I bought two replacement front rotors my my SLK32 AMG (same as SRT6) from Mercedes Benz. They came with directional internal cooling vanes, but they are both for the same side. The guy at the parts counter double-checked the parts #s. The system lists a left and a right brake rotor, but has the same part # for each.

I am really concerned with installing these because one rotor will have dramatically more cooling than the other.

Jessejamessrt6 ran into the same problem in a prior thread: https://www.crossfireforum.org/forum...otor-help.html

Rob at Needswings said the Powerslot rotors are the same way. (!)

Has anyone found rotors that come with a correct matched left and right pair on the cooling vanes, or non-directional (radial) cooling vanes?

 

My rear rotors came the same way... I even dredged through MB part numbers to see if they had an alternate. I just went ahead and mounted them. Not a single trouble since. --I'll grant you, the rear rotors I put on are the 330mm discs, but you get the idea.

 

I have seen three different sets and ALL have had the same directional vanes, no worries, we all have the same setup and none have experienced adverse issues that I am aware of....

 

I first encountered this rotor directional stuff years ago when I replaced the rotors on my 1990 GMC Suburban.
Being stupid, I put them on the wrong sides.
Hasn't been a problem.

 

I have some rears that I have not put on and they are definitely left and right handed and the box identifies them as such. That does not guarantee that I will not do a George.

 

Mine were of course labeled also, but who reads instructions anymore ?
Takes all the adventure out of it.

Question : if the vanes are turning the wrong way, does that then add additional heat during braking rather than dissipate it ?
( that's a joke - don't flame me )

 

Instructions? You mean it came with instructions?

 

Actually, I recall that they did.
The instructions said to clean off all the messy fingerprints with mineral spirits after installation and to put the calipers and wheels back in place before driving.
They were indispensable.

 

show me pics and I can help.
my rears (as vanes were straight) it did not matter. Front (vanes were directional) hence it was needed to go"clockwise" with the direction.

 

Mine fronts came the same way and I asked the same questions. I haven't had any problems, but have never ran it on the track. My rears were vertical so no issue.

 

Roadster has been fine for four years. No worries.

 

The plot thickens. These are my OEM front rotors. They are directional, and they are both left front rotors. One has more hot spots on it than the other, but I don't know if that was the right front rotor or not now.

Attachment 32127

These are the OEM rear rotors. They are not directional.

Attachment 32128

I found out from Rob at Needswings that Centric makes the Centric, Powerslot, and Stoptech rotors and that they are all directionally vaned left rotors.

If correctly vaned directional rotors or non-directional straight-vaned rotors are available, I don't know what they are. I am going to just install them and rock on

 

i hear ya. I went thru this 4 yrs ago. I never bothered with the coupe. Stock rotors are massive enough.

 

I don't have a set yet to check and see, but this is confusing because Stoptech says their Aerorotors are directionally vaned and show left and right part #'s. Is this just for the directionality of the drilled holes or slots? On the drilled rotors, drilled holes would be in between and in the direction of the vanes, no? And there is a left slant and a right slant.

 

If I recall correctly the holes and slots on mine were correct but both had the same direction vanes.

 

I just ordered a full set of centric slotted/drilled rotors for my car. They had 4 different part numbers so mid next week I will update with my findings. I am hoping they are slotted opposite, or at least straight, as my OCD would not allow the slots to go the wrong direction.

 

Read this StopTech page at TireRack it shows the differences in different models some left and right and some - not so much.

 

Same here, my R1 rotors are directional for the slot orientation only. The vanes are both for LH side. So after some heavy braking, I back up for about a km to allow even cooling of the rotors.... Just kidding!

 

180, I questioned a Tirerack support person through their online chat about the vane orientation and came away convinced that he had no idea what they sold.

Moparfreak69, let us know what you end up with. Thanks!

I am wondering now if the vanes are angled not primarily for airflow, but to support the friction surface evenly.

Once my brakes are fully bedded in I will try to get some side to side temperature measurements.

 

Here's a good article on slotted, drilled, directional vane rotors :
How to properly install plain, slotted, or drilled brake rotors