*%&^ing Castle Nuts!!!!!!!!!!
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
*%&^ing Castle Nuts!!!!!!!!!!
I'm trying to install my trailing arms with the correct bolts now. I pack the shims tightly in the pocket, on both sides of the bushings. I then try to torque the damn castle nut to 50 ft/lbs and the damn nut strips. I've used two different torque wrenches, both of which are brand new and calibrated. I am so pissed right now, I'm about ready to just go ahead and use a grade 8 bolt and nut, and then when the alignment is done, take the nut off, cover the threads in red loctite and be done with it. Fu*king cheap quality nuts...I just don't understand anymore. If I am capable of rebuilding my entire rear suspension, then I am capable of torqueing a nut...should I just go with the grade 8 bolt and nut, then use red loctite before and after the alignment?
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
I'm trying to install my trailing arms with the correct bolts now. I pack the shims tightly in the pocket, on both sides of the bushings. I then try to torque the damn castle nut to 50 ft/lbs and the damn nut strips. I've used two different torque wrenches, both of which are brand new and calibrated. I am so pissed right now, I'm about ready to just go ahead and use a grade 8 bolt and nut, and then when the alignment is done, take the nut off, cover the threads in red loctite and be done with it. Fu*king cheap quality nuts...I just don't understand anymore. If I am capable of rebuilding my entire rear suspension, then I am capable of torqueing a nut...should I just go with the grade 8 bolt and nut, then use red loctite before and after the alignment?
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
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From: South of giving a damn
St. Jude Donor '11, '17
Team Owner
Joined: Jul 2004
Posts: 40,408
Likes: 792
From: Redondo Beach, California
Why does the trailing arm castle nut need to be torqued at 50 ft-lbs, or indeed at any significant torque? The trailing arm bolt works in shear, not tension. In other words, the trailing arm bolt really works like a pin and not, per se, a bolt. All you really need to worry about is that the "bolt" does not work its way out of the frame attaching holes.
Last edited by 68/70Vette; Mar 20, 2008 at 10:45 AM.
Drifting
Joined: Sep 2007
Posts: 1,572
Likes: 51
From: Wichita Kansas
Where did you get the torque spec? That does sounds high. What are the nuts made of that you are torquing? I know that you could go with stainless casttelated.
On casttelated nuts you would mostly find a torque spread and not just a set torque. With a torque spred you can torque to the min; then set the wrench to the max and align the cotter pin hole before the high break. You may have alread known this.
I would look in another sourse for the TQ as I realy think 50 ft/lbs is way too tight.
On casttelated nuts you would mostly find a torque spread and not just a set torque. With a torque spred you can torque to the min; then set the wrench to the max and align the cotter pin hole before the high break. You may have alread known this.
I would look in another sourse for the TQ as I realy think 50 ft/lbs is way too tight.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
I was able to find two original castle nuts from my parts bin in the garage last night. I torqued them down with a regular bolt and it held great. The reason for the high torque rating is to pull the whole assembly together so the bushing is clamped between the shims on either side of it. You don't want that thing moving on you. I think the issue was caused more by the way I made the bolt. I bought a grade 8 5'' long bolt, and used a die to put more threads on it. This creates a step on one of the threads - it doesn't have as much bite as the other ones. I am referring to the one thread that extends beyond the original threads. Its hard to explain, I'll post a picture tonight. So here is what I have planned for tonight. I am going to go and buy myself 6" long grade 8 bolt (way longer than needed), and cut it to length. This will leave me with a bolt head and just a plain shank. Then I can use my 7/16-20 die to put the threads on it - all threads will have the same amount of bite. I'll use the two castle nuts that I found in my parts bin and see if that works. This coupled with the stronger oem castle nuts should work.
