67 rear leaf spring

[Terry W.]

Having an issue with my rear spring the second and third leaf from the bottom are in helicopter mode , they are moving forward on the drivers side, I have already jacked the car up , dropped the two outer spring bolts, backed off the 4 centre diff bolts and realigned the leaves,dropped it back on the ground and tightened all back up, but it's doing it again,( plastic spacers are in place) is it torque related?
thanks
Terry

[Timothy B.]

Re: 67 rear leaf spring

Terry,

I am not sure I can offer a answer to your problem except to say the spring liners are sort of H shaped to capture the leaf below and above. This may help keep them straight with each other. Is the center bolt torqued tight.

[Gene M.]

Re: 67 rear leaf spring

Terry,
You may have a parts issue or even multi-parts issue. The original differential cover is threaded for 9/16" bolts, some replacements are smaller. Thread position is critical to retaining spring in place. The lower plate with the 4 holes are close fitting to the bolts on originals. Original leaf spring is very close fitting with the four 9/16" bolts so it stays in position. Replacement springs are typical too narrow. The only thing that keeps the spring from spreading is the tight fit of the four 9/16" bolts trapping the spring in.

Now if any of these parts is "too loose" fitting the spring will spread out. My suggestion if clearance is excessive is to cut a piece of steel plate long enough to span the spread of the 9/16" bolts and width of 1/8" less than the spring stack height. Steel thickness of some where between 1/16" and 3/16" is a start. Add or reduce thickness to fit snug. Bend the ends so as to curve with bolt shank to maintain in place and not fall out. Put the steel on the inside as not to be visible. Steel sleeves (close fitting 1/16" wall) shorter than spring stack height placed on the inboard 9/16" bolts also works but may be more visible. If judging is not a concern sleeves on all four bolts may give a better fit securing spring.

[Tim G.]

Re: 67 rear leaf spring

As Gene noted, the aftermarket springs tend to twist. When I returned the original spring to my car, this twisting ended.

[Terry W.]

Re: 67 rear leaf spring

thanks for your reply's ,the car had undergone a body off restoration , so I am unsure weather it retains the stock spring or an aftermarket set .will do some measuring.

cheers

[James H.]

Re: 67 rear leaf spring

Again if judging is not an issue, you can't beat fiberglass. I put one on my 67 and it rides great.. I put a reproduction on my 68 and it's taken 2 years to settle out to the correct height.
Jim