New Leaf Springs - Part 99

The Grab-A-Trak 5 leaf, standard height springs have done a good job of keeping the rear tires from making contact with the rear quarter panels but are quite stiff.  I've continued to use them, and received them in the first place, because the Grab-A-Trak 4.5 leaf springs in standard height have simply not been available.  They first became unavailable in February 2020 and I've not found them since.  I ordered them from Top Flight Automotive as part of a Father's Day sale many months ago and they were just able to fulfill the order.

At this point, I could have purchased a pretty serious rear suspension setup with the amount I've spent on three different sets of leaf springs. Unfortunately, I don't know that I really could have guessed the challenges that I would have.  I'm not sure which of them I will keep but they might come in handy if I continue making changes to the car.

While all of the leaf springs were out of the car, I set them side by side and took the following picture.  The first two sets of GAB leaf springs look identical in terms of leaf edges and plastic bushings.  However, the new set of leaf springs (in middle) look rather different except for the clamps.  They also lack the Grab-A-Track paint on the back and any labelling to confirm they are that particular brand.  

The new leaf springs have APM 12 22 42-329 stamped into the eye.  The last part (43-329) can be found online as a 4 leaf truck spring but it is definitely a 4.5 leaf spring.  With the differences I see between these and the last sets, I suspect I was just provided with a generic set of springs rather than actual Grab-A-Trak.  I installed them anyway as it would be a pain in the ass to return them.

I measured the various springs to check the difference.  I don't expect this to be reliable for anything as the spring rates are different and the 4.5 leaf springs have not been used.  Regardless, the heights were:

5 leaf        8 7/8"
4.5 leaf     9 7/8" (unused)
4 leaf        7 3/4"

I'm not positive, but the research I've done indicates the following spring rates for GAB springs.  I can tell just by bouncing the rear of the car by hand that these are not near as stiff.  I actually think they might be less stiff than the original 4.5 leaf springs.

195 for 5 leaf
175 for 4.5 leaf

I also took a few measurements before I started replacing or even moving around the car.  The heights were as follows:

Passenger Front     24 7/8"

Driver Front            24 13/16

Passenger Rear     25 9/16"

Driver Rear             25 5/16"

Update: I drove around with all the nuts finger tight to let the suspension settle.  I then torqued everything down and checked the height.  It is presently at 26 7/8".  It will likely settle a little more.  It would be great if it were a little lower but certainly not an inch.