Sorry but another Cruise Control ?

2005 Ram 1500 4.7 SLT 4x4 Quad Cab 150,000 miles

Was using the cruise the other day and set it about 65 and held fine. Hit decel ONCE and it dropped to almost 60. Hit accel once and I swear it went up to like 64. Any idea what might be causing this? I’ve never had a vehicle that didn’t do at or about 1 mph change per button push.

Digital (1 MPH setpoint changes) are pretty standard on current vehicles, but on older ones, the change in setpoint was often a function of how long you hold the button down OR simply a snapshot of the actual speed once it's decelerated or accelerated slightly based on which button you pushed. Also, with a 15 year old vehicle, there's the possibility that the speed feedback signal into the CPU may be a little flakey or intermittent, causing the slightly inaccurate responses to your changes.

Another variable is whether you were setting the speed on the level, or going up-hill/down-hill. The truck will change speeds differently in response to your accel/decel button depending on the gravity assisted inertia. That is....it may decel faster, accel slower on the uphill, and vice-versa on the down hill. Try it on level ground, and I bet you get more consistent results.

Someone who knows the exact method on your 2005 will need to chime in. I just tossed out some generic possibilities.

I have a 2005 and it accelerates / decelerates in 1 mph increments.

Thanks for the responses. I know it’s older and it may just be worn out. Not a huge deal but do like using the cruise to keep from getting a ticket.