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Midnight Specialist
02-14-2021, 10:28 AM
Hey all. My car is currently in the shop for a water pump and a few other items, but after doing some research on the TABs, I asked for the shop to test out the TABs how DMC recommends. I ordered some inconel ones and all the hardware for the bushings too just in case they were bad. However, upon thinking about it and the need to keep testing these bolts on the regular, would it be more prudent to just have them put the bolts in while they are under there now or, if the OEM bolts are good, just keep them in? Thoughts?

Michael
02-14-2021, 11:06 AM
Hey all. My car is currently in the shop for a water pump and a few other items, but after doing some research on the TABs, I asked for the shop to test out the TABs how DMC recommends. I ordered some inconel ones and all the hardware for the bushings too just in case they were bad. However, upon thinking about it and the need to keep testing these bolts on the regular, would it be more prudent to just have them put the bolts in while they are under there now or, if the OEM bolts are good, just keep them in? Thoughts?

I have never replaced mine but I have read that if you have an auto, the job is more of a PITA than a manual because of the mount location. Also might be a good idea to have a few extra shims on standby when you do replace them.

Midnight Specialist
02-14-2021, 11:31 AM
It's a manual. I have all new shims and hardware, but my concern would be if I open a can of worms while under there. I think my main concern is this info from DMCH. "CAUTION: The bushings are held to the frame with two 8mm (13mm head) bolts that are threaded into nuts that are welded to the frame. In most cars there is a second nut on the inside of the frame on the bolt toward the rear of the car that locks the bolt to the welded nut. This nut is not shown on any of the parts diagrams. This second nut MUST be loosened (and held while removing the bolt) before attempting to remove the bolts, or the bolt head will shear off. If this happens, access for replacement involves lifting the body off the frame for access." http://support.delorean.com/kb/a72/trailing-arm-bolts.aspx

Michael
02-14-2021, 12:01 PM
It's a manual. I have all new shims and hardware, but my concern would be if I open a can of worms while under there. I think my main concern is this info from DMCH. "CAUTION: The bushings are held to the frame with two 8mm (13mm head) bolts that are threaded into nuts that are welded to the frame. In most cars there is a second nut on the inside of the frame on the bolt toward the rear of the car that locks the bolt to the welded nut. This nut is not shown on any of the parts diagrams. This second nut MUST be loosened (and held while removing the bolt) before attempting to remove the bolts, or the bolt head will shear off. If this happens, access for replacement involves lifting the body off the frame for access." http://support.delorean.com/kb/a72/trailing-arm-bolts.aspx

Youch! I can see why that would be intimidating to do. Here is a vid from EDR5150 that may help.




https://www.youtube.com/watch?v=EXeFsON1q_M

David T
02-14-2021, 03:41 PM
Generally you don't need to replace the bushings unless the TAB's were overtorqued and the metal sleeve inside the bushings got crushed. Replace the TAB's if they are bent or are loose. To determine of a TAB is bent, loosen the TAB and then rotate it by the head. If you see the trailing arm move up and down, the TAB is bent. Before loosening the TAB count the number and thickness of the shims so you can put them back. Write the #'s right on the frame next to the TAB. Torque the TAB to spec and put a dab of paint on the nut and bolt so you can see at a glance if it loosens up. During a proper 4 wheel alignment the castor and camber is checked, the front toe adjusted, the front wheels centered with the steering wheel and the rear thrust angle is set using the shims on the TAB's (if necessary). TAB's are too often neglected because to inspect them you have to remove the shields and that is a PITA because you wind up breaking the 3 studs that hold each shield in place. The original TAB's seem to be OK if they are not bent or were not overtorqued or were found to be loose. If they are found loose, it means they got stretched (overtorqued) and are no longer any good. Because they are such a critical piece of suspension hardware NEVER substitute ordinary hardware in their place.Get them from your favorite Delorean vendor. If you can't torque the TAB properly it usually is because the steel sleeve inside the bushing got crushed. No way to fix that except to replace the bushing. Yes, you must be alert to the fact that there could be locknuts on the small bolts holding the bushings to the frame. The frame is threaded and the nuts are not holding the bushings in, they are locking the bolts. If you try to remove the bolts without undoing the locknuts you wind up breaking the bolts.

