New Leaf Springs A.K.A. Six Weeks of Rolling Around Under a Van in Sweat, Metal Shavings, and Gravel
Apparently 20 years is about the life span of a spring leaf pack on a 3/4 ton truck, because the amount of sag on our rear axle was not normal. We determined to replace them along with the rear shock absorbers in hopes of getting a better ride in the van (hehe). My buddy Mike offered his assistance and assured me that with two people working the job would be done in a weekend. Silly Mike, the Big Mountain Jalopy is actually a sentient being, and it would no sooner let go of any part of itself than you or I would let someone remove our own arm...
It started out fine. Mike and I began by removing the old shock absorbers. They came out without issue until the last bolt, which wouldn't budge. No worries, we'll just soak it in PB blaster and try it again tomorrow. Little did we know that this was the beginning of the end of my sanity. We moved to work on getting the old leaf springs out. Each leaf spring is held onto the frame of the van with two through-bolts, for four connections total. Because those bolts are essentially carrying the whole load of the rear of the vehicle, GMC actually hired King Kong to come work at their factory and tighten these bolts on their vans. That, coupled with about twenty years of rust (this van is originally from New Jersey) meant that the leaf springs might as well have been welded to the frame. Despite this, we were able to remove precisely 1 of the through bolts using conventional means.
Enter the unconventional means. After soaking everything liberally in PB blaster, we came back the next weekend with fire. Mike manned the propane torch, and I would periodically whack away at the bolt with a hammer. The only thing this accomplished was burning the rubber bushing that goes around the pivot point at either end of the spring, and making my backyard smell like someone had been peeling out in their shitty modded Civic. But the bolts didn't budge. The next plan was to try the torch again but with more force. So instead of a normal hammer, we got our hands on an air compressor and a pneumatic hammer. Even though the air powered hammer was able to pulverize the brick-sized rocks that line my flower beds (I had gotten frustrated and turned to finding out what I could destroy with air tools), it was still not enough to break these bolts through. The only thing we hadn't tried yet were power tools. With a reciprocating saw, we were able to finally cut through the bolts. Each bolt took about ten minutes to cut through, and expended two saw blades due to the hardness of the steel. The axle u bolts had the nuts rusted onto them so badly that my attempt to break the torque with a breaker bar simply sheared the u bolt at the nut, giving a new, more literal meaning to my breaker bar. With the spring through bolts out, but no fresh sawzall blades left, the axle u bolts had to be cut with an abrasive cut-off disc.
That's one way to do it...
The right side nut on the u bolt on the left of the photo is where I snapped the bolt using my own strength ᕙ(⇀‸↼‶)ᕗ -with the help of a 24" breaker bar-
Here are the old leaf springs with the old shackles still attached. Not even going to bother trying to get those off to reuse them.
At this point our "two day job" had eaten up four weekends. But at last Mike and I were to a point where the new parts could go in. It took both of us to install each leaf spring, one person to hold up the 70+ lb spring pack and the other to persuade the ends into the shackle mount on the van frame using a pry bar. With the new springs in place, the only thing that remained was to tighten everything down and install the new shock absorbers. But we were not in the clear yet. I had ordered new shocks online from Rancho, because quite honestly I don't know anything about suspension parts and they said they fit my van, and Rancho was a brand I had heard of before. As far as the fit, that was only half-true. The shocks fit, but the mounting hardware they came with did not. The OEM shocks on the van had a rubber bushing with a steel tube through a hole in the middle that the bolt goes through and mounts the shock tube to the axle. The new shocks also had a rubber bushing (the part in the photo where the white paint is flaking off to expose the black rubber underneath) but no steel mounting sleeve was installed through the center. Instead, in the package were these little folded metal tubes made out of paper thin and lightweight metal. These mounting sleeves are supposed to fit into the bracket on the axle and withstand the manufacturer-specified 140 foot-pounds for that connection. Have a look at what half of that torque did to one. This was after I had deformed the bracket on the axle with the torque wrench because the sleeves were so short that they didn't even come all the way to the ends of the bushing. If someone from Rancho is reading this, I am not impressed. Rant over.
If you're going to tell your customers a part fits their car, make sure the included mounting hardware also fits!
I bought stainless steel spacers from an Ace Hardware that were roughly the correct size and used those instead.
Finally, with everything back together, the BMJ was looking a lot better. Got new tires on it too! We went on a trip up to Flagstaff and everything held together!
Driver side and passenger side rear suspension all put back together. Look how shiny!
I am happier than ever to have this job done. Just look at how pissed I was in that first photo. The van rides higher and handles a bit less like a giant marshmallow. With the heavier leaf springs installed, our van went from a 1,300 lbs load rating to 2,000 lbs, a full ton! Now its time to load it down with all our crap!