Sorry it's been a bit longer on the update, we've had sucky weather hear for a while. Got a break yesterday in the weather and was able to get the shocks and springs installed. I was in a rush to get them on that I forgot to take any ride height measurements.
Just from eyeballing the truck, I do think it lost probably 1-1/2" in rear ride height. It used to sit with a pronounced "stink bug" stance in the rear and it's closer to level now, not dead level just closer. I'll measure the fender heights on it next time I have it in the garage which will hopefully be sooner rather than later. Maybe the 3/4-ton springs would have kept rear ride height closer (?) but they may also have been too stiff spring rate as well (?). I'd like to have a set to try them back to back, but oh well.
The RH front shock (which was a Bilstein 4600 was a major PITA to get off. The threads on the shock stud had rusted up...I am guessing from condensation dripping on it from the AC lines running above it, as the shocks haven't been on the truck *that* long and the LH side was fine. Soaked it in Liquid Wrench, put heat from a propane torch on it - nothing. I ended up cutting the nut off with a dremel and cut-off wheel. When I put the new shocks on, I cut a rubber fuel line (vacuum line would work) the length of the stud and dabbed a little gob of Bel-Ray Waterproof Grease (used on dirtbikes) in the end of the line and slid it down over the stud - they'll come off easy the next time.
One note - the 5100 series shocks have rubber boots covering the shock shaft and since the shock I got was for 0-2.5" lift, I was afraid it was too long when I first put it in place because the rubber boot was VERY bunched up. I pulled the shock off and removed the boot and put the shock back on the truck so I could see the shock shaft and there was 2" of shaft available - this was with the truck sitting on the ground at rest - no jack or anything "lifting" it, and this Yukon sits low IMO. So, satisfied that the 0-2.5" shocks were gonna work just fine, I pulled the shock back off and put the boot back on it - pulling the bottom of the boot down the shock body as far as it would go. Once I got the shocks bolted in place, I went back and slid the boots up about 1/2" where I wanted them and put new zip-ties on them.
Now for the ride report......the truck rides SO MUCH better now. It is best described as "firm, but supple". The 5100 series shocks are valved so much better than the 4600 IMO, I run these on my truck as well (2500HD). I went on a 30min test ride out on a country backroad that we travel a lot, the road has bumps, lots of dips, curves and camber of the road going from side to side and also took a short run down the interstate and back. Body roll is improved and body sway is much improved. Hitting dips at speed, the truck didn't bounce a few times like it used to, it now takes a bounce and settles right back down. Hitting bumps and expantion joints are soaked up nice as well - you know you hit a bump but it's not a hard jar rattle.
I am REALLY REALLY pleased with the ride improvement. Now, maybe the Nivomats were just that far gone, I don't know and anytime you get new tires or shocks it seems like night and day difference, but I don't remember the truck ever riding as good as it does now - and we bought it at 36,000 miles and it now has 133,000 miles. Overall, I am VERY pleased with the results.
I think I have rear height measurements to the trailer hitch from when I was working on another project. I'll try and dig that up and if so, I'll check that height now and post up the difference.
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