Midnight Specialist
02-14-2021, 05:40 PM
Thanks, David. I'm thinking that the best course of action would be to just have the shop replace the TABs and leave the existing hardware in place.

Jonathan
02-14-2021, 07:22 PM
Greetings. Been on DMC hiatus since the Fall as I had been getting sick of car stuff and started working on pinball machines instead. Well, it's full on winter here and I'm sick of the pinball stuff and Jonesing to get my car out... so thought I'd comment here on your thread about replacing TABs.

Michael is right about the job being harder on an automatic. I have an automatic, but you don't, so you might be able to make the decision to replace your TABs easier than I can.

That being said, I wanted to comment about your mention of the second nut on the backside of the bracket. What DMCH wrote is not to make it sound like removing the nut is terribly difficult. What it is meant to tell you is to not FORGET the nut is there, or the results will be terrible. Removing that nut isn't going to be any more difficult than removing any other 40 year old rusted fastener on the bottom of the car (yuck!). But forgetting to take it off first and then trying to loosen the bolt that it's on will indeed lead to the bolt breaking and the piece being still stuck in the welded on nut that's part of the frame.

Here's a little picture I made for you. You mentioned how nice it would be to have all new fasteners and hardware....hmmmm, great idea! And all of these have been sitting in a box for a while because I have been inclined not to f%$k with the TABs on my own car. And mine are not pretty, but they are functional. And after 14 years with the car now, I've learned that some things are better left alone unless you have to do them. The proverbial can of worms on these cars can be horrific and definitely having you wish you had just left it alone.

65605

Ok, see the bushing set-up in the foreground? Now, normally that small bolt you see would go through the assembly like it is, but the first nut it threads into is the one welded to the frame. Then the secondary nut is locked on behind it. I took a second free nut and put them both on the same bolt to try and give you an idea what it looks like. Actually, on a pinball machine leg leveller, they'd call that a jam nut :)

Anyway, that's what you're working with. If the mechanic already goes through the trouble of removing things to access the TABs, you might as well go ahead and replace them. I know if I got it all out, everything new would be going back in. On an automatic anyway, that's not a job you do twice just for the heck of it.

Oh, here's a picture of my TABs on the car from last summer. Aren't they pretty???!!!

65604

CFI
02-15-2021, 04:38 PM
I know if I got it all out, everything new would be going back in. On an automatic anyway, that's not a job you do twice just for the heck of it.

Oh, here's a picture of my TABs on the car from last summer. Aren't they pretty???!!!

65604

My TABS look very similar, and like you I am not about to touch them. I have every nut, bolt, and bushing set aside for my mechanic to do next month.

Helirich
02-15-2021, 08:23 PM
I am looking at do my tabs also. I'm not sure if I understand what you guys are saying. If I want to change them and nothing else, do I have to remove the bolts that hold the bushings? Or are you guys saying if your changing the tabs, you might as well install new bushings. (Necessitating the jam nut removable.)

David T
02-15-2021, 09:04 PM
You do not have to replace the bushings if they are in good shape and you can remove the TAB's without disturbing the bushings.

Helirich
02-16-2021, 10:52 AM
You do not have to replace the bushings if they are in good shape and you can remove the TAB's without disturbing the bushings.

Thankyou

Helirich
02-16-2021, 01:21 PM
Has anybody replaced the tabs with 1/2"? Slightly stronger, more available, but not sure if it will fit in the holes. (Maybe could ream them out)

David T
02-16-2021, 01:32 PM
They won't fit through the sleeves in the bushings and if you try to modify or force them through you will destroy the bushings. Over in Lotus, some owners have been trying to use Heim joints in place of the TAB's. The motion is not a pure up-and-down motion in a single plane. The compliance of the rubber allows for the slight movement in an arc. The rubber also provides some isolation from the road, preventing some of the road vibrations from reaching the frame. This was a very engineered joint and unless you know what you are doing, you should not attempt to modify it. If you have any doubts about the integrity of your TAB's, you should order new ones from your favorite Delorean vendor. Ordinary hardware is not strong enough for this joint.

