Some of us still have the older Econoline and would like a slight front coil spring boost. My '95 E-150 Chateau 5.8L with the factory tow package is still running the original front spring, which is heftier from the factory due to the tow package.
The hot ticket for a good variable rate spring and a very slight lift was the venerable Moog CC880 (not the 'S'). 16" free height, 13" installed, 589 lbs/inch, 1,850 lb rating. The closest Moog listing is the CC878 15.75" free, 13" installed, 589 lbs/inch, but 1,687 lb rating.
With the CC880 on endless backorder and now showing discontinued, it seems all that has been available lately is the CC880S which often reports too tall, and too stiff for smaller gas engine or E-150 applications.
While chasing the CC880, I decided to link from Moog to online resellers. I ended up at O'Reilly with their "Precision" branded spring and guess what? Specs show to be identical to the CC880. 16" free height, 13" installed, 589 lbs/inch, 1,850 lb rating. The only difference I could find was their reference to 3/4" coil vs 0.78" Moog spec. In stock and reasonably priced with a 20% off coupon code.
Since I knew it was too good to be true, I copied and pasted the Precision branded part number and searched, and found an old link that showed a prior part number of "GCC880". Hmmm... I pulled the trigger, thinking these things are likely sourced from the same overseas manufacturer, possibly in a private label box. If the specs are correct, I should have an equal to the CC880 spring. I would even venture it will end up measuring out to 0.78" with my caliper.
Link for specs. Notice they list only E-350 application. The CC880S has a 3,006 lb rating on the springs, which is likely why folks complain about stiffness unless you have a really heavy engine.
I'll update when I get them installed with before/after measurements.