So I have had a vibration in my 2002 Chevy Blazer since I purchased the vehicle. I normally thought like someone else that it may have something to do with tires and suspension. So for the past four months I have spent close to $2000 trying to fix and isolate my issue. To no avail i recently did something I have been wanting to do for a while that seems to help and I'm wondering if I can get some technical insight to see if my feeling is correct. To give some insight as to what work I have already done I'll go ahead and list everything now and some may not be related entirely to vibration at all. I just want to list all the work I have currently done to my vehicle since my purchase earlier this year.

I have replaced all tires, all rotors, all break pads, both front end shock absorbers, both front end lower ball joints, both front end upper control arms that included ball joints, both front end wheel bearings, both front end sway bar links, both rear sway bar links, both driveline u-joints, water pump, fuel filter and have done countless front end alignments and tire balancing.

I honestly thought that there was nothing I could do no matter how much research I could do or parts replaced and I would have to wait for something to break before I could fix it. Well a couple days ago I had decided to do something I had planned to do already and that was change the transmission filter and tighten up some bolts that may have lossened over time in the transmission like I had seen in Chris Fix's video on how to change transmission fluid and filter. So I followed his video exactly and everything went really well. Since I have changed my transmission filter, tightened those loose bolts and put in new fluid my drive is almost as smooth as glass with only minor hiccups here and there but it's still like night and day when compared to how it was.

So my question is did this really help my vibration issue and why would it if it did?

 

I'm wondering if it was a friday build, and the assembler didnt double check before sending the truck off the line. Maybe worn bushings and such, depending on what you have tightened, it couldve just been something nicked loose. At the beginning I was thinking that there could be a shot LCA bushing that has been worked out... I think that was the only thing not mentioned in the front end work.

 

The lower control arm bushing was fine and didn't need replacing. I only tightened the bolts that were on the transmission itself that we're covered by the transmission filter and pan itself. I'm just wondering why would my vibration disappeare after doing that.

 

While under the truck could you have moved something such as a heat shield that might have been vibrating to a position in which it stopped?

 

There wasn't a heat shield that I had noticed. It was just removing the pan for trannt fluid, replacing tranny filter and tightening bolts that were only accessible by removing both pan and filter. I did also have to replace the fluid with new fluid if that helps.

 

Hmmm. I keep trying to think of things that have rattled on my cars. The only other one I can think of is if you had something loose in your catalytic converter. Mine rattled quite a bit before I replaced it. But I'm at a loss for how even just knocking the cat could cause it even temporarily stop ratting if the innards were already loose.

 

No I mean my entire vehicle would vibrate. Like around 60-75 would be the worst.

 

Hmmm. Who knows maybe a fluid leak in the valve body between it and trans causing a clutch chatter. Hope that fixes your prob for good.

 

Yikes! Yes that is crazy bad. I wouldn't be surprised if the issue was the fluid pick-up through the filter. Perhaps air was getting in disrupting the supply of fluid to the rest of the transmission?