Nicholas R
02-16-2021, 01:36 PM
Has anybody replaced the tabs with 1/2"? Slightly stronger, more available, but not sure if it will fit in the holes. (Maybe could ream them out)

I have not, but I know of at least a couple owners that have. The sleeve is very tight so you have to run a 1/2" drill through your trailing arms. Once you do it, there's no going back without replacing your trailing arms.

I disagree about 1/2" being more available. A pair of 1/2" grade 9 bolts is no more and no less available than a pair of class 12.9 M12 bolt. Neither are going to be available at an ACE Hardware, but a few clicks at Fastenal, Bolt depot, or McMasterCarr, and either will be at your door step for $5-$10.

Helirich
02-16-2021, 01:58 PM
I have not, but I know of at least a couple owners that have. The sleeve is very tight so you have to run a 1/2" drill through your trailing arms. Once you do it, there's no going back without replacing your trailing arms.

I disagree about 1/2" being more available. A pair of 1/2" grade 9 bolts is no more and no less available than a pair of class 12.9 M12 bolt. Neither are going to be available at an ACE Hardware, but a few clicks at Fastenal, Bolt depot, or McMasterCarr, and either will be at your door step for $5-$10.

I suppose anything is available online, but my local Fastenal has 1/2" instock. (Not M12)

On another note, what is the grade of the stock tabs? I notice two of the Delorean venders offer the bolts, but don't say what grade. I suppose the original bolts were of poor quality, but I wouldn't want any less than grade 8 in there. Would be kind of nice to have "double shear" in that location.

Josh
02-16-2021, 02:21 PM
I suppose anything is available online, but my local Fastenal has 1/2" instock. (Not M12)

On another note, what is the grade of the stock tabs? I notice two of the Delorean venders offer the bolts, but don't say what grade. I suppose the original bolts were of poor quality, but I wouldn't want any less than grade 8 in there. Would be kind of nice to have "double shear" in that location.

Refer back to Nicks post for grading. Stock TABs are class 8.8. Metric is designated by classes, not grades.
I also think it is not worth the effort trying to force a 1/2" bolt in there. Perhaps its the American way though.

I do agree they should be double sheer but that would require some modifications to the frame and make bolt replacement very hard.

Midnight Specialist
02-16-2021, 06:50 PM
I had my mechanic just replace the TAB and nothing else, unless there was an issue. So far the OEM bushing and hardware look great and it's just the TAB being replaced. I agree that opening that can of worms is not great, but I like having the hardware on hand just in case.

Helirich
02-16-2021, 08:24 PM
I had my mechanic just replace the TAB and nothing else, unless there was an issue. So far the OEM bushing and hardware look great and it's just the TAB being replaced. I agree that opening that can of worms is not great, but I like having the hardware on hand just in case.

So where did you get inconel bolts?

Midnight Specialist
02-16-2021, 08:40 PM
DMC - Midwest. Their phone number is (815) 459-6439 if you want a set.

Helirich
02-16-2021, 09:07 PM
DMC - Midwest. Their phone number is (815) 459-6439 if you want a set.

Did they say the bolts were inconel? I notice it doesn't say that on their site.

Midnight Specialist
02-16-2021, 10:29 PM
They are not listed on their site. You have to ask them for the inconels, but they do have them.

Josh
02-17-2021, 10:40 AM
Did they say the bolts were inconel? I notice it doesn't say that on their site.

DMCMW offers alot more than what is said on the site. Best to send them an email or phone to ask.

Helirich
02-18-2021, 10:29 AM
$130 for two bolts. Wow! I can get class 12.9 for a couple dollars from McMaster. I think I might try to source the inconel elsewhere.

Josh
02-18-2021, 10:55 AM
$130 for two bolts. Wow! I can get class 12.9 for a couple dollars from McMaster. I think I might try to source the inconel elsewhere.

You can't thats why they are expensive. They have sold for alot more than that in the past as well.

