Camaro Dave
Jan 20th, 06, 11:28 PM
A buddy of mine who used to work in a frame and alignment shop told me that after replacing the bushings on the lower control arms, you must torque the control arm bolts with the engine in the car. I am not doubting my friend, it is just that there is no mention of this procedure in any of the manuals.
ept000
Jan 20th, 06, 11:34 PM
True... You want the car at its riding height before you torque any of the bushings.
HarleyD67
Jan 21st, 06, 01:14 AM
If you don't you will load the suspension and cause it to bind up when the weight is added later.
1969ss
Jan 21st, 06, 02:29 AM
This is for a 1969 chevelle, the 1969 chassis service manual says.
After you install the control arms, bounce the vehicle up and down to centralize the bushings, then tighten the bushing collar bolts to 45 ft lbs.
It's a little hard to find in the manual, but if you look real hard it should be in yours also, maybe. Good luck
Rob
JohnZ
Jan 21st, 06, 07:29 PM
It's also in your Assembly Manual, in the UPC 3 Front Suspension section, on the sheet that shows installation of the upper and lower control arms:
"NOTE: With the hub and drum attached and the spring in position, tighten lower control arm attaching nuts to specified torque with vehicle weight on the lower control arm assemblies."
The outer bushing shells are locked solid in the control arms, the inner bushing sleeves are locked solid to the frame by the serrations on their ends (when the bolts are torqued), and ALL control arm motion takes place ONLY in the rubber portion of the bushing, which is bonded solid to the I.D. of the outer shell and to the O.D. of the inner sleeve. That's why the torsional stress in the rubber must be zero (neutral) at normal ride height. If not, the bushing rubber will be "wound up", and that additional torsional stress will result in rapid failure of the bushing.
:beers:
X33D80
Jan 21st, 06, 07:37 PM
If all fasteners were tight before mounting the engine, would it be sufficient to loosen all nuts, bounce the car some, then tighten them again?
JimM
Jan 21st, 06, 08:12 PM
yes... and this procedure applies in the back, too.
Camaro Dave
Jan 21st, 06, 09:47 PM
Thanks for the replies......It makes sense. When the engine was put back in the car, the car sank three or more inches. I realize now that if the control arm bolts ( upper and lower) are tight, it would cause the bushings to bind.