Changing Rear Shock Absorbers. Astra-J Hatch. Replace or reuse bottom bolts?

[Big Dave2]

Hi folks,

I'm about to change the rear shocks on my car, and according to the info on the Vauxhall workshop manuals website the bottom bolt that connects the shock to the suspension arm should not be reused, but a new one fitted.

The torque settings given are to tighten initially to 150 Nm, and then tighten a further 65 degrees. This suggests to me that it's a stretch bolt. Am I correct?

In all the years I've replaced shock absorbers on various Vauxhall cars, this is the first time I've ever seen mention of replacing the bolts.

So, do I throw caution to the wind and just reuse the bolts, making sure they're FT, and a bit of thread lock for good measure.

Or should I replace them as suggested?

Thanks.

[Jetcolour]

I changed my rear springs a year ago and I did not replace the bolt and have had no issues.

I just found information on the internet about how to do and didn't see any one mention this. Albeit a workshop manual will have more detail in it.

I can't see why you should have to replace them. It could be because the end of the threads and top of bolt get rusty and can get damaged when removing them.

[steve1412]

I  changed my rear springs a year ago and I did not replace the bolt and have had no issues.

I just found information on the internet about how to do and didn't see any one mention this. Albeit a workshop manual will have more detail in it.

I can't see why you should have to replace them. It could be because the end of the threads and top of bolt get rusty and can get damaged when removing them.

they are renewed for the very reason that they are torque to yield bolts. most bolts tend to get torqued to a set figure, sometimes with the addition of threadlock compound. Reusing any bolt that has gone through a torque and angle tightening sequence is a risk,  as the bolt deforms, especially in strength and clamping force.
i will re-use a standard torque bolt but any bolt that also has a tightening angle as well, gets binned and i use a new one. especially on suspension, engine and brakes

head bolts are angle tightened, no one with knowledge re-uses them

[Rusty2009]

Changed my shocks twice now front and rear reused all bolts no problems.

[niteram]

While I completely agree with what Steve1412 says regarding the replacement of "stretch" bolts on heads etc, the synical side of me thinks it's just another way to dip their hand into our pockets.

[Big Dave2]

An update on this. Sorry, I haven't been around much just lately.

I ended up paying a local mechanic £50 to change the rear shocks for me as a recent operation on my leg meant getting down on my hands and knees to do the job was going to be painful. I did try to see if I could book into one of these self service garages (the one local to me is called "This is your garage" which is based at Culham in Oxfordshire. I've no connection with them btw). But due to Covid-19 restrictions they cannot allow anyone to rent ramp space at the moment. He did mention that there were a couple of mechanics who use the place as their working base and put me onto one of them.

Anyway, long story short, the mechanic used the same bolts. I did mention about replacing them to him, and that there was a suggestion of tightening them to 150 Nm, and then through a further 65 degrees. He said it wasn't necessary unless the bolts had damaged threads, or damage to the head of the bolts in getting them out. He's done loads on different cars in his career history and not had to replace any yet.