Meanwhile I can comment until im blue in the face how I am using regular steel 12.9 socket head bolts with success (I still recognize the merits of Inconel) and it seems to fall on deaf ears.

Helirich
02-18-2021, 10:56 AM
I'm waiting for them to get back to me on the class of their standard tabs. If they are 12.9, I will buy them. If not I'm going to Order from McMaster. The 12.9 class is not much weaker than inconel.

Related question- the stock bolts that I see on my car look to be 6" or 150 mm long. I notice there is over an inch sticking out the nut. Do you think there is any possibllity that you would need that much shims? Or maybe they do that to keep more shank in the hole.

Comments welcome.

WHO1DMC
02-18-2021, 11:02 AM
A lot of the inconel bolts that people have used are the 718 alloy.




Dave B.

Josh
02-18-2021, 11:07 AM
I'm waiting for them to get back to me on the class of their standard tabs. If they are 12.9, I will buy them. If not I'm going to Order from McMaster. The 12.9 class is not much weaker than inconel.

Related question- the stock bolts that I see on my car look to be 6" or 150 mm long. I notice there is over an inch sticking out the nut. Do you think there is any possibllity that you would need that much shims? Or maybe they do that to keep more shank in the hole.

Comments welcome.

Its been established already in this thread that stock is class 8.8 and the replacements are 12.9 if using steel. Maybe re-read.
The bolt is a M12x140. anything else is incorrect. The shank and thread length is irrelevant, the portion pivoting is the bushing, not the bolt.

Michael
02-18-2021, 11:18 AM
I remember the days when Toby TABS brought 6 and 7 hundred bucks for a pair, and sometimes 4 figures.

Mark D
02-18-2021, 11:20 AM
In the grand scheme of things $130 isn't that expensive considering how critical those bolts are to the rear suspension. About 10 years ago I paid $150 for a set of inconel Toby Tabs and shortly thereafter there were sets going for $700-$800 on ebay. We're lucky as a community that DMCMW stepped in to have more bolts custom machined.

http://dmctalk.org/showthread.php?8020-Toby-TABs

There are a few documented examples of bolts breaking and causing serious damage to the rear fiberglass tub and SS quarter panel. You basically lose control of the car if the TAB fails, so there is potential for much, much worse.

http://dmctalk.org/showthread.php?13587-Reality-of-trailing-arm-bolts

12.9 class bolts are still a good upgrade from stock, but if I had to buy a set of bolts today I wouldn't think twice about the inconel bolts from DMCMW.

Helirich
02-18-2021, 12:15 PM
Its been established already in this thread that stock is class 8.8 and the replacements are 12.9 if using steel. Maybe re-read.
The bolt is a M12x140. anything else is incorrect. The shank and thread length is irrelevant, the portion pivoting is the bushing, not the bolt.

I reread and you said the stock were 8.8. You didn't say what the bolts listed on their site are. (They don't say either) They could have upgraded to 10.9 or 12.9. If the thread length is irrelevant, why not slightly shorter? (Save weight,lol)

Do I detect animosity? Why?

On the $700 bolts, that's ridicules. You can buy a shaft of titanium alloy for less than that and make quite a few bolts. I don't mind supporting venders and US companies in general, but I draw the line at robbery.

Josh
02-18-2021, 01:21 PM
I reread and you said the stock were 8.8. You didn't say what the bolts listed on their site are. (They don't say either) They could have upgraded to 10.9 or 12.9. If the thread length is irrelevant, why not slightly shorter? (Save weight,lol)

Do I detect animosity? Why?

On the $700 bolts, that's ridicules. You can buy a shaft of titanium alloy for less than that and make quite a few bolts. I don't mind supporting venders and US companies in general, but I draw the line at robbery.

Yes, animosity because you cant seem to help yourself when all the information is in front of you.

Last I checked, Titanium is not Inconel. Also, Im not sure what equipment you have access to but fabricating a bolt is not really a DIY job. If you were to make one in a lathe and a mill (head features) it would be a fairly involved process. Even after than, a titanium bolt has very low tensile strength just barely above class 8.8 steel bolts.

