Control arm replacement nuts

[valleyman]

In looking over the shop manual before starting the project of putting on my new Mack & Zack control arms, I noticed that the manual advises to discard the used nuts replace with new ones. Local L/M parts guy called me back after I ordered them over the phone and says he got a "J code" when he tried to order replacement nuts -- which apparently means they don't exist. Part #s were W705295S428, W704991S428, W704662S428, and W50215S428. Anybody just reuse the OEM nuts and experience no problems?

And for those of you who are as bone headed as I am, realize BEFORE you start to round off the lower control arm rear nut, that it is the tang that forms part of the nut and butts up against the axle housing that prevents the nut from turning and not the factory-applied loctite. :bigcry: Doh! Every once in a while I amaze myself with the new and unanticipated levels of stupidity that I am capable of achieving.

[Warpath]

I'm surprised the parts guy said that. Fasteners should be shelf items readily available. Make sure he is looking for the correct parts.

It is a good idea to use new nuts and bolts. First, the fasteners can corrode and mess with your torque spec. In other words, you will get a false torque reading because the corrosion is creating extra torque. Second, when the fastener is run down, it removes some of the original corrosion protection. Using them a second time allows for more corrosion which may or may not affect its performance. Thirdly, the threads can wear out when used multiple times and affect performance. Lastly, torque specs are typically set with new fasteners. However, all that being said, if your MM is new and the fasteners are still clean with no dirt or rust, you can get away with using them a second time. Make sure you torque them properly. I also suggest you get a paint marker and draw a straight line from the nut to the mating surface (frame, axle, arm, etc.) and another line from the bolt to its mating surface. Keep an eye on it. If the lines don't line up anymore, things have loosened up.

Some of you may think I am overreacting. However, I deal with this kind of stuff day in and day out. You should always be extra careful when messing with parts that keep the dirty side of the vehicle down.

[EbonyMarauder03]

I just checked all the hardware for the rear arms, both long and both short. Some of the hardware did change part numbers, usually the last three numbers change. The only piece that had an issue was the nut for the front half of the long arm, the rest looked available. I have a complete list if you want it.

As for stocking these pieces, it's not something a dealer would stock. It's very rare that any of these arms are replaced, except for our mod. You'd more likely find a dealer stocking the nut for a ball joint or a pinch bolt for a strut since these are maintainence items. Also if you poke around your car enough you'll find that a lot of hardware isn't common. Engineers only make money and keep their jobs by coming up with new and add stuff.

[Warpath]

... Engineers only make money and keep their jobs by coming up with new and add stuff.

Uh, no. We use whatever works and can be assembled quickly. If that means using something new, then we do it. We don't sit around thinking about changing something so that people are forced to buy it. It costs us a lot of money to change things around. So, we avoid it.

[SergntMac]

I recycled the OEM nuts and bolts without any problems. I also ordered a set of fresh nuts and bolts for the engineering stage, be advised that uppers and lowers are different sizes. I had no problem ordering from the parts department, just a two day wait from the depot. Sorry, I can't seem to locate my sales reciept right now, when I find the correct part numbers, I'll confirm the above, or post the corrections.

[valleyman]

[QUOTE=EbonyMarauder03]I just checked all the hardware for the rear arms, both long and both short. Some of the hardware did change part numbers, usually the last three numbers change. The only piece that had an issue was the nut for the front half of the long arm, the rest looked available. I have a complete list if you want it.

EbonyMarauder03 - could you pm me or post the part #s, please. Warpath has got me convinced, given the torque values applied to these fasteners, that I might as well use new and "unstretched" ones while I've got it all apart. Do it once, do it right etc.... Those control arms sitting on my bench instead of my car are really starting to get to me. Thanks, guys.

[valleyman]

Thank you too, Mac; just saw your post.

[Petrograde]

could ya post the #'s here please?