Our 2007 Grand Caravan has intermittent vibration which feels similar to driving over rumble bars. It usually occurs between 30-50 mph but sometimes at 70-80 mph as well. Have had the suspension checked and had outer tie rod end replaced. Also had sway bar bushings replaced and front end aligned. We then brought it to transmission shop and had a transmission diagnostic performed. They found no faults with the transmission and thought the engine needed a tune-up which we did with no success. At a recent oil change, we asked for them to test drive it and check again for any suspension problems. They did not notice any vibration during the test drive and found no problems with the suspension. Any thoughts or suggestions?
My prime suspect would be the transmission’s torque converter lock-up mechanism.
I suggest that you try a different trans shop.
Make sure that you do NOT go to a chain-run operation, such as AAMCO, Lee Myles, Cottman, or Mr. Transmission.
Thanks for your help.
Does it hurt anything to drive it this way as long as we can?
I’m not a transmission expert–by any means–but I don’t think that you are doing harm by driving it for the time being.
However, if the torque converter lock-up mechanism is indeed malfunctioning, you are using more gas than you would if it was working properly, so there is some cost involved with delaying the repair.