Sg45

I put a set of ISS 3 piece forged wheels and new Michelin PS2's (295/35/19 on rear) on my SL550 in the summer.

I have noticed lately that when I accelerate hard while changing lanes (especially like entering the interstate, punching it and quickly moving over 2 or 3 lanes) that the rear end "waggles". That's the only way to describe it. Think about what the butt of a dog looks like when it's wagging it's tail. If I back off on the accelerator, it stops. I don't really get this when cornering hard on a two lane road, just straight line acceleration while changing lanes.

It is a bit scary. Almost feels like the wheels are ready to buckle (I don't think they are). I know a few others on here run these same ISS 3 piece wheels and I was just wondering across the board if anyone else has ever experienced this.

Thanks in advance!

Benz-O-Rama

Lots of discussion about the waggle with PS2's in the W211 AMG forum. Do a search in there....

lkirchner

I have the same size and make tires on my SL55 and the wiggle waggle is present on mine as well. It's the tires.

maxabo

I had them in front, and the car was ALL OVER THE STREET, in higher speeds!!!
Let go of the throttle in pure fear of my life, at 140-150 mph...

Later learned that if you want to put Michelin on to a Mercedes, make sure they have the "MO" label.
Because that stands for "Mercedes Only".
It all sounded like a fairy tail to me!

But I then replaced them with cheap Dunlop's, and she's now steady as a rock!

BTW, the Michelin tires also come in "PO" (Porsche Only).

Sg45

Interesting that you say that about MO because I had read that when I was buying Michelins. I specifically told the tire dealer this and he came back with the fact that they were available in PO and that the sidewall stiffness rating was exactly the same (as stiff as you could order them). So I ended up with PO instead of MO. Now I am wondering.....

Rook3300

Totally strange. I've got Michelin Pilot Sport A/S Plus on my SL500 and have never experienced wiggle at all on somewhat smooth surfaces at high speed. And I tend to drive the nuts off of my cars. (Granted, I'm down about 80 horsepower on the SL550...)

-ROOK

jmf003

Michelin website says
No mention of a "PO" grade but it's certainly possibly that people are using "PO" to mean one of the Porsche Nx grades.

As an aside, I've run the OEM Pirelli Rossos, Nitto NT555R2, and Conti Sport Contact3s on my SL. No wiggle with any of them.

cal1

you could try the new PS3. I didn't even know they existed when I was putting new T1Rs on my SL a few weeks ago. I had a set priced out just for fun. $400 each for the rear tires and $350 ea for the front. they better not have a waggle at that price.

Rook3300

Dayum. For that price you might as well pick up some racing semi-slicks and put them on for when it doesn't rain. Or move to the desert.

-ROOK

Sg45

So I checked my pressure and they were running about 2 lbs. low on the rears (31.5 and 32). I put them to 35 (i know the door label says 34) and it took a significant amount of waggle out (or at least I am telling myself it did).

I'll update tomorrow when I can go run it hard.

IngenereAMG

Mine has been wagging its tail since '03....... and putting a big grin on my face at the same time!

johno530

I noticed it on my CLK BS w/PS2's, but only on hard acceleration. I've found that it can inspire some interesting passenger commentary.

JBFMCAR

Yeah i have noticed this with my 19in PS2s as well and i have them set to factory pressures. But only notice under WOT in straight line. Weird more people have this i thought a wheel was loose at first!

Justin