clue where to get the 'proper' lug nuts locally, so I made the girl sign a waiver before letting her drive it away.

If your wheels holes are any larger than stock, you'll probably need lug nuts with more of a face on them. (I think that's what that girl's mustang's problem was)

I have a '93 F-150 and I don't believe my wheels are centric, so I wouldn't think yours would be. But I'll have to look next time I take 'em off.

Yes, it does sound weird that you're breaking so many - but we have no way of knowing your experience level with an air gun or breaker bar. Heck, you could be some 16 year old kid with his first vehicle for all we know.

Best of luck with that!

 

Haha yea thanks, I wish I was 16 and on my first vehicle, that away messin up so many times would be expected. But as you said at the end too, i dont have to much experiance with air tools, only about a year or two but ive been using breaker-bars for a while now. Only had this truck for about 2 years now so i dont know the history behind it but once i got it, the first thing i did to it was get the new wheels. And im using those chrome lugnuts, thinkin about changin to the open nut kind so they might fit on there better and tighter...

Gary