Noise coming from the driver rear that sounds like someone is under the car hitting something metal with a hammer. This happened about 400 miles ago, after we jacked it up by the differential and looked at everything. We could not find anything wrong. The axels were rebooted about 1000 miles ago before the original boots ripped. The noise went away after jacking it up but its BACK. We jacked it up again yesterday and still could not find anything. This time we had both wheels of and put it in D and reved it up ---- no noise. Put the wheels on and drove it --- no noise. Any suggestions would be appreciated as we are stumped.

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Gary
OBK #37

Clunking like you describe with the intermittency factor is usually a cv joint. When you rebooted you did replace the lubricant in sufficent quantities? If you used a grease perhaps an injection of heavy oil could be added to the boot.

Sounds like a cv joint getting warm after some miles without enough lubricant. Of course I imagine it could be something else. Your description just favored a cv joint to me. If the noise is repedative at the same duration or rythmitic in nature.

Random noise on bumps etc of course disqualifies the cv joint.

Try to get a syringe and inject some CV lub into the joint. I bet you that the axle leaked it all out.

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-Typos courtesy of my mobile phone.

Have you recently used the parking brake?

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Gone to the dark side

- Jeff

The oil that came out of the CV joints measured the same on both sides i.e. the outside CV vs the inside. I used the grease that came with the boots. Yes I use the parking brake religiously and they work perfectly and the shoes have plenty of thickness left. We had the caliper off and the brake drum off yesterday. Another friend suggested that it could be the sub frame mounts. I am going to look at those today shortly.

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Gary
OBK #37

Does this car have the plastic rear sway bar links? If so, replace them.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Why I asked if you used grease. When changing out old cv joints I have seen examples where the grease had basically been displaced totally from the ball area. Because of this I felt the cv joints had failed.

I always liked the mercedes oil approach as it will always flow back in. Their cv joints although being on the back of a car favor them. Seem to last a very long time if lubricated constantly.

If what you heard was a constant rhythmic clunking I doubt it is mount bushings as I think you would only hear from them on bumps etc if they were shot. Like someone already mentioned. Removal of the small boot clamp and injecting some heavy oil should do no harm. If the joint is pretty dry the longer you wait the more damage.

I would absolutely check the plastic swaybar links. They make quite the clunk when they wear out.

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Serenity-86' 300SDL 482,000 miles (on a "14" head!)

I pulled the swaybar rear links off the car and I have not heard the noise again. The links are complete but the rubber dust covers are long gone, the balls swivel and are not loose. I will continue to drive around with out them on and see if the noise comes back. I had a 400 mile interval that the noise did not happen. I may just jack it up, put it on jack stands, remove the inner clamp on the boot and inject some 80 or 90 weight gear oil in there and reclamp it. JedClampet! It emptied out approx 90 cc's each boot when I rebooted the CV's.

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Gary
OBK #37

You use the parking brake on sundays only? Religiously?

Kidding aside, a loose parking brake cable will sometimes jingle or clatter. If pushing the pedal down a click silences it, you've got a loose cable.

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Gone to the dark side

- Jeff

Yesterday we pulled down the subframe and looked and felt the bushings and they looked like new. Then we pulled off the larger clamp on the CV boots and injected some 70/90 differential oil into the can 2 1/2 oz per boot. We also replaced the swaybar links. Hopefully this will clear up the clunk sound.

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Gary
OBK #37

Rhythmic thumping on my 85TD went away with injection of oil into the CV boots.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

replace them with what? on my 190e, i put metal end links which were off a 300te wagon. it helps the rear sway bar 'load' faster than the plastic and doesn't break like hte plastic ones do. is there is a similar upgrade for 123's that i don't know of?

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When a cv joint initially starts to clunk intermittently it will usually be after driving awhile. That is in a way the cv joints trademark. They usually have to warm up a little with inadaquate lubricant to start. Sometimes over a hundred miles. Nothing is written in stone though. Some cv joints may still have partial lubrication. The amount in there is not constant from car to car. Nor the state of the existing lubricant.

One really good attraction to the design by me was the use of oil instead of grease from the factory. Some greases seem to displace themselves from the needed areas. Oil does not have that option.

The important thing then is to get the additional lubricant in before they really damage themselves totally. One should never deffer adding the oil as soon as possible. At the very first symptom is best. Wait and see can be costly.

Once the clunking becomes constant it is usually too late except to replace the axle. These joints last a very long time on the 123s in my opinion if lubricated properly.

You may be able to almost double their lifespan by interchanging them from side to side as well. For example if you aquire a high milage example and assume the original axles are still on the car. The effort to switch them each to the otherside may be worth it if there are no problems at all with them currently.

The real problem is that high quality new oem replacement axles are really expensive so pre emptive strikes should be worthwhile. You get to use the unworn areas of the cv joints by rotating the axles.. Again a usless gesture if the clunking is constant already. If I for example lost a cv joint. I would not want to use the cheap chinese axle at this point. There have been problems with a percentage of them. The rebuilder that most have been happy with is discontinuing rebuilding them I understand as well.

I have not priced an original new replacement but guess 400.00 plus per axle. So my plan of attack if I lose a cv joint is to go to a salvage yard. Find an axle on the other side than the side I need with a good or intact boot at least. Relube it and install it. Most cars are not scrapped because the axle is bad or noisy. Yet you know the unknown axle has unknown miles. By installing it on the other side it will just be starting to really use unworn areas of the cv joints. so another 200k plus miles may be possible. Cost might be 50.00 for the used axle.

Ha!!..... I just went through this exact same scenario a few days ago. When I heard the clunking I would just move the drivers axle in and out a few times and then it would go away for a while.

After pulling the drivers outer boot, pulling the axle shaft towards the wheel and forcing a tube of CVJ grease into the joint... The clunking is gone.

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AJ

1985 300D (SOLD)