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The Hunting 2011

KevinGo

Full Member
Joined
Nov 1, 2019
Messages
11
My LTZ will not drive a straight line at freeway speeds without almost constant driver input. It's been aligned by a guy with a great reputation, and he did not see any excessive wear although he pointed out the mileage (110k) on the truck and said his experience tells him one or both front shocks will be done in another 10k or so miles, but they aren't leaking now.

I thought it might be the big steel bumper I hung on the rear end shifting the weight balance too far back, but loading the front portion of the bed with 200lbs worth of scuba tanks made no difference.

It has stock sized Bridgestones on it, three are same mileage while one (on rear axle) is a fairly recent replacement for a sidewall damaged tire. I have not experimented with pressures I run around 31psig cold, and get even wear patterns

Final thought, at freeway speeds if I hit a bump (think extra tall expansion joint) the right front gives a bit of a shudder. It settles out on it's own, but the left side hits that bump and remains solid as a rock. Is something worn on the right front and my guy, in spite of his rep, missed it? Nobody is perfect?
 
I would suspect your worn out bushings. Mine had new tie rods, ball joints and everything but shocks which I did myself. Best to replace it all both sides, instead of chasing. I also had a wheel alignment done at a shop with high tech alignment. Gives before and after print-out. I think it was only $100 job. Mine showed toe-in was a bit off and too much negative camber. /--\. Check the control arm bushings too, could be your problem. On my list. Good luck.
 
Is the entire front end original or has it been reworked at some point? Tie rod ends, ball joints, control arm bushings, and shocks are all well-worn at 110,000+ miles. If it were me, I'd replace inner & outer tie rod ends and lower ball joint on both sides and get another alignment and go from there.. If you're feeling rich go ahead and do the shocks too, but I don't think that's your main issue although it may be contributory. I hate changing parts just to see if it fixes something, but at the age & mileage of your setup it's likely time anyway.
 
The front end is completely original. After I posted I thought of the tie rod ends, and I hadn’t thought about the bushings at all. I’ll probably hold off the shocks for now. My alignment guy has been in the business for thirty years and is very good, but as a human is not infallible.
When I get back home I’ll get it in for another look, maybe a second opinion aka another shop. Thanks for the input!
 
I finally got home and back to the truck earlier this month. I took the Avalanche in, prepared for a finding of worn parts.
Alignment, all they did.

I was skeptical but took her for a spin and no hunting on the freeway. Bumps no longer upset the right front, and the previous crashing sounds of protest over said bumps are gone. Weird. But I'll take it for now and if anything crops up in the coming months, I'll look at going through the front end this summer.
 
I finally got home and back to the truck earlier this month. I took the Avalanche in, prepared for a finding of worn parts.
Alignment, all they did.

I was skeptical but took her for a spin and no hunting on the freeway. Bumps no longer upset the right front, and the previous crashing sounds of protest over said bumps are gone. Weird. But I'll take it for now and if anything crops up in the coming months, I'll look at going through the front end this summer.
When one of my front shocks went bad (both times over the 262K miles I had Old Blue), the side that went bad would do exactly as you describe over bumps at speeds above 45 MPH. Actually, there was a "sweet" spot that was between 45-57MPH and it would shutter and jump when hitting a bump. As the shock got worse, the shuttering became jumping of the wheel, until I slowed way down, it would jump so much that the front end felt like it was going to fall off.

The first time it happened it was same scenario as you, on a highway bridge joint.

When it first started it was inconsistent, then it start happening more often until it would always happen in that sweet spot speed. I thought it was ball joints or worn bushings but it was not, it was simply the shocks.

I replaced the shocks and never had the problem again until the next set went bad.

It's the damper on the shocks, it no longer dampens.

With 100K+ on the shocks, I can almost guarantee that they are bad.
 
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Thanks for that info. It's weird it stopped after an alignment, and as good as it feels and sounds I don't trust it. The truck is for occasional use, mostly weekends, but I'll drive it a few times over the coming week and see if the trouble crops up again, and yes at this mileage I think I will pencil new shocks into the budget for early spring.
 
When one of my front shocks went bad (both times over the 262K miles I had Old Blue), the side that went bad would do exactly as you describe over bumps at speeds above 45 MPH. Actually, there was a "sweet" spot that was between 45-57MPH and it would shutter and jump when hitting a bump. As the shock got worse, the shuttering became jumping of the wheel, until I slowed way down, it would jump so much that the front end felt like it was going to fall off.

When it first started it was inconsistent, then it start happening more often until it would always happen in that sweet spot speed. I thought it was ball joints or worn bushings but it was not, it was simply the shocks.

I replaced the shocks and never had the problem again until the next set went bad.

It's the damper on the shocks, it no longer dampens.

With 100K+ on the shocks, I can almost guarantee that they are bad.

Thanks for that info. It's weird it stopped after an alignment, and as good as it feels and sounds I don't trust it. The truck is for occasional use, mostly weekends, but I'll drive it a few times over the coming week and see if the trouble crops up again, and yes at this mileage I think I will pencil new shocks into the budget for early spring.
Cool, maybe you can do some "sweet spot" testing and see if it acts up in a certain speed range like mine did. Could be interesting to see.
 
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