Another go at driveshaft balance

[Jonny B]

I have had a vibration in my 250 SL at about 55-60 mph pretty much since I have had the car (almost 14 years now). I finally decided to attack the issue. It also turned out that the drive shaft was not the correct one for the year/VIN. My mechanic had the rear part, a new unit, he sold me. I was able to get the front shaft from a friend who has various and sundry parts. I had the front shaft shortened to fit, and then the entire unit balanced and marked. A friend of mine and I put the new shaft in place a week and a half ago, but the vibrations are still there, in a different speed (on at about 65-70 and another smaller at ~40), but still noticeable, mostly in the rear view mirror. The only real trouble we had was getting the center guide mount in place.

There are two channels in the body that hold an adjustable nut that the center guide bolts to. One of the channels was messed up and it took us hours to finally get the guide bolted up. The guide bearing does not look fully centered, but do not really have a good reference on this. Could that be a part of the problem??

I also do need to get new tires, the old Cokers are pretty well past their time. Next up is a purchase of new white walls.

In reading through the threads, tires do play a part, and since I know these need to be replaced, the detective work will continue.

[Scottcorvette]

Many years ago my dad had a Corvette with a vibration like yours. He tried all sorts, driveshaft, rear end, transmission etc etc. In the end he tried the wheels and tires off another car and that cured it. Turns out when the tires were removed that the steel belting had worked loose inside the tire (or something along those lines, I can't remember completely). A new set of tires cured the vibration. If new ones are on the list it might be worth a try.

I would have thought though that if the driveshaft work has altered the vibration it has to be in that area.

[chumps]

I had the same problem 3 or 4 years ago. Not a teeth rattling vibration, but a very noticeable vibration at those speeds. It turned out that my  centering cross had gone bad (number 55 on the SLS diagram). I was able to secure a used one from one of the members of the club. I replaced it and the vibration was gone and no problem since. Chumps

[Cees Klumper]

I had this in a Triumph Spitfire and it was the driveshaft. I put the car on jackstands in the rear, started the engine, put it in gear, then held a chalk closer and closer to the spinning shaft, until it would touch. Is this case, the driveshaft wasn't centered where it connected to the transmission, causing the vibration. I fixed that, and the vibration was gone. All this to say that you could try something similar to see whether there is an imbalance/out of center condition with the (new) driveshaft someplace. And 2x on the wheels and tires.

[kampala]

Jonny,

Swap the wheels / tires with your 280 to rule-in or rule-out a wheel / tire issue.   As Scott mentioned, a slipped belt or such can cause this.   I have clearly had a slipped belt or other internal tire fault cause vibration twice in my driving life.    Worth  a shot since you have a second pagoda.   

[Shvegel]

If your car sits the tires can take a set.  My daily driver sits at the airport every other month and it takes around 20 miles to get the tires to round out again.  If it persists you might want to check the runout of the flange of the axle and the flange of the gearbox.

[cfm65@me.com]

Jonny,
Many years ago I bought a shot 230 SL. Loved, adored and drove it for a few years and then temporary fitted a 108 280SE engine and tranny. The 280 front end prop shaft had to be shortend and balanced. The car ran beautifly, smooth(remember, I live in Africa) for ten years before I could afford to overhaul and refit the 230SL engine, tranny and the original front end shaft.     We are talking 30 years ago.

If a prop shaft could be cut and balanced in Africa, your problem is elsewhere.

At the time, I also owned an early R107 350SL, and fitted a new set of Michelins, which turned this old girl into a super car.

Replace the tires, and we'll talk again.
Regards
Chris
Cape Town

[Jonny B]

Tires are the next thing on the agenda. Vibration or not, the tires on the car need to be replaced. Will post the results. Most likely going for Maxxis, as I want to get white walls. Just love the look.

[neelyrc]

Jon,
I'm with you! After many years on blacks I will go back to thin line WWs when I change my tires in a few days.  Do you have feedback from other owners on the Maxxis?

Coker Phoenix provide the most original look but I get nose bleed just thinking about the price.  I am leaning toward the Uniroyal Tiger Paw II which some other members here are using.

I hope the new tires are the answer to your vibration problem.

[Jonny B]

My good friend Martijn (who you met in Italy - tall fellow, with dark blue 250 SL) is running on the Maxxis, and they do run out just fine (especially after a 1600 km sample!!). I am not sure how long he has had them, but at least three years.

[mdsalemi]

Most likely going for Maxxis, as I want to get white walls. Just love the look.

I'd honestly never heard of Maxxis until today, but then again there's a lot of tires that I have not heard of if they aren't from the majors. The Maxxis website has about 5 models of passenger car tires listed, none appear to be in WSW. Which one were you planning on?

http://www.maxxis.com/tires/autolt/passenger

[66andBlue]

Mike,
I had asked him the same question; so here is the link:
http://shop.maxxis.com/c/ma-1-grand-touring-tire?action_type=switch_product&selected_cat_keys=12015.1071173.0.0.0&selected_product=cd51f203fb06a3d24cff1d34b27bf5f9&redirected_post=1
though, this may not be the size he'll select.

[Jonny B]

To finish out this topic (and will pick up with a new one). The driveshaft position was not correct and needed to be aligned with the differential. I had my mechanic take care of this, as I had played with it for too long. The alignment (adjusting the differential position) has been completed.

But the saga continues.... See the new post on the "while we're at it" aspect. - transmission stuff