Finally, support your vendors. DMCMW is not out to rip anyone off. Its fine if you are too cheap for the inconel bolts, just get some steel 12.9s and install them.

Helirich
02-18-2021, 02:03 PM
Yes, animosity because you cant seem to help yourself when all the information is in front of you.

Last I checked, Titanium is not Inconel. Also, Im not sure what equipment you have access to but fabricating a bolt is not really a DIY job. If you were to make one in a lathe and a mill (head features) it would be a fairly involved process. Even after than, a titanium bolt has very low tensile strength just barely above class 8.8 steel bolts.

Finally, support your vendors. DMCMW is not out to rip anyone off. Its fine if you are too cheap for the inconel bolts, just get some steel 12.9s and install them.

Like I said, I did reread and the info was not there.

If you reread my post, I said "titanium alloy". Big differnce. Yes, I do have a lathe and mill. It's pretty easy to make a bolt. If you can't, you could pay someone a lot less than $700.

I do support the venders. I've spent over a grand just this week with DMC. I never said that they were ripping anyone off. Not wasting money is not "cheap".

Finally, why don't you calm down? If you don't want to respond, don't. If you get flustered over a few words, maybe go over to Facebook. I hear they censor out the meanies.

Josh
02-18-2021, 03:16 PM
I look forward to seeing your bespoke "titanium alloy" bolts that you fabricated yourself out of spite.

Better get off the computer and into the shop.

dn010
02-18-2021, 03:18 PM
First of all, :popcorn: It takes some kahunas to come to a forum and throw down with someone who has the skills and knowledge that Josh does.

Second, I too have been riding on 12.9s for nearly 20 years now with 0 problems. If you want to make your own short, long, strong, weak etc. bolts on your lathe then go for it - it would just be another option for you, right next to the 12.9s and inconel tabs.

Helirich
02-18-2021, 04:16 PM
First of all, :popcorn: It takes some kahunas to come to a forum and throw down with someone who has the skills and knowledge that Josh does.

Second, I too have been riding on 12.9s for nearly 20 years now with 0 problems. If you want to make your own short, long, strong, weak etc. bolts on your lathe then go for it - it would just be another option for you, right next to the 12.9s and inconel tabs.

I never said I wanted to make bolts. I'm going with 12.9's. I'm not doubting Josh's skills or knowledge. Ive read his build thread and I find it very impressive. I'm betting he has some other build projects that are equally impressive. (Hint, I would love to see them, Josh) In fact, if Im not happy with this engine, I might be doing business with him. (If he will sell to me) Having said that, I have confidence in my skills and knowledge also.

Sharing the garage with my Delorean right now.

65635

dn010
02-18-2021, 04:35 PM
You're stunned by $130 for bolts but might want to do an engine swap?

Anyway, go with the 12.9s and be done with it.

David T
02-18-2021, 04:44 PM
For all of the effort it would take to buy the materiel and make your own bolts, I can't see how it could be worth it for 1 set. Because this bolt is such a critical component in the rear suspension I don't understand why anyone would take any chances. There are counterfeit graded bolts of Chinese origin too so who knows if it is really a graded bolt if you buy it from anyone but the Delorean vendors. This bolt is a "Single Point Failure" item so you do not want anything questionable there. We aren't talking about a part so expensive that most can't afford to buy them anyway but how much is your safety worth? If your original bolts aren't bent or stretched, then just stay with them if you think new TAB's are too expensive. Now let's talk about how they are to be installed. Final installation and torquing AFTER a 4 wheel alignment with the right # of shims. With the full weight of the car on the wheels (very important so you don't add preload to the bushing) you torque the TAB's to spec. Be careful not to overtighten or you will collapse the steel collar inside the rubber bushings. Some owners like to also use jam (locking) nuts. I like to use indicator so you can see at a glance if anything moves. I also write the # of shims right on the frame so if you ever take things apart you can put the correct # of shims back. Once a year you should remove the shields and take a look at the TAB's and everything else up inside that area. If you ever find that the TAB is loose and some shims have fallen out you should replace the TAB and the bushing. The TAB may have stretched and the steel collar inside the bushing may have collapsed.

