vibration at idle/in drive

[sunliner]

2006 Trailblazer LS with 119,000 miles.
have a vibration that I started noticing a few weeks ago...seems to have gotten worse lately.not sure if the cooler weather has anything to do with it or just coincidental.
Vibration is at idle with the trans in Drive. goes away in all other gears and the truck drives fine. Seems to get better on longer drives as it warms up.
I have an ongoing issue with a lean condition (been discussed quite a bit elsewhere on the forum) but I don't know if this is related. Maybe motor mounts or driveline?

 

[littleblazer]

Most definitely motor mounts I would say. Eventually it'll take longer to go away. But it won't do it in the summer unless it gets really bad.

 

[sunliner]

Thanks! as a follow on question...according to the Haynes book...I'd have to remove the fan to get the engine up to replace the mounts. I've seen elsewhere that if you just loosen both mounts, replace one at a time so the engine kind of pivots up on the other mount, you can avoid having to screw with the fan. Anyone have any experience with this? I hate messing with the fan....

 

[Blckshdw]

I thought I read somewhere that you can disconnect the fan shroud from the radiator, that way the fan can move up/down along with the engine when lifted/lowered. That could be an option for you.

 

[sunliner]

Yep...I can't imagine why that would not work. Gonna find out this weekend...thanks

 

[6716]

Motor mounts aren't too bad. If you loosen the fan shroud you're in good shape there. It's not hard, per se, but I felt like I was making out with the strut the way I had to hug the thing to get both hands in there and make the swap. That's as dirty as I've been in all the work I've done on the truck was the motor mounts.

 

[kkeo211]

Not an extremely hard job to do but you will needs lots of extensions and some patience. I did the job about a year and a half ago due to the same type of noise you are describing. It took about 4 hours total (I lost a bolt and had to go buy a new one). Make sure you get mounts from the dealer and not aftermarket.

 

[sunliner]

.... but I felt like I was making out with the strut the way I had to hug the thing to get both hands in there and make the swap. That's as dirty as I've been in all the work I've done on the truck was the motor mounts.

I've never made out with this truck, but I've definitely talked dirty to it...

 

[gmcman]

Good thing is you have 2WD, I don't think I removed or loosened the fan shroud but it would definitely help.

I loosened the top bolt of one side, then took a block of wood on a floor jack and raised the block near the oil pan on the other side.... loosening the opposite side bolt let the engine pivot easier...just take it to where the intake just contacts the cowl but be careful as its plastic.

 

[Jon Blaze]

Im having the same problem
06 trailblazer 4/4 i6 76000 miles
In park and neutral same vibration no better or worse put in drive still there
Put in reverse and it goes away
I own 2 of the same vehicles same year same model just different mileage no problems with the other one. I checked the movement on both trucks and they seem the same. I mean engine movement with someone in it shifting gears and rev up in gear. Didnt know if i should start a new thread or just chime in.
Thank you

 

[webdawg]

Im having the same problem
06 trailblazer 4/4 i6 76000 miles
In park and neutral same vibration no better or worse put in drive still there
Put in reverse and it goes away
I own 2 of the same vehicles same year same model just different mileage no problems with the other one. I checked the movement on both trucks and they seem the same. I mean engine movement with someone in it shifting gears and rev up in gear. Didnt know if i should start a new thread or just chime in.
Thank you

Erratic idle at all?

 

[Jon Blaze]

No none
I just replaced plugs ac delco and also replaced all 6 coil packs with ac delco then cleaned tb and pulled both fuses before I started any work on it.

 

[webdawg]

Does it sound like a diesel engine? Check the camshaft actuator solenoid?

 

[Trace Roro]

Did you get those OEM motor mounts in? Did it fix your problem?

I too have low idle vibrations. I put aftermarket motor mounts on and have since ordered OEM ones. I checked my compression and it is good. While I'm waiting on the motor mounts I'm going to check my fuel pressure and injectors this weekend. I also replaced the exhaust VVT solenoid. This vibration is driving me crazy!!!

 

[Mooseman]

It is well known here that aftermarket mounts are not as good as OEM. Apparently not true hydraulic.

 

[Sparky]

I seem to recall someone found an aftermarket brand that actually worked decently after they did a redesign, but I cannot for the life of me remember which one it is.

Easier to just stick with OEM and not worry about it!