Surgeing and shaking

[wadessass308]

I have an '07. 5, 6. 7, 6sp, 34k mi. , bone stock. Since I bought the truck with 31k mi my service dept. has replaced 1 inj. , egr valve, computer and modules... My question is at 60-62mph with the cruise set I get an intermittent shaking or surgeing that lasts for a few seconds and stops. The only time I notice this is when I crest a hill and start down the other side. My service dept. has recreated this but can't figure it out. This is not a small vibration but a pretty harsh surgeing almost like running out of fuel. I was told my fuel pressure is ok. Any ideas or help would be great.

 

[HBarlow]

The surging you are experiencing is normal and nothing to worry about. My '08 does it on certain downgrades and so did my two previous Dodge Rams. I would not describe mine as "harsh" but it does surge enough to feel.

My guess is the cruise control-ECM interface is not quite sophisticated enough to smoothly manage the repeat transition from closed throttle (no fueling) to very slight fueling and back to closed throttle by the cruise control to preveent the slight surging we feel.