Michael
02-18-2021, 05:39 PM
I have wondered if it wouldn't be a bad "mod" to use a cable between the frame and trailing arm as a fail safe. It would have slack to allow movement but if the bolt ever broke, it would keep the trailing arm and real hub from moving to the point of wrecking you. Behind the wheel, the driver would know something was terribly wrong but still be able to control the vehicle to a stop. I would have no idea what a mod like that would use other than a heavy duty braided cable (perhaps plastic coated to prevent rust and scraping the frame coating) and maybe a clevis/cotter pin on each end.

Then again I don't run trailing arm shields, maybe that's what they were designed for?

dn010
02-18-2021, 05:46 PM
There was a thread of possible mods here long ago, I can't find it but did find this. It was a big enough deal that people were looking at ways to prevent catastrophe.
http://www.ohiodeloreans.com/bauerle_brackets.html



I have wondered if it wouldn't be a bad "mod" to use a cable between the frame and trailing arm as a fail safe. It would have slack to allow movement but if the bolt ever broke, it would keep the trailing arm and real hub from moving to the point of wrecking you. Behind the wheel, the driver would know something was terribly wrong but still be able to control the vehicle to a stop. I would have no idea what a mod like that would use other than a heavy duty braided cable (perhaps plastic coated to prevent rust and scraping the frame coating) and maybe a clevis/cotter pin on each end.

Then again I don't run trailing arm shields, maybe that's what they were designed for?

Delorean Industries
02-18-2021, 06:25 PM
Our next batch of inconel trailing arm bolts will be in production the third week of March. We are currently waiting on the raw material slated to arrive in March. This will be our first trailing arm bolt batch produced "in house" now that we have finished acquiring the firm previously making these (including a 96% employee retention rate bringing in 100+ years of combined machining experience into the fold at DeLorean Industries). With this batch we will be offering our bolt kit in two different ways compared to being in house only due to low volume not meeting even our demand. Stand alone retail of the bolts as a pair priced and also prorated when purchased with our bespoke suspension components.

Once we are caught up on TAB's we will begin production of all suspension hardware in inconel as well for our stainless chassis along with owners simply wanting something better than the generic factory grade fasteners.


EDIT-
Almost forgot to mention how you can differentiate our bespoke products even further moving forward. We previously select items were laser engraved and serialized accordingly by an outside service. This is now being standardized down to the batch after being moved in house. Essentially we will be able to track a product we manufactured down to the day and who made it moving forward shortly.

Helirich
02-18-2021, 07:03 PM
I have wondered if it wouldn't be a bad "mod" to use a cable between the frame and trailing arm as a fail safe.

I think this is certainly feasible. But I question the logic.

Has anybody died from a tab failure? I know some cars have been wrecked, anybody got any stats? Talking about "single point failures", there's lots of them on cars. There's some on helicopters. (Ask me how I know) Changing a $3 bolt that is 40 years old that has been a problem on a few cars is smart. Changing it to a $60 bolt is a bit over kill in my book. But you guys are welcome to do that. It's a free country. (For now)

You guys that are going on about making bolts. I said



On the $700 bolts, You can buy a shaft of titanium alloy for less than that and make quite a few bolts.

Will I do it? No way for a few dollars. Before I spend $700, yes I would.

If you guys are that scared of this failure, I highly recommend to modify the mount into a double shear setup. That would effectively double the strength of what ever bolts you run. (It wouldn't be that difficult)

Midnight Specialist
02-18-2021, 07:46 PM
Well, this tread blew up quick. I had my iconels installed the other day and the OEM bolts were slightly bent. Hardly noticeable, but you can see the bend. Needless to say I feel better driving now

Mark D
02-19-2021, 01:52 PM
Trailing arm bolt threads on DMCTalk are like "What is the best engine oil?" threads on BMW forums. :flamed:

Midnight Specialist
02-19-2021, 07:51 PM
But you want the best, right? ;-)

Timeless
02-24-2021, 12:06 PM
Trailing arm bolt threads on DMCTalk are like "What is the best engine oil?" threads on BMW forums. :flamed:
Exactly.... :mallet:

Helirich
02-25-2021, 02:16 PM
So I just got done changing my tabs. I have a few comments.

