Tire guy said my ball joints are bad. The old tires were evenly worn. 2000 Blazer with 86,000 miles. Years ago as a mechanic, the procedure I used to check ball joints was...

1. Jack up the vehicle.
2. Remove the tire.
3. With the vehicle jacked up, place a block in position under the lower control arm.
4. Slowly lower the jack that's holding up the vehicle, allowing the control arm to unload its spring tension against the block.
5. Rock the spindle top to bottom while you view the ball joints.
5. Experiment with different amounts of control arm unloading
6. Repeat step four.

The idea being that you are attempting to float the spindle between the ball joints by removing the spring tension. With a properly floating spindle, ball joint wear would be obvious. My upper ball joint seems rock solid. The lower ball joint seems to have a very small amount of play.

Is this still a valid test? And how much play is too much?

Thanks, raz

 

i usually jack up the truck by the lower control arm and grab the wheel at 12 and 6 and if i can rock it back and forth the ball joints ares bad, if it has play at 8 and 3 its a tie rod and if there is play at 10 and 4 its probably a wheel hub

 

for second gen blazers the checking procedure is as follows....

UPPER BALL JOINT CHECKING

1. Raise and support vehicle with jackstand under lower control arm, near lower ball joint. Ensure upper control arm bumper does not contact frame. Place dial indicator against lower part of wheel rim. Push in on bottom of tire while pulling outward at top. Read dial indicator, then reverse push/pull procedure.

2. If lateral (horizontal) deflection exceeds .125 (3.18 mm), replace ball joint. With ball joint disconnected from steering knuckle, try to rotate ball joint by finger pressure. If ball joint can be rotated by finger pressure , replace ball joint.


LOWER BALL JOINT CHECKING

Raise and support vehicle with jackstand under lower control arm, near lower ball joint. Place dial indicator on spindle hub. Pry wheel between lower control arm and outer race to measure vertical movement. Note: dial indicator reading. If reading exceeds .125 (3.18 mm), replace loose ball joint.

 

Thanks for the tip, Q!

My truck has been rattling when I hit bumps, and on the highway it keeps wandering left and right, so it's hard to keep it in the lane. I did the procedure you mentioned above, and I could visibly see the play in the tie rods when I rocked the wheels at 3 and 9. The ball joints (replaced year before last with Moogs) and wheel hubs seem to be fine.

Now that I know what the problem is, I have some questions:

1. Is it just a matter of tightening the bolts? If it needs to be replaced, how do I know?
2. If it breaks before I fix it, will I immediately lose steering and possibly crash out?
3. Is there a how-to? I have found a lot of threads about replacing wheel bearings and ball joints, but I'm having trouble finding information about tie rod replacement. My wife is pregnant, and I am paranoid about letting her drive my truck until this is fixed. Thanks for any help.

 

1. Is it just a matter of tightening the bolts? If it needs to be replaced, how do I know?

No, if their is movement in a tie rod it needs to be replaced. the nut that holds the tie rod on is a castle nut with a cotter pin through it so it wont loosen up. a tie rod end is just a ball and socket joint and after a while the socket getts worn if not regurally greased. But it could also be a idler arm or pitman arm, you should have someone else shake the wheel while you look under the truck (with the front skid plate removed) and that will tell you if any other parts are worn. Heres a vid of a bad tie rod ... http://www.youtube.com/watch?v=so0vL...eature=related

2. If it breaks before I fix it, will I immediately lose steering and possibly crash out?

YES!!! So be careful until you fix it. if the tie rod or ball joint breaks you will have no steering and that could flip the truck or worse. I personally wouldnt drive the truck over 40 mph is a ball joint or tie rod is extremely loose. GET IT FIXED!!!!

3. Is there a how-to? I have found a lot of threads about replacing wheel bearings and ball joints, but I'm having trouble finding information about tie rod replacement. My wife is pregnant, and I am paranoid about letting her drive my truck until this is fixed. Thanks for
any help.
here is a outter tie rod replacement, its on a saturn but the concept is pretty much the same ..
http://www.youtube.com/watch?v=ZpI6J_97VCc

good luck!

 

Ryan, thanks very much for the information. But after looking at your videos, I realized that's not the part that was moving. I removed the skid plate a long time ago, so it's pretty easy to see under my vehicle. The part that moves when I play with the wheels is closer to the center of the vehicle. I thought that was the tie rod, but I may be mistaken. It may be the idler arm. I will look in my Haynes manual to make sure. I will also come back later and post pix of exactly what's moving. I'm sorry you took the time to post those vids when it was the wrong thing.

EDIT:

Okay, it is indeed the right tie rod. The play seemed to be occurring where it connected to the steering assembly, not at the wheel:

And here is the tie rod end, at the wheel (the wetness is because I had just driven through a puddle):

 

the first pic would be the inner tie rod, basicly the same as replacing the outter one. It only took me a couple of minutes to find those videos, dont worry about it.

 

Okay, thanks! BTW, Syracuse is a pretty cool town. I know a few people that live up there.

 

yea, its not too bad up here. Worst part is the roads and potholes that tear up my truck