Danger will robinson, danger....

[Volvos rock]

Sorry you'll have to excuse me I just got off night shift and I'm a little punchy...so on to my question, on my 02 V70XC.

Twice[cussing] in the last two hundred miles or so one of my front wheels (drivers side) has worked loose. The lugbolts get loose enough that the wheel is loose:eek:. This is after being properly tourqed. I had to stop on the way home this morning and tighten them. Anyone have any insight, the lugbolts look pretty bad as far as rust is concerned and Ill be replacing them on that wheel this afternoon. Any ideas? I can not see any damage to the wheel thankfully.

[Ars Gladius]

Thread damage on the bolts. Thread damage on the hub flange. Damaged bolts (over stretched).


This is after being properly torqued...

All three can be from over torquing. You said that you have properly torqued them, but has everyone who has touched the wheel done the same? Mere seconds of over use (or use at all) of an impact gun to tighten, can FUBAR bolts / threads. While most torque values are also measured "wet", but the wheel lugs must be done "dry". [Edit, due to error.]


The lug bolts look pretty bad as far as rust is concerned...

First two can also be from corrosion damage. (Which can also affect correct torque.)

[haoz129]

Torque values are also measured "wet". If you put a dry bolt in, you will hit the spec'd torque value before the bolts has been stretched correctly, and thus will not clamp as designed and may loosen.


Sorry, Ars.

I believe lugs for XC70 need be torqued when dry.
In my 2003 xc70 manual mentioned:"Correct tightening torque on wheel bolts must be observed. The wheel bolts should never be greased or lubricated. The extended, chromed wheel bolts must not be used with steel rims, as they make it impossible to fit the hub caps."

So it will be over torqued if we measure when wet.

I do know on some trucks wheel lugs need be lubed. But XC70 is not.

Thanks.

[Ars Gladius]

I believe lugs for XC70 need be torqued when dry.

You are quite right. :o

[Astro14]

I have never had a wheel bolt loosen on this car, and yes, I check after 100 miles or so (aviator paranoia on machinery...). I torque to 100 ftlbs with a good wrench.

I would pull the wheel, wire brush the mounting surface on the hub, clean the mounting surface of the wheel, then inspect the wheel bolts - replace any questionable ones, then look at the threads in the hubs - make sure they're not damaged...you may need to run a tap through to clean the threads, finally, look at the conical seats in the wheels themselves, they should be relatively clean and smooth. If they've got excessive galling, that could easily throw off the torque.

I'm with the guys who suspect the use of an air impact, it's very easy to cross thread the wheel bolts with one (ask me how I know...).

Wheel bolts are done clean and dry. Torque is an approximation of the desired bolt stretch to achieve the design clamping pressure. Damaged threads reduce the clamping pressure for a given torque since the torque goes into overcoming and that = loosening due to the differential expansion of aluminum wheels and steel bolts. Poor seating of the wheel on the hub will have the same effect.

[Volvos rock]

Ill be delving further when my wife returns (baby duty currently[thumbup]). Will report with my findings. Dealer only had 3 lugbolts of the new kind (chrome with collar, but he came down from $10.50 a piece to $6, I ordered the rest from IPD at $5.15 a piece with shipping).

[Volvos rock]

Yes Astro, I have never had this either....Alright, no more play in the hub flange on this wheel as compared to any other, with new or old bolts. I did find that the rotor retaining screw was loose. New rotors about 1k ago, so I applied blue loctite and reinstalled (thought I did this when I installed originally). Wheel looks fine, including mating surface for bolts. All else looks good. Reinstalled wheel w/ 3 new lug bolts (replaced the 3 that looked the worse) and tourqued with wheel up, lowered car and checked tourque again (got a little more out of it). we'll see...[sly]

[Volvos rock]

Yes Astro, I have never had this either....Alright, no more play in the hub flange on this wheel as compared to any other, with new or old bolts. I did find that the rotor retaining screw was loose. New rotors about 1k ago, so I applied blue loctite and reinstalled (thought I did this when I installed originally). Wheel looks fine, including mating surface for bolts. All else looks good. Reinstalled wheel w/ 3 new lug bolts (replaced the 3 that looked the worse) and tourqued with wheel up, lowered car and checked tourque again (got a little more out of it). we'll see...[sly] No air impact since well before the brakes/rotors.

[USHGAPB]

Twice in the last two hundred miles or so one of my front wheels (drivers side) has worked loose. The lugbolts get loose enough that the wheel is loose. This is after being properly tourqed. I had to stop on the way home this morning and tighten them.

This reminds me of my then-girlfriend's car that developed some "wallowing" handling characteristics. After checking the front-end parts, I noticed that the mounting holes on the steel wheels were slightly egg-shaped from being driven with loosened lug-nuts on both front wheels. She attributed this to a former boyfriend, but that's another story.

We were advised by a local repair shop the lug-nuts could never be properly torqued, and had to replace both front wheels.

Just some food for thought. If the problem continues, maybe try checking the fit of a known good lug-bolt in the mounting hole when the wheel is off? If you have a measuring caliper, check the inside diameter of each bolt hole in a cross pattern.

[Volvos rock]

For anyone who may be interested..Installed the rest of the new lugbolts about 200 miles ago, no more issues, checked them yestarday and all was tight like it should be[thumbup]

[Astro14]

Good news...[thumbup]