The bolts were tight as hell. It's not a big deal if you have a couple big 3/4" wrenches. I suppose the hex is metric, but 3/4" fits just fine. Once I removed the nut, I turned the bolt to see if it was bent. Mine were not, but worth a check.

I had the car up on jackstands and the bolts were very difficult to remove with the wheels hanging. I put some blocks under the wheel and put a little weight on them and the bolts came out easy. The driver's is slightly harder because it hits the tranny before completely out. I have a standard, so keep that in mind if you have an auto.

The bolts I removed were class 10.9. The previous owner told me they were original. (He was second owner) I bought three sets of bolts prior to beginning this job. The first was 12.9 allenhead bolts. I couldn't find 12.9 in hex head. The second, 10.9 hex head like what I removed and the third were 1/2" L-9s. I measured all three bolts. The 10.9s were .465" in diameter. The 12.9 were .475" and the 1/2" were .495". I couldn't measure the holes good, but I figure they are about .480"

I used the 12.9s for a couple reasons. They were stronger than 10.9 and the socket head was easier to install on the driver's side then a hex head. The 1/2" is probably the strongest of the three, but the holes would have to be reamed. The bushings could not be reamed inplace and I didn't feel like undoing them when they were in good shape. If and when they ware out, I will install the 1/2".

Someone mentioned the reaming the bushings might weaken them. This is obviously true, but I don't think a 10 thou. Skim would make enough differnce to worry about.

As to the discussion about strength, I've seen trucks that weigh more than twice this car with 1/2" leaf spring bolts. Of course they are in double shear, but I really think it's the bending fatigue that gets these bolts when they fail. So maybe we shouldn't be looking at yield strength. Just something to think about.

One ther thing I will mention. I put all the weight back on the tires before final torq was applied. (That way the rubber bushings are not being twisted at rest)

David T
02-25-2021, 03:00 PM
Sounds like everything went well but you didn't mention anything about shims. If there weren't any that is a cause for concern. Every car I have ever seen had them unless they were removed. There are always *some* amount of shims on each bolt. Maybe plan for a 4 wheel alignment in the near future. Yes, the problem is not so much shear as a bending load on the TAB's. To make it worse it is a cyclic bending load. That is why torque is so important. By torquing the bolt near it's elastic limit you make it immune from the cyclic loading. You induce a tension load above the bending load.

Helirich
02-25-2021, 03:17 PM
Sounds like everything went well but you didn't mention anything about shims. If there weren't any that is a cause for concern. Every car I have ever seen had them unless they were removed. There are always *some* amount of shims on each bolt. Maybe plan for a 4 wheel alignment in the near future. Yes, the problem is not so much shear as a bending load on the TAB's. To make it worse it is a cyclic bending load. That is why torque is so important. By torquing the bolt near it's elastic limit you make it immune from the cyclic loading. You induce a tension load above the bending load.

Yea, it had shims. I just put them back where they were. After I get it on the road, I'll decide on an alignment.

David T
02-25-2021, 03:46 PM
The things to watch are;
Is the steering wheel centered as you drive on a straight, flat road?
Do you have an equal # of turns left and right, lock to lock? Does the wheel return to center while moving? Does it shake?
Does the car tend to wander? Is there any looseness or play in the steering?
Are the tires wearing evenly? Make sure they have the proper pressure as listed on the glove box door label.
When you accelerate does the car want to go to one side or the other?
If the date codes on the tires is over 7 years old they should be replaced.
Before you go for an alignment check for anything worn, loose. or bent. Lubricate the tie rod ends and the ball joints. Spray the bushings, spring perches and column bushing with silicone and the 2 universal joints with WD-40. Empty the car and have a 1/2 tank of fuel. A good shop will do a though visual inspection before an alignment and check the balance on the tires.