Team Owner
Joined: Jul 2004
Posts: 40,408
Likes: 792
From: Redondo Beach, California
I've installed trailing arm bolts, and I have a set right now setting in a spare frame. Maybe I'm missing something from your description above. I'm not at home now, but as I recall it, the bolt head/washer contacts the outside of the frame. The castle nut/washer contacts the outside of the frame on the other side of the pocket. It seem to me that no matter how much you tighten the castle nut, it doesn't put any pressure on the shims at all. Tightening the nut, just squeeses the outside of the boxlike frame, and unless you tighten so much that you deflect the frame surfaces, the shims and trailing arm itself don't "see" the tightening force at all. ?? Like I said, maybe I'm missing something.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
I've installed trailing arm bolts, and I have a set right now setting in a spare frame. Maybe I'm missing something from your description above. I'm not at home now, but as I recall it, the bolt head/washer contacts the outside of the frame. The castle nut/washer contacts the outside of the frame on the other side of the pocket. It seem to me that no matter how much you tighten the castle nut, it doesn't put any pressure on the shims at all. Tightening the nut, just squeeses the outside of the boxlike frame, and unless you tighten so much that you deflect the frame surfaces, the shims and trailing arm itself don't "see" the tightening force at all. ?? Like I said, maybe I'm missing something.
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Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
Where did you get the torque spec? That does sounds high. What are the nuts made of that you are torquing? I know that you could go with stainless casttelated.
On casttelated nuts you would mostly find a torque spread and not just a set torque. With a torque spred you can torque to the min; then set the wrench to the max and align the cotter pin hole before the high break. You may have alread known this.
I would look in another sourse for the TQ as I realy think 50 ft/lbs is way too tight.
On casttelated nuts you would mostly find a torque spread and not just a set torque. With a torque spred you can torque to the min; then set the wrench to the max and align the cotter pin hole before the high break. You may have alread known this.
I would look in another sourse for the TQ as I realy think 50 ft/lbs is way too tight.
Melting Slicks
Joined: Apr 2004
Posts: 2,008
Likes: 38
From: Space Coast Gator Territory
You may be getting too hung up on the torque number and not seeing the big picture. There are going to be different ideas on this assembly and this is mine. After stacking shims to my satisfaction, I make them fit tightly inside the pocket, I will put the thickest shim in last. It will fit so tight, I need to drive it in with a hammer, but not so tight it spreads the frame pocket. If you don't shim it that tight, you will be closing the pocket when you tighten the bolt. You want it to be 'neutral' as far as that is concerned.
You can use a grade 8 bolt, but the correct bolt had a rounded and narrowed tip to guide it through the shims. This isn't absolutely necessary, but it is there for a reason and correct if you are going NCRS. It also has a correctly located hole for the cotter pin. You can drill your own hole, so a grade 8 bolt will work fine. If the T/A is shimmed as I describe, just make the nut tight with a box wrench and back it off as necessary for the cotter pin hole. If when you tighten the nut the frame pocket is drawn together, you did not install the shim pack correctly. There is no reason the bolt threads should strip in the process.
You can use a grade 8 bolt, but the correct bolt had a rounded and narrowed tip to guide it through the shims. This isn't absolutely necessary, but it is there for a reason and correct if you are going NCRS. It also has a correctly located hole for the cotter pin. You can drill your own hole, so a grade 8 bolt will work fine. If the T/A is shimmed as I describe, just make the nut tight with a box wrench and back it off as necessary for the cotter pin hole. If when you tighten the nut the frame pocket is drawn together, you did not install the shim pack correctly. There is no reason the bolt threads should strip in the process.
Burning Brakes
Joined: Feb 2006
Posts: 1,024
Likes: 1
From: AL
plus remember the nut is supposed to strip first. also you may already know that rolled threads are stronger than cut threads, although, the load on that bolt is not tension as already mentioned (minor diameter still different).also use the slotted shims vs the shims with holes - then you will need only to loosen the nut for adjustments, shim changes, later on . . .
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
You may be getting too hung up on the torque number and not seeing the big picture. There are going to be different ideas on this assembly and this is mine. After stacking shims to my satisfaction, I make them fit tightly inside the pocket, I will put the thickest shim in last. It will fit so tight, I need to drive it in with a hammer, but not so tight it spreads the frame pocket. If you don't shim it that tight, you will be closing the pocket when you tighten the bolt. You want it to be 'neutral' as far as that is concerned.
