My dad has a chevy suburban that has an MDS system in it and he said if he turns on and sets his cruise control it will not kick on. Does anyone know if this is true for the Dodge's as well?

Thanks

 

Captain,

If appropriate the MDS should still work while cruise control is on assuming the power of 4 cylinders can accomplish maintaining the desired speed on relatively flat terrain without the need for shifting to occur. From owners manual below.

MULTI DISPLACEMENT SYSTEM (MDS) - 5.7L
Engine Only

This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.

 

I would think it'd be a complete waste to have a cylinder de-activation system and have it NOT operate in cruise control. You use cruise control on the highway while cruising AT THE EXACT TIME you'd benefit the most from cylinder shut down when you don't need all 8 to maintain speed on the interstate.
I have a hard time believing GM would do that...