Usually I don't keep a vehicle long enough to need shocks, and any performance upgrades I ever did usually amounted to surfing a forum and reading someone else's recommendation. This time, I have 97k miles and 25 years on factory shocks and I noticed one has started leaking and none of them seem to be damping much anymore.
I need shocks for my truck. There is zero need for handling. It's a 4x4 with tall tires. It won't ever be a great slalom performer. I thought this would be a good opportunity to say "what type of damping do I need and why," Instead of "what shocks should I get for my truck." I'll learn more that way.
What I do want is a softer ride and still be able to control things with a 3500-lb trailer that has about 450 lbs tongue weight. Bonus for ideas that give a nod toward possible ride quality mods in the future; specifically, taking out a couple leaves of the rear spring and adding airbags for adjustable load control.
If bilstein makes a 5100 kit for your truck, that’s what I’d recommend. The digressive damping is great for having a smooth ride on the highway while having more damping for bigger bumps and keeping big tires under control.
The flex disc digressive piston closes some passages at high travel rates so it’s firm when needed and softer when needed.
In reply to Strizzo :
I have a set for my Sierra. That’s after many hours of research mind you. I haven’t bolted them in yet so I can’t off an opinion but I can say that I came to the same conclusion after LOTS of reading.
According to Bilstein and Tire Rack, no 5100 for Ranger/Mazda B-trucks except for one application for fronts that have been lifted 4-5"
Edit: I lied. I found a stock height for rear only. Fronts just for lifted trucks.
FWIW, I absolutely hate digressive shock valving. It ends up feeling needlessly harsh on small bumps and then when you hit a big one, it just blows right through all of the travel and slams the bumpstops.
Hmmm... if I knew more about the science behind it...
Divergent valving means higher damping for slower inputs, right? Then bigger velocities blow open a bigger valve?
FOA or Doetsch shocks can be found in the application you are looking for, around $150 per corner.
Are there concerns I should be thinking about with the ratio of compression to rebound damping? I know that different types of applications need different damping in each direction; for instance in drag racing they often use 80/20 or 90/10 so the front lifts ASAP for weight transfer and traction, then have plenty of compression damping for when the front comes down.
Is that something I should be considering as well?
How much damping and in what ratio would be affected by how stiff your springs are in addition to sprung and unsprung weight on each corner. If you're running stock springs, something similar to stock will probably be fine unless you've got things you want to change about how the suspension behaves.
Here's a good chart for off the shelf shock valving option.
I don't find that Bilstein chart all that accurate personally, especially outside of stock springs. They tend to use 255/70 as their default "SUV with coil springs" valving, yet with the springs I've got in my Jeep I'm running 400/100 and they're not over-damped. And I'm using 7100s like that chart is meant for.
rslifkin said:
How much damping and in what ratio would be affected by how stiff your springs are in addition to sprung and unsprung weight on each corner. If you're running stock springs, something similar to stock will probably be fine unless you've got things you want to change about how the suspension behaves.
No idea what the spring rates are. Lot's of unsprung weight with 265/75-16s on factory aluminum rims. It's also a double I-beam Ford setup on torsion bars, so lots of fulcrum-y axle weight.
The only thing I would want to change is to improve ride quality. I don't mind crappy handling (which I have already) and a floaty-squishy ride, but I'm trying to choose one that won't make me clash my teeth when I run over a dead leaf.
I realize that my spring rate may be responsible for much of that, and the current ride isn't horrible... I just don't want to fall into the trap of buying more expensive shocks only to find out they are designed for high performance handling and I end up making things worse. I also don't want to go underdamped and make towing a trailer or hauling lumber a big floppy nightmare. Truth be told, (especially if I go with airbags/fewer leaves) I wouldn't mind it being a little underdamped if it helps ride quality because 90% of the time it's either empty of has some little stuff in it. Maybe once a month it tows or has a lot of payload in it.
The long term goal for it may include some spring softening with auxiliary help, like possibly ditching a few leaves from the rear and adding airbags, or swapping the front torsion bars for ones from a 4-cyl model and re-setting height with adjustable keys (haven't researched that yet, just spitballing.)
The problem I have with any truck is that they shoot for the middle, so they're stiff and bouncy empty and squishy and soft at GVWR. Today I had about 450 lbs in the bed and it was perfect. :) Hopefully adding airbags/ditching leaves in the back will make it adjustable for a bit of both. Thanks to IanF, I have a York compressor for some onboard air if I can make it fit.
