Hello,

I have my ram since only 1 week, then I discover it.
It's a '04 4,7L engine, 5 speed auto.

There is something strange, but I don't know it is normal or not.
When I'm driving between 45 and 55mi/h, the engine is between 1500rpm and 2000rpm.
and then I feel some smalls shocks, If I push on "tow/hall" to remove the overdrive, engine is about 3000rpm for same runing speed, then I don't feel the shocks.

Is somebody have the same ?

thank you.
GG

 

That is the overdrive on the 5 speed automatics, it actually cuts out 4 cylinders on the engine along with the one to one lock up converter drive.

 

Ok, thank's for answer ;-)

 

it doesnt cut our 4 cylinders on an 04 does it? isn thatmds which is on 06 and up

 

I don't believethe 4.7 has the MDS feature, only the Hemis.

My bet is if you're driving at 55mph, and you're feeling tiny bumps, it's the overdrive kicking in and out, as that's a close to OD lock-up speed, hence why it goes away in tow mode.

I'm willing to bet if you drive at 65mph, you won't feel it, out of tow mode.

 

I have an 04 4.7L with auto tranny. I've not experienced what you are describing.

 

My 4.7 has the MDS.

 

You're correct. I should have been clearer: HIS truck is an 04. MDS wasn't available in the 4.7 until 06.