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lug bolts

2K views 21 replies 8 participants last post by  MBGraham 
#1 ·
1998 turbo diesel 300 cannot get lug nuts off, any suggestions
 
#9 ·
exactly. one of the very very few cases where a rattle gun is better than a breaker bar. way to much risk of off axis torque with a breaker bar for this application, especially with the long extention lug bolts.

Hint. start with a blast of areo kroil penetrating lube and low torque setting to get the vibration to break any corrosion "weld" wait 30 minutes or so then try again increasing the torque if needed.
 
#4 ·
you need extra leverage. use a long bar that is hollow, that should do it.
they must have used an air gun to tighten them
 
#5 ·
you need extra leverage. use a long bar that is hollow, that should do it.
they must have used an air gun to tighten them
 
#6 ·
whats going on with the site today
I get warnings that my posts are not posting then they post twice
 
#7 · (Edited)
If he has those extended lug bolts like picture below, some of those methods could very well break the bolt. Search the forum and you will find it HAS happened! Then he is in deep!

I would get a can of Liquid Wrench, PB Blaster or even WD-40 and using long straw, spray it both in the bolt cavity and on back side of wheel where it butts against the brake rotor. Jack car up and rotate wheel so you can spray one bolt at a time, or if just one, get it at top.

Another option is to apply heat to end of bolt with a small butane torch. If it expands and contracts it might come off easier.

If an impact wrench is used, best to use one you can set torque on to a low number - say 70ft-lb, so it won't break the bolt. But that might not get the bolt loose. If not go a bit higher, but not more than say 120ft.lb.

 
#8 ·
I think all broken bolts I have seen posted on forums were broken by bending force, not by torque. If it breaks, it breaks and you drill it out, but my guestimate is that it takes about 400 ft-lb to break those bolts by torque, so plenty to play with.
The video 124lover shows how people apply principals from one design to other and screw themselves.
What works on shallow lug nuts, will not work too well on extended heads bolts.
 
#10 · (Edited)
I would be interested in the "estimate" part of Guestimate! It's been a long long time since I did a course on strength of materials, but I remember enough to know that it is not easy to calculate the torque required to shear off a bolt. I would think it would be safe (but not recommended) to torque our lug bolts to about 110-120ft.lb. They would probably start to yield at about 1/3 more, so say 150ft.lb.

It's taking them out that is the problem. Especially if protruding threads have rusted and cause high friction. What torque is required is anyone's guess. But in many cases (not just on our long bolts) the bolt did shear.

That video is well done, and I have used the same technique. But been very careful to only move the bar just a little to see if the leverage does the trick. But it is not a smart thing to do. Who wants a broken bolt that has to be drilled out!

I have found that patience is a good tool. Let the PB-Blaster do it's job overnight. Using a torque stick to limit torque with impact gun is another option. I have one or two, but they are a bit expensive.
 
#11 ·
I had my share of dealing with wheel lugs, including motorhomes, where reccomended 450 ft-lb on one occasion come well over 2000 ft-lb. To visualize - think 8 foot breaker bar extensions with dual action levels.
So coming back to extended heads, about 10 years ago I had 1 bolt that somehow become stuck. I had to get my commercial breaker bar what I estimate took about 250 ft-lb to remove the bolt. Bolt did not give any signs of breaking and I can "feel metals" with my hand.
 
#12 ·
FWIW, after I bought new tires for the E300, the tire guy bent two of my (long) lug nut when tightening them.

I tried PB, WD, industrial impact gun, lots of prayers (and an imagined ritual sacrifice) before I broke out the sledgehammer. Two hard wacks on the socket bit made it loose enough for my impact gun to screw out. This worked for me.

I was just happy that I didn't have to weld something to the lug nut, or drill it out. All this talk about theoretical torque and break point.....I'm a mechanic, not an engineer, Jim! :p
 
#13 ·
Yes, the impact often does the wonder.
On the mentioned above 2000 ft-lb nut on motorhome, I was at the end of my options.
Had long extension pipe, jacks to support the wrenches level, but the cross bar on factory wrench start to bend.
In last resort attempt I gave 2 lb hammer to my wife and when I was pushing pipe close to bending the bars, wife tapped the big socket with hammer. That tap broke the hold and the nut snap loose to came off with hand turn.
Impact before turning work for Deplore, but kudos for one who can figure out how on W210 smack the socket, while turning at the same time.
 
#17 ·
but kudos for one who can figure out how on W210 smack the socket, while turning at the same time.
:) :) Yes! - they should get kudos if their wife won't help.

Kudos too to anyone who can bend one of those long lug bolts with a socket and breaker bar. Most of the bolt is recessed in the wheel opening and all you have is about 1/2" of head out near the surface of the wheel for the socket to fit onto. And the socket fits quite snug inside the wheel opening.

In this pic, one broke, one not.



Anyone with those long bolts should read this thread and get them changed toute suite! Then get a 1/2" torque wrench and put the new bolts in yourself or make sure your shop has one and has it set at about 85 ft.lb.
 
#19 ·
In my opinion, all this talk about stuck lugs, over-torqing, etc., misses the main cause of stuck lug bolts in these cars. If you unscrew a lug bolt and look at the end of the thread you will see rust. The bolts are plated so the rust comes from the deterioration of the threads in the hubs. If you were able to keep the hub threads from rusting, the lugs would likely not seize.

I know it is controversial, but if you applied a protectant to the hub threads to keep the rust at bay, the rust could not seize the bolts and the hubs would last longer. I don't believe the torque of the bolts would be affected as the torque is generated primarily by the bolt seating against the rim.
 
#22 · (Edited)
Came back from a couple of months down South. One tire of our stored 98 E320 was almost down on rim (other 3 ok).

Decided I would remove wheel and take it to shop to have rim sealed.

Headsup: It was driver front wheel. Used car's jack. Found out that driver side door can only be opened part way before it hits into jack! Didn't do any damage, but could easily dent or scratch door.
The lug nuts would not budge using electric impact gun :( Nor with my breaker bar. Eventually after about 4 hours, using PBblaster, hammer/socket and a propane torch the lugs came out. Ran impact gun both ways. Heat is what worked. (By the way, some time back, I got rid of the long lug bolts that are more prone to breaking)

Didn't want to fight with other wheels, so took car to local shop for tire repair, but asked them to also remove and replace the other three wheels as well. And set them to 80 ft.lbs. I will double check when we get car back. They will also clean up hubs. (Charged me $25 each for leak repair and R&Ring wheels. Plus extra $48 because they also had hard time getting bolts out - used extended breaker bar!)

Good thing for me, was that I had the C230 7 spoke wheels on the car. Makes it a lot easier to get heat and PBBlaster into hub area:
 

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