Does anyone make a device to tell when the Multi-Displacement System is on. I have a 07 hemi charger and a 08 ram 1500, but I don't really feel much of a difference driving so I don't when the mds system is being used. thanks

a cat back exhaust?

Basically with the exhaust slightly louder, you can hear it drop cylinders and the more cylinders it drops the worse it sounds.

Never heard of a little indicator light or anything along those lines...sorry

Here ya go...

http://www.lxforums.com/board/showthread.php?t=11575

Seems simply enough to do, thanks

The scangauge aftermarket trip computer and OBD-II monitoring readout will also show when MDS is engaged, plus what engine conditions are necessary:

http://www.scangauge.com/

if you are fiddling with MDS
you might also read this Australian post
and consider a capacitor/resistor filter
on the TPS that might keep MDS on longer
and prevent it dropping out with little throttle jerks

http://www.autospeed.com/cms/A_110187/article.html?popularArticle

I record the MDS on our shop computer and I can hardly ever feel it drop out and I know it works because I will see it on the recording when I get back in the shop. Ron