ph31mwl

While I had the body off the frame and the frame apart to rebuild the suspension, I rebuilt the A Arms on my 65 Roadster. The instructions said not to install the a-arm bushing retainer bolts until the frame is back together, the engine and transmission installed and the body is back on the frame. I am at that point now where I can install the retainer bolts. The more I tighten all I am doing is squishing the rubber bushing. There must be some point to stop but I am unable to find any instructions. My question is how tight to I tighten the bolts? Thank you very much for any guidance you can provide.Mark

63 340HP

Can you post a photo so we can see the bolt(s) in the question?

ph31mwl

63 340HP, I will take pictures and try to post tomorrow morning

Mark

rongold

PH31MWL, I know the bolts you are talking about---The ones that screw into the ends of the control arm shafts. The 65 AIM does not specify any torque values for them, but the 66 & 67 aim's specify 45-55 foot pounds for the lowers, but no specs for the uppers. The uppers are smaller than the lowers if I remember correctly. I don't have access to my car right now, but If the uppers are 5/16" bolts, I would go about 25 foot pounds, and if they're 3/8" bolts I would go about 35 foot pounds.


RON

leif.anderson93

The upper collar bolts on a '67 call for 45 lb ft. I check both uppers and lowers once a year to insure they're not backing out (had this happen once). With a box end wrench I just tighten them until they're good and tight. Unless you're using a cheater bar, you really can't over tighten them. The bolt will eventually tighten. Crank away!!

buns

JohnZ

The upper control arm bushing retainer bolts don't show a part number or torque spec because the upper control arm was received at St. Louis as an assembly, with the bushing retainer bolts already torqued at the supplier (Chevrolet-Warren) while the upper arm and cross shaft were clamped in a fixture that established the angular position of the arm relative to the cross shaft while the bushing retainer bolts were torqued; St. Louis never touched them.

SW Vette

So lowers 45-55 and uppers 35-40 ft/lbs then? Seems like a lot for those bolts. Mine were loose when I checked, but didn't want to overtighten them and squish the bushings too flat.

ph31mwl

63 340HP,rongold, leif.anderson93, buns, John Z and SWVette, thank you all very much for your responses. I was unable to find the answers anywhere and I want to do this correctly. 63 340HP, I have attached a picture (I hope) of the bold and where it goes in the upper control arm. The lower is the same except it is a bigger bolt. Based on the recommendations and the chart that “buns” has provided, it looks like the uppers are torqued to 35 – 40, and the lowers torqued 45 – 55.Thank you so much for providing this information.Mark

rongold

The bolts have to be tightened enough so that the washer contacts the serrated end of the bushing inner sleeve and pushes the opposite end of it against the shoulder on the shaft. The sleeve is supposed to be squashed between the shaft and the washer under the bolt. This is why you are supposed to torque the bolts with the car on the ground and sitting at normal height. When the suspension goes up & down those bushings ARE NOT supposed to spin on the shaft. The rubber is supposed to "twist" and the sleeve stays put.


RON

A-Snake

Because they were received as a finished item, the A Arms were painted gloss black including those bolts, washers, cross shafts and even paint on the bushings.

leif.anderson93

Excellent chart Buns. Source??

63 340HP

You have the right spec.

The large washer with the small hole will bottom on the shoulder at the end of the threads. This provides enough crush to wedge the inner rubber to the cross shaft, so the future movement is twist in the rubber bushing between the inner and outer edge. You want the car at ride height for the final tightening so the rubber inner edge on the cross shaft does not move, and so the rubber outer edge moves the least amount of rotation to minimize twist away from normal ride height in a bump.