You can use a grade 8 bolt, but the correct bolt had a rounded and narrowed tip to guide it through the shims. This isn't absolutely necessary, but it is there for a reason and correct if you are going NCRS. It also has a correctly located hole for the cotter pin. You can drill your own hole, so a grade 8 bolt will work fine. If the T/A is shimmed as I describe, just make the nut tight with a box wrench and back it off as necessary for the cotter pin hole. If when you tighten the nut the frame pocket is drawn together, you did not install the shim pack correctly. There is no reason the bolt threads should strip in the process.
You can use a grade 8 bolt, but the correct bolt had a rounded and narrowed tip to guide it through the shims. This isn't absolutely necessary, but it is there for a reason and correct if you are going NCRS. It also has a correctly located hole for the cotter pin. You can drill your own hole, so a grade 8 bolt will work fine. If the T/A is shimmed as I describe, just make the nut tight with a box wrench and back it off as necessary for the cotter pin hole. If when you tighten the nut the frame pocket is drawn together, you did not install the shim pack correctly. There is no reason the bolt threads should strip in the process.
Sounds good. I will make myself the bolt, pack the shims tightly, and then make the bolt/nut snug. The shims were already tight in the pocket, but I can make them tighter probably. I will go home tonight and follow this procedure
Melting Slicks
Joined: Apr 2004
Posts: 2,008
Likes: 38
From: Space Coast Gator Territory
Equally stacked shims on both sides of the T/A usually get toe-in in the ball park. You should check this and get both R&L sides the same. This is easy if you have a laser level. You want to shoot a beam down the frame and measure out from the frame rail. Making a place to locate the level on the T/A is usually a PITA. If you have a spare rotor you can mount it over your T/A rotor with the spare rotor facing out and the mounting flange over the wheel studs. This will provide a level surface to mount your laser level. If the beam is the same distance along the rail it is set at zero. This is a PITA if you need to move shims around, but now is the time to get it right. After it is on wheels you can play with the camber.
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
It seem to me that no matter how much you tighten the castle nut, it doesn't put any pressure on the shims at all. Tightening the nut, just squeeses the outside of the boxlike frame, and unless you tighten so much that you deflect the frame surfaces, the shims and trailing arm itself don't "see" the tightening force at all. ?? Like I said, maybe I'm missing something.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
This is exactly what I thought. If you put a trailing arm in the pocket with tightly packed shims, it is stiff. Once you tighten the bolt, it becomes extremely stiff. I'll probably use your method to tighten the nut as much I can using my wrench (won't be 50 ft. lbs, but it will be nice and snug).
Advanced
Joined: Feb 2008
Posts: 88
Likes: 0
From: PORT ST LUCIE FLORIDA
I Had The Same Problem Stripping The Castle Nuts, I Had Bought New Bolts, Figuring New Bolts For New Suspension I Used The Old Nuts Torque To 30 To 35 Ft Lbs No Problems Lined Up The Cotter Pin
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
a message from dan at vansteel...
"Stack your shims in really tight once you figure out what toe is and tighten the nut. After the lock washer is compressed, go a little further or until you get a cotter pin in. Are you using flat washers at the head of the bolt and at the end of the bolt as well? If not you need to and they need to be 7/16" SEA #8 Thick. Don't go by the torque spec in my book. It's wrong and shouldn't be in there"
Drifting
Joined: Sep 2007
Posts: 1,572
Likes: 51
From: Wichita Kansas
From reading all of your project I knew that you knew what you are doing
. I just think that TQ is just a little too high. Later in this thread a TQ of 30-35 is mentioned and that is what I was thinking just didn't have anthing to back it up and still dont. There are puplications that give general TQ's on all fasteners base on the metal, hardness and size. You could look that up for the stock bolts and I would think a chart will give you a much lower TQ.
Pro
Joined: Mar 2005
Posts: 683
Likes: 4
I got my bolts and other parts from Vette Brakes and Products. If you go to their website they have a listing for torque settings. 50ftlbs is correct. I would give them a call as they were very helpful when I did all my suspension. Here's the link
http://www.vbandp.com/instructions/h...specsR0102.htm
Good Luck
Steve
http://www.vbandp.com/instructions/h...specsR0102.htm
Good Luck
Steve
Last edited by Steve COSD; Mar 21, 2008 at 01:01 AM.