95 Legacy (Rear Axle Thumping Noise)

[John-USN]

95 Legacy Wagon with 140K miles.

Recently, from a stop, when I depress the accelerator, occasionally there is a thumping noise...one or two thumps, and then it ceases. Sounds like it is coming from the rear axle, but, not sure.

Other than that, car runs like new. Any ideas on what might be causing the strange noises??

Thanks, John

 

[DS]

Loose exhaust? Check the obvious first. Crawl under and take a look.

DS

 

[John-USN]

I did....I forgot to mention that I was under there today, fixing the heat shield/flex coupling by the rear catalatic convertor.

Other than rust, the rear is together solid....nothing loose. And the sound only occurs, occasionally, from the stopped position...not while I am driving, and not everytime.

John

 

[AS]

Did you have a flat tired fixed?

I did....I forgot to mention that I was under there today, fixing the heat shield/flex coupling by the rear catalatic convertor.

Other than rust, the rear is together solid....nothing loose. And the sound only occurs, occasionally, from the stopped position...not while I am driving, and not everytime.

John

 

[John-USN]

No, I didn't....and, it's not the tire. I can feel it....more of a thrusting or maybe like a "slipping".....but, it's not the xmission....it shifts and runs fine. The noise is definately rear axle area.

John

 

[Phluge]

95 Legacy Wagon with 140K miles.

Recently, from a stop, when I depress the accelerator, occasionally there is a thumping noise...one or two thumps, and then it ceases. Sounds like it is coming from the rear axle, but, not sure.

Other than that, car runs like new. Any ideas on what might be causing the strange noises??

Thanks, John

I can tell you from experience (see post: 90 LegacySW Front Drive Shaft) it sounds like it could be worn universal joints on your drive shaft, likely the rear one if the sound is coming from there, or it could be from the front one, or both.

Go back under and wiggle the drive shaft around to see if there is any play at all on either end -- even the tiniest play means it is going bad, and it will make sounds because of the tremendous torque. If you have dual (front and back shafts like mine) you may only need to replace one. Unlike on reasonably designed cars, I cannot simply replace the U-joints, but have to replace the shaft on mine-- I don't know what yours is like. If there is play, it will likely be near the rear transaxle or the front by the extension housing.

One of the signs mine were bad was thumping when starting out from dead stop. If you feel some play but they look OK you still have quite a bit of time ( I drove mine out of necessity for hundreds of high-speed miles until it is now barely hanging on and disabled). It doesn't sound to me like yours would be too bad yet. If that is it it will eventually start to rumble whenever you accelerate, and stop when you coast, and will squeek that sounds like a bad wheel bearing. But if it is wearing a little you should start looking for a replacement asap because it may take some hunting to find a replacement, I can tell you that.

Hope this helps.

Pflu

 

[John-USN]

Thank you.....great info, and I'm certain you are correct.

John

 

[Carl 1 Lucky Texan]

Thank you.....great info, and I'm certain you are correct.

John

I read somewhere that a common Ford U-joint can be welded on by a good driveshaft shop - maybe someone here or at www.ultimatesubaru.org will have details.

Carl

 

[Me]

Possibly a bad CV joint, have you checked the CV boots for tears or leakage etc?

Grant

 

[John-USN]

CV joints are probably shot. The car has 160K miles, and I am just using it for local trips. I'm not really into putting anymore money into the car....since the rust is getting worse. If my CV joints are bad (or going bad).....how much longer can I drive on them before it becomes unsafe?

Thanks, John