Kocking from rear passenger side

[tiger_e30]

Driving home today there was a knocking sound like a hammer in a dryer. Pulled over didn't see anything out of place, hit 20 and it came back with a vengeance. Anything to check besides driveshaft and guibo?

Sent from my SM-G920V using Tapatalk

[e30davie]

I'd be checking all the things that spin.

[glnr13]

also check your rear shock mount. when mine blew I could have described it as a hammer in a dryer.

is the sound rhythmic or kind of random?

[tiger_e30]

also check your rear shock mount. when mine blew I could have described it as a hammer in a dryer.

is the sound rhythmic or kind of random?

Very rhythmic

Sent from my SM-G920V using Tapatalk

[tiger_e30]

Sucks because I was going to be able to take it out on the BMW performance track next Saturday

Sent from my SM-G920V using Tapatalk

[tiger_e30]

Guibo looked good, wheel bearings are fine, can't find anything obviously bad. Took it out today and kept it under 20 and didn't hear anything. So my list right now is driveshaft, subframe bushings, and diff or CV axles.

Its very odd. Very violent sound and was constant bam bam bam. Anyone else ever have this happen?

Sent from my SM-G920V using Tapatalk

[tiger_e30]

Looks like this will turn into a case of while I'm in there.

I am going to

Pull the drive shaft and have it rebuilt.

Drop the subframe and replace subframe and trailing arm bushings.

Paint or powder coat everything I take off.

Diff rear is leaking so open it up, replace gasket. Replace diff mount.

Transmission mounts are shot so replace those and maybe do the clutch.

Diagnosis a transmission or engine oil leak. One of my transmission mounts is coated in black goop.

Anything else make sense while I'm in there?

Also any recommendations on best bushings or who to have rebuild driveshaft? Leaning towards Ireland engineering for the driveshaft.

[lukeADE335i]

My guess would be left rear CV joint.

I had a rhythmic clunking on the right rear of my car and it was the half shaft on that side.

[zaq123]

If it's right under your rear seat, I'd be checking rear subframe bushings

Sent from my VS985 4G using Tapatalk

[e30davie]

Looks like this will turn into a case of while I'm in there.
I am going to
Pull the drive shaft and have it rebuilt.
Drop the subframe and replace subframe and trailing arm bushings.
Paint or powder coat everything I take off.
Diff rear is leaking so open it up, replace gasket. Replace diff mount.
Transmission mounts are shot so replace those and maybe do the clutch.
Diagnosis a transmission or engine oil leak. One of my transmission mounts is coated in black goop.
Anything else make sense while I'm in there?
Also any recommendations on best bushings or who to have rebuild driveshaft? Leaning towards Ireland engineering for the driveshaft.

If you actually want to rebuild your driveshaft (which is replacing 2 CV joints and balancing it after). Google "driveshaft rebuild" and call the nearest shop. Dont send it across the country. These guys came up based on your Greenville SC location,

http://www.carolinadriveline.com/

What you have described there is days of work, and many hundreds if not thousands of dollars. If it were me i would find the actual problem and fix that rather than "fixing " everything and hoping to find the issue.

I do not see how a rythmic noise based on speed can be subframe bushes, or any bushes. you are looking for things that spin. The CV joint sounds like the most plausible, and if you take a wheel off you should be able to very quickly grab hold of the shaft and feel that a CV joint is stuffed. Compare it to the other side to double check.

Unlikely to be differential as it would be noisy all the time but if its not CV its worth checking that you havent lost any teeth on the gears. Unlikely to be driveshaft as you are not going fast enough for it to be vibration issue. Likely to be CV joint as they can drive "fine" at low speeds they can start to jump out of the CV cup thing when speeds start to increase a little.

If the noise is as nasty as you describe it it should not be difficult to locate. Depending how adventurous you are you can jack up the rear of the car, put it on jack stands and very carefully run it up to speed and try and hear the noise from outside. Get a competent friend to "drive" the car, so in the event that things go pear shape they can stop the car. do at your own risk of course, but being careful there should be no issues.

[tiger_e30]

If you actually want to rebuild your driveshaft (which is replacing 2 CV joints and balancing it after). Google "driveshaft rebuild" and call the nearest shop. Dont send it across the country. These guys came up based on your Greenville SC location,

http://www.carolinadriveline.com/

What you have described there is days of work, and many hundreds if not thousands of dollars. If it were me i would find the actual problem and fix that rather than "fixing " everything and hoping to find the issue.

I do not see how a rythmic noise based on speed can be subframe bushes, or any bushes. you are looking for things that spin. The CV joint sounds like the most plausible, and if you take a wheel off you should be able to very quickly grab hold of the shaft and feel that a CV joint is stuffed. Compare it to the other side to double check.

Unlikely to be differential as it would be noisy all the time but if its not CV its worth checking that you havent lost any teeth on the gears. Unlikely to be driveshaft as you are not going fast enough for it to be vibration issue. Likely to be CV joint as they can drive "fine" at low speeds they can start to jump out of the CV cup thing when speeds start to increase a little.

If the noise is as nasty as you describe it it should not be difficult to locate. Depending how adventurous you are you can jack up the rear of the car, put it on jack stands and very carefully run it up to speed and try and hear the noise from outside. Get a competent friend to "drive" the car, so in the event that things go pear shape they can stop the car. do at your own risk of course, but being careful there should be no issues.

Did as you suggested and if I grab the half shaft I can move it in and out and make a clunk. Drivers side seems to move less. I have no frame of reference should there be any axial play? Boots look good no tears

Sent from my SM-G920V using Tapatalk

[e30davie]

CV joints will move in and out as thats what happends when the suspension goes up and down. What i would be concerced with is laterla movement, which it might not do until it spins.

If you think its considerably worse than the other side you can remove the boots and slide them up the shaft and take a look at the CV joint itself. A noise such as your describing should yield alot of destruction.

You can wipe all the CV joint grease out for a better look, but you will need to replace the grease if its not the issues. CV joint grease is pretty cheap though.

If the CV turns out to be ok, but the CV boot back on and put a decent cable tie around it. Preferable to use a stainless steel cable tie. they are cheap as too. ($4 for a pack of 10 from my local hardware)

If the CV is stuffed, start removal of shaft.

[jeffnhiscars]

When you do your diff gasket also do the flange O rings. Cheap and easy once it's out. I've also had half shaft to output flange bolts back off and make a racket. Fortunately we stopped before it actually "threw a shaft" which could have been distatrous. Loctite is your friend

[zaq123]

When you do your diff gasket also do the flange O rings. Cheap and easy once it's out.

+1. Just do yourself a favor and mark all flanges and shims (behind them) and reinstall the same. Also if diff. pinion seal isn't leaking, leave it be. Other seals are easy to replace and don't affect R&P pattern if all parts reinstalled back as they were.

[tiger_e30]

Looks like everyone that said CV is right. Drivers side looks new but passenger side was either replaced with one that had 115k or was replaced at 115k which was 170,000 miles ago.

Saw some ones that must be Chinese for $50 which scared me; has anyone used GKN Loebro 33211226901 - CV Axle Assembly; Rear