300se vibration
 

Well i finished the cam instalition a few days ago and all is well now,no noise at all and engine runs great,next on the menu is vibration at 60 mph to 70 mph,I can't seem to get a handle on it yet,i have brand new michelin tires and balanced but cant get rid of the vibration,also replaced the engine and tranny mounts,i had the driveshaft removed several years ago and sent out for new u-joint and balancing and it was good for a long time but maybe it needs done again,i have had a lot of good help on this site with much appreciation,i need a little more advice now on this vibraton,thanks again for all the help received .

Sure none of the wheels are bent? They usually will just balance as close as they can get it, only really good shops will let you know your wheels are out of round.

Also steering dampener could be shot.

vibration
 

I think you are right on about bent wheel,i just had new michelin tire's installed and balanced yesterday,it seemed worse after they got done so i swapped lf and lr tires just to see if if something changed,lo and behold it was so much better,i do think rim is bent on lr now i think i will leave it on the back,thanks for your help,on to rear wheel bearing replacement,hope they are not too bad to do,have a great day.

Rocket, I have had a 20-year ongoing battle with wheel/tire vibration on my
'91 300SE. I could have new tires installed and balanced, and it would shake like crazy between 60-70. They would rebalance, find nothing wrong, and it would still shake. I could switch wheel locations, or just remount the same wheel on the same hub, and the vibes would sometimes stop!!
I am on my 3rd set of wheels in 20 years, but have never had a bent or wobbly wheel, just lots of mysterious vibration problems. I reached some conclusions over the years:
- these 126 cars are super-sensitive to wheel balance.
- these 126 cars put major abuse on the tires, from the suspension geometry and the weight. They can destroy the balance integrity of tires after only 10k miles.
- good quality tires are important, initially for good roundness, and longterm to retain their integrity. Get the best balance available on the best machine available, by the best technician available.
- Never rotate them L-R, the tires just can't take it.
- When mounting, never tighten them part-way, then put the car off the jack and finish tightening. Always cross-torque to spec with no weight on the tire.
- cross your fingers and hope for the best.

DG

84 500SEL I had a problem like this and found a bent left front hub. Found it by luck when I bought a parts car that had all new rotors, calipers, bearings, etc. I wanted the rotors and bearings so I just removed them and changed hubs and all. Vibration gone. The other thing I found helps, wheel balancers have a normal mode where anything under 1/2 ounce will round off to 0. They can be set to NOT round off. I balance mine to less than 1/4 oz and it is smoooooth. It may be hard to find someone to do this as it takes more time.

Paul