So, I'm going to install some new Arnotts in the front

[al2fast]

And I'm wondering what else I should consider replacing? I have an 09 YD with some 1" or so aluminum leveling blocks on the bottom of the shocks. Have around 116k on the clock.

I was crawling around under there and the boots on the tie rod ends look fine, not ripped or anything. The sway bar link bushings look fine too, again not cracked or busted up. The sway bar bushings that hold the bar to the frame also don't look like junk either, no cracks or visible deterioration.

I don't have clunking when I turn nor play in the wheel. I can only assume that all of the front end parts are original, I've only owned this since 75k miles and 3 years now and have never replaced anything suspension related on the front.

My only complaint about the ride is I get some minor vibration in the front at highway speeds. Was way worse with 33" KO2 on. So much it pissed me off to drive it on the highway so got rid of those for some Discoverer AT3 in factory 20" 275 55 which ride about as good as the 22" Bridgestone Alenza I had on prior to this wheel/tire setup. I guess I figure my 2010 work car Ford Escape is smooth at 75mph so should my Denali. I've spent more time at the tire shop with road force balancing, swapping tires...Same shop put tires on my wife's car last year and no issues, so I don't question their competency. Steering wheel doesn't vibrate left and right or anything with the vibrations. My factory electronic shocks are wet on the top, so I'm optimistic that new shocks will smoothen things out for me.

Any suggestions for the front end or just let it ride? I'm thinking about just doing the sway bar bushings and link bushings because they are cheap and I'm going to have to loosen that sway bar link to get the shocks out anyways...

Thanks.

 

[swathdiver]

Highway vibrations are almost always wheels and tires. Then worn shocks unable to dampen proper. And since nothing is loose and the tires are wearing even I'd go back to the tires.

Does the vibration settle down after a while as the tires heat up? I have LT tires on mine and now with the TPMS we can see more precisely the air pressures. Even after airing them all up the same early in the morning, after a week they are different. Fire up a cold truck and they vary by 5 psi and after about 30 minutes on the highway they're all warm and happy as clams at the same tire pressure, that is until the sun warms up one side more than the other! Same with sitting in the driveway, the east facing tires are different than the other side until late afternoon if it sits in the driveway all day.

Tire machines should be recalibrated periodically and most places never do this. Often times the tire has to be rotated on the wheel to get it balance out properly too. I used to be a tire guy.

 

[al2fast]

Highway vibrations are almost always wheels and tires. Then worn shocks unable to dampen proper. And since nothing is loose and the tires are wearing even I'd go back to the tires.

Does the vibration settle down after a while as the tires heat up? I have LT tires on mine and now with the TPMS we can see more precisely the air pressures. Even after airing them all up the same early in the morning, after a week they are different. Fire up a cold truck and they vary by 5 psi and after about 30 minutes on the highway they're all warm and happy as clams at the same tire pressure, that is until the sun warms up one side more than the other! Same with sitting in the driveway, the east facing tires are different than the other side until late afternoon if it sits in the driveway all day.

Tire machines should be recalibrated periodically and most places never do this. Often times the tire has to be rotated on the wheel to get it balance out properly too. I used to be a tire guy.

Thanks for the input, I was leaning towards the tires, my rims are 0 offset, not sure how much that messes with ride. Definitely don't see any tire related issues, I change my oil about 5k mile intervals and rotate my tires every oil change and the wear looks fine.

I get that cold tire vibration you speak of but it is gone by the time I get to the interstate, I have about a 4 mile drive to the interstate. I'll have to try and add some pressure to the tires and see how that affects the ride. I have them at 32psi cold on all 4 corners.

 

[iamdub]

Ex-tire guy here as well (Certified ). Shock absorbers do just that- absorb shock. They can't cause or "fix" a shake such as you describe. In some cases they can help hide a shake by absorbing it so it's not transmitted so much to the frame/body/driver, but that's not fixing it.

I agree with James. Bigger tires are more prone to getting out of balance so you switching to the smaller tires helped. Also, balancing can only go so far because you can balance a square, but that doesn't mean it will roll smoothly. Does the shaking change any when you rotate the tires? Have you had had the runout checked on every wheel? These are checks for a bent wheel(s). If the shaking seems to always be in the front, you may have a worn/damaged hub.

Air pressure plays a role, too. Mine developed a shake at 65+ MPH and I found one tire to be about 10 PSI low. Aired it up to match the others and the shake went away. A week later, the shake was back and I found that same tire to be low again. Maybe try bumping all of your tires up to 35-37 PSI? It may not be the ideal pressure for those particular tires on your rig, but you can run it temporarily as a test to rule out one variable.

 

[al2fast]

When I had the issues in the beginning the shop said they checked the runout on the rims and they were fine, they are 20x9 ProComp 31 Series wheels. This was when they found a tire out of spec and warrantied it (AT KO2 at the time). THey gave me a printout from the road force machine with all of their findings, I doubt I have that anymore. Yes, the vibration is always in the front, nothing changes regardless of what tire is in what position. I was never a "tire guy" but I took all of the car classes in high school (in the early 90's) and mounted and balanced tires. I do as much of my own work as possible. It feels like tires to me but I've had 3 different tire shops tell me no problems with balance & tires, "your truck has 100k miles it's not going to ride like its new anymore." I'll have to jack up the PSI and see if that helps. I've definitely had wheel bearings go out before, been a while but I distinctly remember that noise that gets louder and the vibration that gets worse as you go faster.

I know I'm picky but I guess where I'm going is it does have 115k, it's not new anymore, however I can replace the worn parts that are the culprits making it not ride like new so I'm trying to figure out what it is most likely. The vibration that I do feel does slightly change with road surface types so that makes me think the shocks because when I drive down a butter smooth section of interstate that they recently took that grinding machine to it sure rides smooth then. I noticed the back of my yukon definitely feels smoother with the new shocks so I think I'm running into analysis paralysis. I know my shocks are shot so I'll replace those and when I have the sway bar loosened I'll more closely inspect the sway bar end link bushings and determine if I should replace or not. The one thing my rig definitely doesn't do is any kind of clunking when turning or going over bumps.
Thanks for the input.

 

[al2fast]

Put the new Arnotts in the front. Had one of the bolts bust on the sway bar end link, so I got some Moogs from the local O'Reilley's so I could finish. They ride smoother for sure, bumps don't feel like I'm plowing over mini curbs anymore. Took it up 10 minutes on the interstate and it is smoother for sure. Wish it was a hair smoother, but have to be realistic about how smooth an A/T tire will ride at 80. The other vibrations I was feeling are gone for sure.

Not sure how good new stock shocks would ride vs these but I'm happy for sure with these Arnotts. I had about 117k on the clock when this was done.