QuestionQUESTION: I have a 1997 sl320 mercedes that vibrates when I accelerate..and now I hear a bumping sound from the back..towards the middle.I need a oil change and tune up..But would this cause the car to respond this way or is there more of a problem?
ANSWER: Nathan,
You may have a Universal joint going out. You can check yourself if you want to jack up the vehicle. The rear wheels need to be off the ground enough to rotate. Standard precautions apply. Jack stands etc.
With the vehicle in park front wheels chocked... have an assistant hold one wheel while you try to rock the other side.
There will be a little play in the gear mesh. With hands at 3 and 9 o'clock rock the tire as far as it will go in each direction. If you can hear a clank or lots of slop forward of the differential then you will need to have the propeller shaft joints checked. There may also be a carrier bearing that could be going bad if drive shaft is in two parts.
It is important that you have his knock checked and repaired immediately, because if the joint comes out and allows the propeller shaft to drop down, it could cause serious damage or even cause the vehicle to turn over at highway speed.
Good Luck and let us know what you fine.
Rob
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QUESTION: Thank you for the response. I believe you to be correct about the repair work needed..What would you suggest a job like this will cost to repair.? High and Low figure please.
AnswerNathan,
That's a loaded question. It depends on whether you do the work, an independent drive line shop does it or the dealer does. The dealer may be able to install the part, or they may send it out to a drive line specialist.
I once owned a new Ford conversion vehicle with extended body. It had a vibration from day one. The dealer had it back three or four time with not luck in correcting the problem after charging in excess of 400.00. The removed each length of shaft to have it checked it use three shafts.
I finally took the vehicle to a drive line specialist and for 100.00. He removed the total shaft including carrier bearing and spun the shaf as a unit. They found a bent flange on one of the pieces. After straightening and reinstall it was smooth as silk.
I recommend you get an estimate from an independent drive line shop.
Parts cost will depend on used, new, aftermarket, dealer. Least to most expensive.
Phone around and ask questions.
Locate your local mercedes club. Often there are guy/girls there who can suggest a competent individual to do the work.
You may be able to locate the replacement parts if you determine which one you need on ebay.
I often find parts for my 420SEL there.
Good Luck
Rob
