I had to replace my lower control arm. (I was coming home after work at 2:30am during a snow storm. I was turning left and the car slid into the curb that I didn't even see. The curb was hidden by the snow. Needless to say I bent that lower control arm.)

I got the new arm in, but I have a question about what they say in the service manual:

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Ball joint to steering knuckle nut
Tighten
First pass 37 ft lbs reverse nut 3/4 turn. Second pass 37 ft lbs plus 30 degree rotation.
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That is exactly what it says. I want to know what they mean by "plus 30 degree rotation"?

It says something like this again here:

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Lower control arm to rear frame bolt
Tighten
74 ft lbs plus 180 degree rotation.
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What do the mean here by "plus 180 degree rotation?

The manual is the 2006 Chevrolet HHR Service Manual, A SUV volume 1 of 2 GMT/06-A-1. The section these quotes can be found in is Front Suspension, page 3-29, Lower control arm replacement.

Can you help me understand what they mean by plus x degree rotation in both of those steps?

 

Confusing ain't it, OK here goes....

"First pass 37 ft lbs reverse nut 3/4 turn. Second pass 37 ft lbs plus 30 degree rotation."

OK set your torque wrench to 37 ft lbs and tighten the nut until it clicks, then back the nut off 3/4 of a turn(it helps if you mark it with a wax pencil or something). Then tighten the nut again to 37 ft lbs and then tighten it a bit more, 1/12th of a turn...just a little tweak really.

"74 ft lbs plus 180 degree rotation."

OK set your torque wrench to 74 ft lbs and tighten the bolt until the wrench clicks, then give the bolt 1/2 turn more...just like the nut above, mark the bolt with something.

I know it sounds odd, but following the directions gets the fasteners torqued and pre-loaded to factory specs.

 

That will work fine, But what they actually mean is go to the tool store and buy (less than $20) or borrow a "torque angle gauge" then figure out how to use it. Basically you get that rear bolt as tight as a 1/2 inch breaker will go after you get 74 ft lb. I could not get the thing to go anywhere near 180 degrees more. I don't think any body actually pays attention to torque angles except in the case of "stretch bolts", which these are not.

 

Ok guys, thank you very much for the clarification. I thought as much, but wasn't sure.