Hello All,

Car is an 83 300SD 180K.

While changing the left rear wheel bearing I moved the outer CV joint through its range of motion and felt a large detent. I would think the inner CV joint is the same way. I do not hear any noise or feel any vibration while driving.

The CV boots are starting to crack and I'm wondering if I should go through the trouble of changing the boots/regrease the joints or wait for the boots to fail and install new/quality rebuilt axles.

I know there is no precise answer, but is the axle fairly close to the end of its life, or have others felt this in their axles and after rebooting gotten another 100K out of them? I drive about 30K a year and plan on keeping the car.

Thanks

Richard

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Richard
'83 300SD 180k
'87 300SDL "200k"
Central Ohio

I had the same issue with my 84 300sd. I would recommend that you just keep using these until they fail completely. Going through the process of regreasing and replacing the boots is a tedius task and if they fail again (its doubtful you will get another 100k) then you will be out even more money. just my input..

It sure was a tedious task the way I did it. (50 ton press involved!) But if your boots really haven't let any dirt in, you should do a search on Youtube where a guy had an amazing method with a funnel!

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Thanx,
Alberta Luthier
1983 300CD ('Stinky')155k miles, 2.47 diff, EGR removed, AAZ injectors with 265 nozzles from Sean,and vogtland lowering springs.
1984 300SD ('Old Blue')150k Klicks from Japan originally, came with rear head rests, no sunroof and never had an EGR

I tried the Funnel bit, if you try it, make sure you use flex boots or it will not work.
Kevin

If the boots are cracked but not yet leaking, you can apply some of the black ATV silicone sealant to all the cracks. Let dry and you are good to go.

If the boots are just a bit cracked, I'd leave them alone. Lots of members have reported driving on cracked boots for years. If the cracks bother you, apply the ATV and let dry.

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84 300DT Puke Yellow. Totalled after 438,000
84 300DT Orient Red. 169,000 (actual mileage may vary)
2002 Explorer EB (wife's)

I passed on that Funnel method only to find out that it works with Flexx boots an other boots may be too stiff.

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84 300D, 82 Volvo 244Gl Diesel

Sounds like you may just plaster the present boots with silicone. If you get the urge to change the boots out instead. Just by re installing the axels on the opposite sides you have a new wear surface to wear down.
In fact it is thought the axles will last as long as they did already or longer by doing this. Always sounded reasonable to me if you think about it. Once real damage has occured in a cv joint this approach should not be used. Otherwise I would go for it.

Thanks everyone for the input. I think I will just cover the boots with some stuff, either the RTV or I think I remember someone spraying the boots with undercoating, and wait for the boots to die. Then replace the axles.

I don't seem to have as much luck with parts lasting as long as others, or maybe I'm too picky. On the 83 300SD the rear wheel bearing went out at 175k, AC compressor at 155k, and the drive shaft got replaced around 150k.

On the 87 300SDL I just picked within the past 6 months with at least 200k (the odometer was broken for 2-3 years from what I can tell) I've replaced the heater core, CV boots look like crap, replaced the Klima relay and still have more work to do on the AC, ABS pump needs replaced because of black goo, and the drive shaft is making annoying vibrations.

I'm not complaining because I don't really expect CV joints or a drive shaft u-joint to last past much past 200k (actually, I think that is great compared to most cars) but I would like to brag and say "mine is still going strong" just once

Richard

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Richard
'83 300SD 180k
'87 300SDL "200k"
Central Ohio

My right rear axle was noisy. The local indy injected lubricant and solved the problem. I don't think the job was very difficult but I did not watch them do it. I'm under the impression they may have loosened one end of the boot to put in the grease.

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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

The cheap way out is to get a used one. Its a 4hour swapout for a first timer.

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Never forget the original type cv joints are really high quality in my opinion. Reversal of axels has a much better index of satisfaction and less failure risk than buying reconditioned or inferior quality aftermarket new axels. In only perhaps my opinion based on other brands of cars. New original quality mercedes axels are so expensive they give pause for thought. This success hinges on no noise problems at the time of swap and verification the internal lubricant is good and of enough quantity.

In otherwords replacement may not always be the best approach in my opinion. If you apply silicone to the rear boots it will kind of support the material around the cracks and stop leakage if a crack completes it's way through the boot. Oil would dissolve most undercoating if applied plus the undercoating would have much less chance to endure the constant flexing of the boot.
Laquer thinner would make a good pre cleaner for the silicone. It dries off fast and seems to leave no actual harmful residue. Actually I have always liked it for a quick cleaning solvent because of the fast drying and ability to dissolve and float contaminates away. You just clean until the liquid on the cloth is clean. Use white cloths for best results. Use a cheap brush for application.
The surface will be bone dry a few minutes later. I buy the stuff by the five gallon can in a lower quality usually called gun wash. All auto body supply places stock it. Price has trended upwards like most things but still reasonable. Many many applications. A lot cheaper than using any form of spray can you can buy over time and again far better in most applications.

Good point about the oil possibly dissolving the undercoating and thank you for the cleaning suggestion. Time for the laquer thinner and RTV!!

Now, about reversal of the axles. How does one "verify" the condition and quantity of the lube in the joint?

Richard

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Richard
'83 300SD 180k
'87 300SDL "200k"
Central Ohio

If the boots are not torn, the lubricant should still be good since it is not subjected to the outside dirt, water, etc.

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RRGrassi


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