Torquing The Rear Leaf Spring Retainer?

[Don L.]

Soooo, yesterday, my trusty assistant and I (he can jump in here if he wants to admit working with me) are installing a new 9-leaf spring on my '72. Not without some complications, we get all back together and when we put weight on the spring to torque the 4 retainer bolts, we can't get the specified 60-80 ft lbs. It feels like I'm going way too far with the wrench and the retainer ears start to bend. This causes me to think that I'm getting a false torque reading due to the "soft" base of the bending retainer, and stopped. The bolts feel plenty tight but I thought I should ask this group for advice before proceeding. Help please.

[Paul B.]

Re: Torquing The Rear Leaf Spring Retainer?

...did you do it with the car up in the air??? I believe it's supposed to be done with the weight of the car on the spring itself so your tightening it when it's "flattened out" vs no weight on the car and the spring is very arched.

[Don L.]

Re: Torquing The Rear Leaf Spring Retainer?

The weight of the car WAS INDEED on the spring. The car was "in the air", but was on my 4 post lift, giving me the weight of the car on the spring, but the convenience of standing under the spring to work.

[Larry M.]

Re: Torquing The Rear Leaf Spring Retainer?

Don:

I experienced a similar thing. I just was not certain that the retainer or the cast housing ears were strong enough to take the stated torque. So I basically tightened them by hand until I thought they were tight. The measured torque after this was about 1/2 the book value. (Disclaimer: Never-seize was used on the bolts, which will lower the required torque numbers)

I my case, BUBBA had cross-threaded one of the four spring mounting bolt holes, so I was very cautious when assembling the spring. I rethreaded the bolt hole in the housing, but it was a bit "loose" compared to the others. I have had threads strip out before when I tried to tighten to the book numbers.....especially in aluminum

Larry

[Jeffrey S.]

Re: Torquing The Rear Leaf Spring Retainer?

We used 2 different click type torque wrenches, both set to only 50 ft lbs. and neither reached the click point so we stopped before we broke/stripped something.

[Alan S.]

Re: Torquing The Rear Leaf Spring Retainer?

Hi Don,
Didn't the width of the spring leaves change at some point?
If the leaves are narrower, wouldn't that allow the plate ears to deform since they're not completely supported by the leaves?
Do you have the right spring?
Just a thought.
Regards,
Alan

[Don L.]

Re: Torquing The Rear Leaf Spring Retainer?

Good question Alan. Thanks for pointing this idea out.

The very incorrect replacement spring that was on the car was approx 2" wide. The new spring is more like 2 1/4" wide. Accordingly, wouldn't I expect to see an improvement with the wider spring over the narrower one? I should have checked torque before disassembling - darn!