Rear IRS Subframe Bolts

[GT Pony]

Has anyone checked the torque on their rear subframe bolts? The shop manual shows the torque to be 129 ft-lbs for the big main bolts and 41 ft-lbs for the smaller bracket bolts.

Thought while under the car I'd throw a torque wench on them and just check the torque to make sure they are to spec. I've found fasteners before that are under torqued.

Strange thing is the shop manual says to throw the bolts away and use new ones if they are removed. What's that about? Is Ford paranoid that the bolts are weakened if removed?

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[BmacIL]

I checked the torque after about 100 miles twice: once after doing the CB005 and the other after doing springs. Each time they were still tight.

 

[Dominant1]

Many bolts are one time use only. if you use them again they may work themselves loose over time so replace them with new ones. I know a guy who reused his crank bolt torque it to spec and it came loose later and his motor failed!

 

[GT Pony]

Many bolts are one time use only. if you use them again they may work themselves loose over time so replace them with new ones. I know a guy who reused his crank bolt torque it to spec and it came loose later and his motor failed!

I'm not planning to remove any of the bolts, but just put a torque wrench on them and see if they tighten up any more. I don't think that would affect the bolts the same as removing time.

Still can't see why these particular bolts would have to be thrown in the trash and new ones installed if removed unless they are designed to stretch some way on a one time basis only. :shrug:

 

[GT Pony]

I checked the torque after about 100 miles twice: once after doing the CB005 and the other after doing springs. Each time they were still tight.

So you had them totally removed when doing the CB005 mod?

 

[Mustang_Lou]

Those 1-time bolts are called "torque-to-yield" bolts but I just ordered the Steeda alignment kit that goes with CB005 that'll require some rear cradle bolts to be removed so now I'm wondering if it's the same bolts you're talking about OP.

 

[Dominant1]

Pm steeda or the bmr guys and they will tell you if those bolts are 1 time only bolts. My guess is they are not based on the fact that they dont provide hardware with the parts. Both companies are reputable and if they were needed they would provide them.

 

[wildcatgoal]

I have removed the rear IRS cradle blue bolts numerous times and they do not work loose. I don't use loctite, either. For those particular bolts, it is not a concern of mine. I am personally more concerned about ensuring I thoroughly clean each bolt's threads and the threads it will be installed into before I reinstall a bolt. Eventually, after finally settling on my suspension more-or-less, I did replace most of the bolts that Fords says are torque-to-yield, but mostly just to have fresh bolts that aren't beat up by repeated removal and installation.

 

[BmacIL]

So you had them totally removed when doing the CB005 mod?

Correct. I've had them totally removed twice. Once to do CB005. Another to do springs. Both times I drove for ~100 miles and then rechecked torques. Not even a budge and clicked immediately.

I was also very careful that they threaded in by hand most of the way, ensuring there would be no cross-threading. They last as long as you don't damage the threads.

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