I know this is a topic that could have a lot of causes but I'll try and debunk some before you suggest them. I have a 2006 HEMI QC 4wd with about 82k miles. It has a Revtek Front leveling kit, has 35" tires on 20" rims and a 3" body lift. I've had the tires for about 65k miles and they still have a good amount of tread left and look to be in good shape..I expect to get another 10k to 15k more miles out of them. I've had the tires rotated about every 10k and I have them balanced every now and then. Over the last several thousands miles I've been getting a shake in the truck at highway speeds. I don't really feel it in the steering wheel but I feel it in my whole body aka seat of my pants aka radar detector shakes etc. I've had the tires balanced a few times since and it doesn't make a different. Any thoughts as to what it could be? It's around 60-80 mph and in 2wd as I would never go over 40mph in my truck in 4wd. I have read that the IFS is bad about tie rods ends and ball joints especially when I commit the mortal sin of a leveling kit and 35's. I don't mind working on the truck myself and with some instructions or a haynes manual I don't mind getting dirty. What I do need is suggestions and how to check those suggestions as to the cause.

 

You can usually feel tie rod ends, wheel bearings and the rack more so in the steering wheel where ball joints feel more like what you describe, but I say USUALLY. So I'd get the front end up and start shaking sh*t until I felt play in something, starting with the ball joints.

Also, don't discount just plain old tire wear, I've had some tires start to cause vibration issues despite the wear looked to be even and natural but get down around 25-35% tread left...

 

What kind of balance do you have on the rims and tires? Could it be possible that you lost a weight off them, throwing the balance off?

 

Don't think I've lost a weight as having them balanced multiple times has had no effect on it. Any easy way to check the ball joints? I believe those are what people on here say wear out premature and can be replaced with a greasable aftermarket one?

 

Jack up the wheel hub assembly right inside the inner edge of the tire to take the weight off. Grab the bottom of the tire and pull up, or put an ex handle or 2x4 under it and pull up, it helps to have an extra set of eyes. You're looking for play on the ball joints themselves.

There's a diy here on ball joints. Just did mine. You really need a strong impac gun and a big socket (1 1/8" i think) for the cv spline bolt. You'll also need a ball joint press kit (you can rent or borrow from part stores) and a big a** ball peen hammer.

If you install greasable bj's(you're crazy if you don't) install the zert fittings on the bj's BEFORE you bolt everything back up, and be careful not to break em' off when you tighten the main bolt back on the cv.

About the shaking, another thing to check is the rear drive shaft. Get under the truck and shake both ends for play, ds's are balanced but the u-joints can go bad on you.

On one of my trucks I swapped the rear wheels for the front but kept each wheel on the original side, took it for a ride and the shaking was now in the front, culprit- FAILING tire integrity.

 

I agree with hammer bout the tread wear I had mud tires on my Dakota and if you looked at them good the front of the lugs were taller than the back I could have them balanced every time I drove it and the while truck still shook

 

Like hammer said Its more likely you have bad lower balljoints. Lift kits generally strains them. But other things to look at are these if your ball joints are good.

1. Check for flatspotting on your tires. Usually on bigger tires if you ever lock the brakes up you'll get flat spots. This should be caught by the guy rotating your tires.

2. Usually U-joints make noise, but sometimes an over compensation (over 30*) from trans to axle can make for some bad vibrations when there worn out. Assuming you raised your frame further away from the pumkin this is a good place to check as well, any up/down/side to side play is no good. While there check the drive shaft most of the time if you feel a lump where something was welded to it, you may have an out of balance drive shaft.

3. you could have a warped rotor as well, those big tires have more mass and will make your brakes much hotter, this to me makes sense since your driving way to fast with them big @ss tires!

4. Iv'e never seen a steel 20" rim that wasn't a spare tire. Is your shop using a torque stick when zipping them mega expensive rims back on? Allot of people don't know but over torquing aluminum will warp the rim!

5. You may be out of alignment as well, it's probably been checked but you have allot of friction up in the nose of that beast now. It'll take smaller bumps to knock it out.

These are the most common problem's i can recommend looking for.

 

So I took the truck to the tire place near my house for them to check it out. They are a good bunch of people and always steer you in the right direction even if it means they won't make any money off of you. They said Tie Rods and Ball Joints look great and everything else seems fine. They found some flat spots on the tires and drove the truck and felt the shake (although they didn't think it was as big of a deal as I do) and said they believe it's the flat spots on the tires causing them. Since I still have some good tread on them their suggestion was live with it and get another 10k to 15k miles more out of the tires. I think I will take their advice lol. I now have 70,000 miles on my tires (Yes, 70 thousand!!!) and still have at least 1/4 inch of tread left. I'm pissed that Cooper doesn't make a 37inch Discoverer STT cause I'd put those on in a heartbeat but I'm kinda wanting some 37s. Guess that's a decision I won't have to make for another 15,000 miles.

 

You think you've got vibrations now, put you those 37s on an IFS, coil-over front end... Just a word of warning cause if you think what you got now is a bigger deal then the shop guys do, you'll be going nuts with 37s. Plus I'd suggest you pick up a spare CV axle and if you don't already know how to swap one, you prolly need to learn...

 

Yeah I heard it's bad to go that big on the IFS but even my wife says I need bigger tires lol. I've replaced a CV joint on a Front wheel drive toyota so I would guess it's the same concept. What else wears out on the front end with bigger tires? I just had the tie rods and ball joints checked and was told those were in good shape. The tires wouldn't be coming for anther year and 12k miles so I'll have everything checked again when I get the 37s.