4x4 problem solved

[Pitch22]

I posted on here a couple of months ago telling you guys about the problem with my 4wd. How it would rarely work after I got my 2.5'' lift put on. I tried everything to fix it but nothing made a difference at all. Finally I had no choice but to take the lift off. After all I would rather have 4wd than a lift. I took the lift off and although my TB looks low now, the 4wd works completely fine. Does anyone know why this could be?

[DustinC1989]

What kind of lift? I suspect a outside the strut lift..

[The Roadie]

Did you troubleshoot it using the flowchart provided on the site? Taking off the lift is not any part of a proper troubleshooting process.

I'd guess a borked splined disconnect with bad bearings that allowed a lifted CV shaft to tilt the gears and the collar couldn't slide anymore.

A simple lift install (not one of the criminally-designed outside the strut monsters) would not damage a good disconnect. A bad lift could, and your bearings and seals might be bad even now and it's a ticking time bomb waiting to fail.

But you said you tried everything to fix it, so you must have put on a new disconnect. Hmmmm, so now I can't guess what's up.

[DustinC1989]

(not one of the criminally-designed outside the strut monsters.

That's my guess, eBay vendors are really pushing those kits lately and I suspect he may have fallen victim.
Will have to wait for him to verify though

[Pitch22]

The lift was just a 2.5" scpacer that attaches to the top of the strut that I got off ebay. Is the problem because of the cheap spacer? Or is there something wrong (or going bad) with my truck like the disconnect, shaft, etc.? If I got a similar but higher quality lift would it work or would the problem still be here?

[DustinC1989]

Bingo, eBay lift was your problem.
Anything that attaches to the top of your strut is a outside the stut spacer.

A MarkMC lift will not have that problem and probably doesn't cost much more than the eBay kit you purchased.
http://theliftmeister.com/public_html/t ... ister.com/

EDIT:
I will also add that the absolute maximum for outside the strut is 1/2"
Marks 2.5" kit has a spacer that preloads the spring and goes UNDER the strut top plate, therefore is inside the strut assembly and has a 1/2" plate for the top of the top plate.

His 3" lift completely replaces the factory strut top mount (which is rather weak)
So it is the strut mount and lift all in one

[The Roadie]

1) The Ebay criminal's lift may have damaged the bearings and seal of your splined disconnect. There's no way for the inside of the disconnect to be affected by anything outside the disconnect except if the CV shaft sends stress past the bearings to it.

2) The CV shaft inside joints have been overstressed. May need new CV shafts.

3) The driver's side bearing and seal on the differential may also be damaged for the same reason as item #1.

4) The risks of damage that might break things on a trail are why these vendors need to be shunned.

[Pitch22]

I only ran with this ebay lift for about 2 months, maybe a little more. Do you think this caused any permanent damage? And if I get a MarkMC lift, the same problems wont appear? Thanks everyone for your replies. I appreciate it.

[DustinC1989]

No, Mark's kits lift the vehicle, but down travel is still limited

[Trail X]

It may have caused permanent damage. The biggest risk areas are your tripod joints (but they are pretty tough as long as the boots don't rip), and the front diff and front disco outer bearings and seals.

[Pitch22]

Would any of these problems cause a humming noise/vibration starting at about 35mph? I'm pretty sure it's a wheel bearing. I'm asking just to make sure.

[DustinC1989]

If the CV joints are bad it can also cause noise and vibration.
With the lift you were running, that would be something I'd look into first.

Look up Detroit Axle, you can get both CV axles and both front bearings for about the same price as one duralast wheel bearing...

[TBYODA]

Look up Detroit Axle, you can get both CV axles and both front bearings for about the same price as one duralast wheel bearing...

Here you go, I have made it point as I read threads to save these little goodies like this. In this case I forgot to and had to ping HARDTRAILZ but he was very helpful and stated he has had good luck these.

Detroit Axle Main Page
AM Autoparts Chevy Trailblazer Parts
CV axle
WHEEL HUB

[The Roadie]

I only ran with this ebay lift for about 2 months, maybe a little more. Do you think this caused any permanent damage?

You can get permanent damage in the first HOUR after installing a strut-lengthening kit.

And if I get a MarkMC lift, the same problems wont appear?

Mark's and all other legitimate kits don't lengthen the strut. It's the longer strut that allows the suspension to get OVER-extended when it's unweighted. If you put on that sort of kit, and only drive it to the mall and never go over speed bumps quickly, you might be able to avoid over-extending your suspension.

But since there's never anything even close to a free lunch, the good kits just trade down-travel for up-travel. The total travel of the suspension is fixed by the shock's difference between its extended and compressed length. And a bit complicated by the fact that the strut isn't mounted at the outboard END of the lower control arm, but it's mounted about 2/3 of the way out. So the shock travel (if you measure it) has to be multiplied by 1.5 to get the travel at the wheel.

But let's say that's 10" up to down travel at the wheel, and the suspension as it came from the factory lets the vehicle sit at the half-way point - 5" up and 5" down-travel available from its resting height. A stiffer spring, or one that's been preloaded by a spacer installed on top of the compressed spring, doesn't change the shock in any way. It still will deliver 10" total stroke at the tire. But it's the RESTING height that's changed, let's say by +3". So now the vehicle sits 3" higher, but the suspension can now compress 8" when you slam down on the trail after going over a lump. And if you are traveling quickly over a whoopsie-doo lump, and go zero-G and unweight the suspension, the tire will only extend 2" from its resting height.

The bad kind of spacer, let's say a 2" spacer that makes the strut 2" longer but (because of the lever arm effect) makes the vehicle sit 3" taller, will give you a strut that overbends the CV joint, transfers stress to the bearings that touch the CV inner shafts, and puts the upper ball joint mounting shaft at risk, when you unweight the suspension after a bump.

[Pitch22]

Thanks guys. One more question, what are some signs of a bad cv? What are some easy ways to find out if it's bad?

[The Roadie]

Support the frame and fully extend the suspension. Rotate the tire and feel for any noise or resistance during the rotation.

Alternatively (my usual plan) - wheel it hard. See if it breaks. Have a spare and tools ready.

[Pitch22]

Thanks a lot guys.

[Pitch22]

So I supported the frame, fully extended the front suspension, and rotated the tires. The left tire seemed a little harder to turn than the right. The humming noise while driving seems to be coming from the left side also and the left wheel bearing was replaced roughly two months. Also I notice while driving if i turn to the right the noise gets quieter and when I turn to the left it gets louder. This is while driving above 45mph. Does this sound like a bad cv to you guys? If it is a bad cv, should I just replace the bad one or should I just go ahead and replace both axles since I would think the other axle is close to going bad too?

[DustinC1989]

Sounds like a bad wheel bearing

[The Roadie]

CVs don't change noise when turning left or right. Hub bearings do. What brand did you use?

Have you wiggled the inner tripot joint around to see if you can see any play at the differential or the splined disconnect that would indicate bearing or seal damage?