Loud rattle or knocking

[stoneymonk]

Hey guys love these old cars,keep me busy with maintenance.When i apply the brakes this only happens sometimes i get a loud rattle coming form the middle to rear end of the car,also a loud knocking when i drive on eneven surfaces on the drivers rear.What could it be and are they related,i think possibly either rear stut mount or trans mount?.Or the car in question is a 95 lumina 3.4 dohc,had done complete brake job in the last month.Oh forgot how and what type of to use refrigement to top up for ac.

[robertisaar]

the a/c uses r134a... a 2lb system too if its the same as my 95 MC

[stoneymonk]

Thanks bud,any ideas on my other two issues?

[robertisaar]

struts and/or trailing arms?

i had my struts go bad in the back and made ridiculous noise over even very small cracks/bumps. alignment also went to shit, so check your tires for wear. then i had a trailing arm go to shit(the mount broke loose/rusted from the frame) and the wheel was allowed to rotate about its axis however it wanted.

those would be two good places to start looking.

[stoneymonk]

Thanks will check them and post results

[walterdude]

Don't know how a 95 Lumina is but, if it has a transverse mono-leaf spring, the pads on the tip of the springs can wear/fall off... THAT made my 93 sound like the whole car was gonna fall apart. They're cheap and there are many posts here about it... Also the top strut mounts can wear.... Everything else that was mentioned can be checked as well....
Good Luck,,,
Tom....

[robertisaar]

leaf spring is a gen 1 only, MC and 95-up Lumina are 1.5, have struts all around

[stoneymonk]

How do u tighten the top bolt of the rear strut,its keeps turning,cant figure out how to lock the allen screw and tighten the nut?

[savannaz34]

the a/c uses r134a... a 2lb system too if its the same as my 95 MC

2.25 pounds in my 91 lumina z34

[savannaz34]

How do u tighten the top bolt of the rear strut,its keeps turning,cant figure out how to lock the allen screw and tighten the nut?

can you get an impact on the nut? i dont know,ive never had the issue nor have i even looked at the back struts

[robertisaar]

2.25 pounds in my 91 lumina z34

that uses R12. my wifes 90GP with 3.1 has the same setup: 2.25lbs of r12.

[savannaz34]

that uses R12. my wifes 90GP with 3.1 has the same setup: 2.25lbs of r12.

actually im pretty sure mine is a 134 system,i will double check tonight when i go to the shop to do an oil change on my quad tonight

[pocket-rocket]

95 was the first federally mandatory year for any auto maker to use R-134a. Anything before that used R-12. As for the strut nuts, you're supposed to take the upper strut mount off, put it on the new strut, and tighten the nut with an impact while you hold the shaft to keep it from turning. Once I tried mine without an impact though, and I very stupidly had to use vice grips on the shaft to keep it from turning, but luckily the steel rod was hard enough not to get damaged. I would second struts too. My 91 sounded like the back tires were going to fall off when the struts went bad. I freaked out because the rear bearings and everything felt fine and couldn't pinpoint it, but I decided to get some new struts for some reason. I want to say it was because I saw one of them had started leaking. Once I had the new ones on, the sound stopped.

[stoneymonk]

Let me see if i undestand the directions,there are 4 bolts inside the trunk amdd two on the axle bracket,remove those and and take strut out and use impact on top bolt of strut to loosen and install new stut mount and retighten top bolt and reinstall stut?

[pocket-rocket]

Si senor.