High speed intermediate jerk

[jpsteyn]

I have a 2001 Grand Cherokee Limited, at about 65 000 miles it started while going to Chicago. When I am traveling faster than 50 mph. It feels like a small jerk every 500 to 700 feet. No warning lights comes on and the jerk frequency is very constant. This fault can go away for months and then suddenly reappear. Took the car in twice and the service center can find nothing wrong. Does anyone have any ideas ? Thanks.

[a_alyte]

It could be time to change your Transmission fluid, unless you've already done so recently.

I always try changing the little things 1st (& least expensive) & sometimes it works! Just my

[fredjacksonsan]

It might be going in and out of lockup. There was a post in the Dodge Truck forum where the rear speed sensor (on axle) was going bad. I'd have your mechanic check or replace those.

[fredjacksonsan]

And the fluid change wouldn't be a bad idea either.

[jpsteyn]

Thanks, I will try that.

[fredjacksonsan]

Good luck with it.

[89ltd]

does the rpm drop when it jerks?