Well, after about 14 hours of wrenching, swearing, and having dirt, grease, and rust fall in my eyes and cover every square inch of me several times over, it's done.
I've only done a short shakedown run to cycle the suspension some before torquing the spring eye bolts to their final spec.
Initial impressions? Well, I was too busy carefully listening for odd noises or feelings on that first ride to really notice. I will say it doesn't give the hard jarring effect over bumps like it did on the sagged out original springs.
It sits like a classic SUV should, IMO. Looks like it is ready for most anything a person will realistically throw at it. Not that it wasn't pretty capable before given the flat belly pan they have.
I measured the height at the rocker panel at each wheel opening before and after. If going from tired, stockers to these 2.5" springs, you'll gain exactly 4" in height from before.
The driver's side sits 1/4"-1/2" lower for some reason. I can't imagine the steering and brake stuff is that much more. I'd think the battery would offset it. Perhaps the transfer case adds enough driver's side ballast to cause it. My fuel tank is centered where the factory spare tire went, so that's not the issue.
About to take it back out in a few, and plan on driving it most of the week to get a solid impression.
*Edited after the celebratory date night drive-in diner trip with the wife (and mutt).
So, the positives are a firm ride that is noticeably improved over potholes, bumps, etc. I opted for the Bilsteins and they dampen the impacts nicely. It's still an archaic, leaf sprung suspension, so don't expect modern day crossover comfort. The bumps are there, but the harshness is dampened tremendously, and any rebound bouncing is gone now. It is firmer than what I would like (I kinda like a cushy, floaty feel), but I'll adapt. No increased drivetrain angle issues.
The only negative I've noticed so far is some very minor bump-steer on larger impacts like bridge/pavement transitions, railroad crossings, or larger than should be 'transitions' on repaved sections of road. Nothing drastic, but you do feel the steering wheel move a bit. I'm guessing the slightly increased angle from the pitman arm comes into play here.
I also notice some harsh resonance at crawl speeds in the driveway. Unsure if the transfer case is making contact with the floor pan again, or just some harshness resonating through the driveshaft due to the suspension cycling on the very uneven driveway we have. Again, not noticed during any road driving, so not really concerning. front brake lines look to be plenty long in stock form during full droop/full turn testing in the shop. The rear brake line just does max out at full droop. It is also very ragged looking, so I will probably replace it with the 20" rear line for the 131" wheel base 79 J-10 to prevent any issues in the future. I need to go through the rear brakes anyway.
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