humming noise r/f

[Glenn Peters]

Hey just picked up my blaze from the body shop no the drive home the noise returned and its snowing so I said to my self time to play. Popped it into 4WD and noise gone, back into 2WD, a couple minutes later it came back,back into 4WD noise gone, back into 2WD noise gone. Slowed to about 30 mph noise kind of went away, back up to 50+ mph and all of a sudden the noise is back. Noise also changes as the R/F suspesion travels through its stroke. All noises are caused by vibration, I'm begining to wonder if the R/F shaft or R/F axle bearing is where the problem lies. This weekend I'm going to run it with chassis ears to try to pin point closer to the cause. I'll let ya all know. Till then turn up the radio!

[Jdizil]

Rocky Z that sounds right. Yes the sound does get louder as I speed up the wierd thing is when your in the car it sounds louder on the passeger side then the driver side.
Glenn Peters-I tried to switch it into 4wd hi and the sound goes away when I first engage it and then it comes back full strength.

[Jdizil]

THANK GOD!!!!!!!!!!!!!!!!I took my blazer in to adjust my torsion bar to level out my car and they noticed that my "Right front hub assembly" was shot and I needed a new idler arm. After replacement, the car runs smooth. Now this worked for my situation good luck. By the way, it cost me $645 to get it fixed but it was worth it for my sanity.

[Glenn Peters]

I replaced mine, wheel bearing that is. Not the problem. Glad to hear your problem is solved.

[new2blazers]

Sounds like there are a couple of different issues with all these vehicles. Some are the hub/bearing, and others sound more like vac/ electrical issues. I recently took my 99 Blazer on a road trip to Kansas City. (325 miles) Before then, I had only experienced the noise once. On the trip after about 50 miles, it started making the noise at 75 mph in 2wd. As I let off the accelerator, the noise got louder, and when speeding up it quieted. I slowed to 60mph and switched to 4hi and the noise immediately went away. Back to 2wd and it started right back. So I switched to 4hi and drove for 4 or 5 miles and switched back to 2wd. This time I noticed a noticable clunk as it switched back to 2wd. I had no more noise the rest of the way up there or back. Upon getting home, just for kicks I put it in 4wd for a little off road. As soon as I got back on the highway and put it in 2wd, the noise came back. Switched to 4wd for 4 or 5 miles, back to 2wd (noticable clunk again) and no noise for the last week. I think mine is the issue with the vac/switch sticking. I am going to try that when I get some days off. Sorry so long winded, but this is just my experience with this annoying problem.

[RockyZ]

Originally Posted by new2blazers

Sounds like there are a couple of different issues with all these vehicles. Some are the hub/bearing, and others sound more like vac/ electrical issues. I recently took my 99 Blazer on a road trip to Kansas City. (325 miles) Before then, I had only experienced the noise once. On the trip after about 50 miles, it started making the noise at 75 mph in 2wd. As I let off the accelerator, the noise got louder, and when speeding up it quieted. I slowed to 60mph and switched to 4hi and the noise immediately went away. Back to 2wd and it started right back. So I switched to 4hi and drove for 4 or 5 miles and switched back to 2wd. This time I noticed a noticable clunk as it switched back to 2wd. I had no more noise the rest of the way up there or back. Upon getting home, just for kicks I put it in 4wd for a little off road. As soon as I got back on the highway and put it in 2wd, the noise came back. Switched to 4wd for 4 or 5 miles, back to 2wd (noticable clunk again) and no noise for the last week. I think mine is the issue with the vac/switch sticking. I am going to try that when I get some days off. Sorry so long winded, but this is just my experience with this annoying problem.

Hey, I think you are on to something. I believe that maybe at the higher speeds the actuater is moving the front drive axle out of 4wd a little farther than when at slow speeds. My 2000 blazer has the exact same problem and when it gets real noisey and obnoxious I switch to 4wd and back out at a higher speed and it makes a difference but doesn't eliminate it. I haven't tried it at 60mph because when I look at the front axle it reminds me of the one on my garden tractor(not big enough for the job). I am going to put synthetic fluid in mind as soon as it warms up a little and see if it helps. If you find out the anser please let me know and I will do the same.

[Jimmy95]

Hi Guys
I have a problem with my Jimmy NOT going out of 4wheel, it wont go into 2w or 4 low either. When the engine is off and I press the botton with the key turned on, I hear a electrical motor sound coming from the transfer case. When button pressed on dash, it just flashes on 2w and goes back to the 4w drive. What do you think the problem is?

[88S10Blazer]

wow must be alotta people are having 4X4 problems, well mine just dosen't like go in to 4x4 i usally have to wait an reverse foward, then it finally kicks in

[KARLM]

Mine too. Loud tire sound during acceleration quiets when coasting. Noise changes as I ride over highway mounds. 1998 4.3 Blazer.


QUOTE=Jdizil]I have a 98 Blazer and it also makes a loud humming noise and as I speed up it gets louder. I tried switching it over to 4wd hi it worked for a second but then it gets louder. When I hit bumps on the road it goes away but then returns when I get back on flat land. Anyone have any ideas what it could be?[/quote]

[frankjc]

mine still does it intermittantly.
it seems like if i switch in and out of 4wd, it goes away.
i recently raplaced ball joints, idler, and pitman arms, they were all worn, and had nothing to do with the noise i guess.

[Glenn Peters]

I have been thinking on this for months, just listening and trying different things. When you hear the noise you can feel a vibration. Put into 4wd the noise goes away(for the most part). The noise doesn't always happen. Hmmmmmmm. I replaced the ball joints in my Blazer, the noise is some what worse. The noise now changes pitch during suspension travel(some one had posted that theirs did that). I believe that the noise is a CV Joint on the right side, probably the inner. My noise doesn't change with steering input. Not sure when I will replace the axle shaft/cv joints. If some body wants to give it a shot on their ride, Let us all know how it turns out.

[Polaris101]

I have the same issue with my 2000 blazer. I also noticed when I turn to the right the noise goes away. When I turn to the left it is load as ever. These turns are done at 30+ mph on a sweeping corner. It is driving me nuts!! Thank goodness the stereo is good in this vehicle.

[Glenn Peters]

that sounds like you have a possible wheelbearing issue

[hfx_guy]

hi this may sound simple but check your tire pressure,or the tire itself for damage (broken belt) the other issue that we have is a worn c.v. axle assembly. good luck jj.

[frankjc]

nope, it's not a tire, in my case anyways. i rotated them , and made sure they were properly inflated. still the same.