Vacuum:

I'm just wondering if it matters material or size vacuum line i use to replace any cracked line i have?

c/v axle:

I will now assume that my cv axle is shot. I have a humming/vibration that comes from the front passenger side. I have done upper and lower ball joints, upper control arms and bushing, idler arm, drivers side tie rod, and hubs(twice, once 3 months ago, and first time about 7 months)

only modifications are 2" add a leaf kit on rear and torsion tightening to level.

 

The same size and material would be best for replacing the vacuum lines. That being said if you use anything else that is tight enough to seal air tight and survive the extreme temperature changes, why not.
The CV joint should be obvious if you jack up that wheel and rotate it back and forth. Sometimes the boot is also shot and leaking.

You are learning why they don't come from the factory with the torsion bars raised all the way. It's rough on suspension components.
I'm running 31-10.50-15 Goodyear Duratracs on my 99 w/o any lift. Needed to tap on the edge of the fenders just behind the front ones about an inch. That lower edge folds over neatly.
No rubs anywhere anytime with stock wheels.

 

Here is the thread I started to report on my under-hood vacuum line replacement: https://blazerforum.com/forum/2nd-ge...replace-95425/

 

Thanks for the feedback

 

Hey DonL,
Mainly, when CV is shot, the vibrations are constant while driving and significantly increase whenever wheels are turned hard. You've done lots of repairs, did You notice the condition of a CV axle boot? Was it perforated with grease leaking outside...? I'm afraid Your diagnosis is most probably correct, but - at last - did You check the wheel balance?
I remember a time, when I went for the geometry cause of extensive vibrations. Staff asked me if I just plow a field with my ride - there was a lot of mud/clay on the rims on the inner side (rainy days on my village roads). Then I had meet my neighbor who started the story with "You know... Last days I went for the geometry because of vibrations..." I had interrupted him and went to the point
Other story is You may have a tire out of balance after a sudden, heavy braking. That had happened to me too.
Cheers,
Mike

 

I went underneath today and checked, boot is solid but not connected to the inner end... barely to none grease. Going in tomorrow to load it up and make sure there's no debree or shavings. What kind of grease would be best?

 

What exactly You mean by an "unconnected boot on the inner end"? I am confused here. Axle has two boots (inner/outer) and each of boots is fixed by a steel clamp on either end. I've just finished replacing my CV boots today - I used sets from EMPI - they are delivered with a small sack of grease, so I cannot say an exact kind of grease.

 

The passenger cv axle, the bigger boot on the engine side, the tie that came with it came off... so the boot slipped towards the tire exposing the inner knuckle. So I gotta re pack it and tie it back so it doesn't come off again

 

I had the inner end of the passenger side inner CV boot come off. I was able to re-secure it with a hose clamp. Just be mindful when you put it on to do it so that when you tighten the screw on the clamp, the torque of the screw driver doesn't twist the clamp so that it slips to the inside (toward the center of the truck).

Because I did a torsion bar crank as part of a suspension lift, to get the angle correct and be able to to slip the boot back on, I had to remove the tension on the torsion bar. After I got it on, I readjusted the torsion bar.

It has stayed on for several months now and survived hundreds of miles of city and highway driving along with slow driving on some un-maintained skid-roads in the woods. (I just now checked it to be sure. )

 

Christine, did u reapply any grease?